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Feeding and Powering the World 2017
Oxford, Mississippi
June 19 & 20, 2017
Feeding and Powering the World 2017: Building the Knowledge Base
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In this collaborative research program funded by the National Science Foundation under grant number OIA-1539035, the expertise of more than six research groups has been combined to address critical, multi-disciplinary challenges in the Water-Energy-Food Nexus: the production of hydrogen, the reduction of carbon dioxide to useable fuel, and the reduction of nitrogen to synthetic fertilizer. Currently, nearly all hydrogen is synthesized from non-renewable carbon sources and carbon dioxide is treated as an abundant waste. Additionally, the Haber-Bosch process for using this hydrogen to reduce nitrogen is energy intensive, which demands further fossil fuel consumption. This program has a long-range approach (1) to establish technologies to extract hydrogen efficiently and economically from water using sunlight; (2) to establish technologies that use electron/proton pairs to directly reduce carbon dioxide to usable fuels at voltages obtainable by DSC devices; (3) to establish technologies that will fix nitrogen at lower temperatures and pressures, and ultimately (4) to link these technologies with high-voltage solar cells to use electron/proton pairs derived from catalytic water splitting to directly produce molecular hydrogen fuel, reduce carbon dioxide to produce fuels and nitrogen in one cell to produce ammonia - a key component of synthetic fertilizer.
State-of-the-art photoelectrochemical (PEC) cells rely on water soluble, high-toxicity lead-based materials to produce hydrogen from water and operate at 12.3% efficiency with a tandem double-layer solar cell. Goals here include: (1) the design and demonstration of practical, low-toxicity organic materials as single-layer solar cell components in PEC devices, and (2) the demonstration of a hydrogen production efficiency nearing 15% - a commercially viable number with low-cost materials. These materials would be a dramatic step forward in the PEC field for hydrogen production. Additionally, viable carbon reduction catalysts and a low pressure, reduced-temperature process for nitrogen reduction are highly desirable technologies. The iterative evaluation of carbon dioxide and molecular nitrogen reduction catalysts is proposed through a research loop including: (1) synthesis of potential catalysts, (2) photophysical analysis, (3) electrochemical analysis, and (4) computational analysis to suggest future catalyst targets. This process will allow for a rapid evaluation of catalyst designs for high reduction activity. Ideally, these processes will be linked to facilitate the formal reduction of carbon dioxide and nitrogen with water and sunlight as inputs.
The reduction of carbon dioxide and molecular nitrogen with hydrogen are critical processes to fuel and food production. Dramatic improvements in PEC hydrogen-producing cell efficiencies with viable, non-toxic materials, as well as the low-pressure, low-temperature reduction of molecular nitrogen are desirable for practical, sustainable fertilizer synthesis. The importance of efforts improving the route to synthetic fertilizer should not be understated. As such, a key aspect to sustainable funding is public awareness and involvement of the community through outreach. The critical goal of heightening public awareness through science cafes and public service announcements directed at the K-12, community college, and university levels as well as at the general public is also a key priority.
The goal of this conference is to bring together in one location all of the faculty, students, and all other participants of this program to report achievements, develop new relationships and collaborations, teach each other new skills, and make plans for the upcoming year.
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Jackson Avenue Center Ballroom, 1111 West Jackson Avenue, Oxford, MS 38655
Meeting at a Glance:
Monday June 19
9:30 am - 10:00 am : Pick up Name Tags and Programs and Hang up Posters
10:00am : Welcome by Prof. Gregory S. Tschumper, Chair of Chemistry & Biochemistry
10:05 am - 12:25 pm : Presentations and Open Discussions
12:25 pm - 2:00 pm : Lunch and Workshop on Finding a Good Work/Life Balance
2:00 pm - 5:35 pm : Presentations and Open Discussions
5:35 pm – 5:45 pm : Group Photograph
5:45 pm – 7:00 pm : Poster Competition
7:00 pm - 11:00 pm : Dinner, Collaboration, and Networking on Your Own
Tuesday June 20
8:00 am - 10:00 am : Senior Personnel Meeting
8:00 am - 10:00 am : Breakfast on Your Own
10:00 am - 12:15 pm : Presentations and Open Discussions
12:15 pm - 2:00 pm : Lunch and Workshop on Landing That First Job
2:00 pm - 4:00 pm : Presentations and Open Discussions
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Detailed Meeting Agenda:
Monday June 19 Jackson Avenue Center Ballroom 10:00 am - 12:25 pm : Presentations and Open Discussions 10:00 am Welcome by Prof. Gregory S. Tschumper, Chair of Chemistry & Biochemistry 10:05 am Nathan Hammer “A Short Introduction to Laser-Based Molecular Spectroscopy” with Louis McNamara providing an excited state lifetime demonstration 10:35 am Shane Autry “Spectroscopic Characterization of the Physical and
Photophysical Properties of Newly Developed Pincer Complexes”
10:50 am April Steen “Photophysical Characterization of Bipyridyl Hybrid
Oligomers: Examining Mixed Furan-Thiophene Systems Using
Spectroscopy and DFT Methods”
11:05 am Open Discussion / Collaboration Time
11:15 am Eric Van Dornshuld “A Primer on Computational Chemistry” 12:00 pm Robert Lamb “New Insights into the Mechanism of the HER Catalyzed by (py-NHC-p-CF3Ph)W(CO)4” 12:15 pm Open Discussion / Collaboration Time
12:25 - 2:00 pm Lunch and Workshop “Everything you wanted to know but were
afraid to ask” coordinated by Elizabeth Papish
2:00 pm - 5:35 pm : Presentations and Open Discussions
2:00 pm Georgette M. Lang “Oxidation of a CCC-NHC Pt(II) Complex via O-atom
Transfer Reactions”
2:15 pm Jason A. Denny, “Synthesis and Characterization of Rhodium CCC-NHC
Pincer Complexes”
2:30 pm Open Discussion / Collaboration Time
2:40 pm Jared Delcamp “Desirable Material Properties for DSCs and How to
Fabricate a DSC Device”
3:10 pm Hammad Cheema “Photon Management in Sequential Series Tandem
Dye-Sensitized Solar Cells (SST-DSCs)”
3:25 pm Nalaka P. Liyanage “Electrocatalytic Reduction of Dinitrogen into NH3”
3:40 pm Open Discussion / Collaboration Time / Break
4:00 pm Shanlin Pan “Basics of Electrochemistry and Operation Principle of
Scanning Electrochemical Microscope for Searching Electrocatalysts”
4:40 pm Pravin S. Shinde “Improved PEC activity for H2 evolution reaction from
surface-passivated Cu2O photocathode using bifunctional MoSx-catalyst”
4:55 pm Yiliyasi Wusimanjiang “Plasmonic metal Au NP coated scanning probe
nanoelectrode for spectroelectrochemistry and imaging”
5:10 pm Open Discussion / Collaboration Time
5:20 pm Katie Echols “An Overview of Program Outreach Activities”
5:35 pm – 5:45 pm : Group Photograph
5:45 pm – 7:00 pm : Poster Competition
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Tuesday June 20
8:00 am - 10:00 am : Senior Personnel Meeting
8:00 am - 10:00 am : Breakfast on Your Own
10:00 am - 12:15 pm : Presentations and Open Discussions
10:00 am Russell Schmehl “Tracking Electrons and Holes in Solar Photochemistry
Using Laser Flash Photolysis and Spectroelectrochemistry”
10:30 am Stephen L. Guertin “Investigation into the Mechanism of Proton
Reduction Catalysis by Chromophore-Catalyst [W(PyNHCPhCF3)(CO)4]”
10:45 am Open Discussion / Collaboration Time
11:00 am Jonah Jurss “Renewable Energy Conversion in the Jurss Group”
11:20 am Lizhu Chen “Durable and Highly Reactive Iron-Oxo Catalysts for
Hydrocarbon C-H Bond Functionalization”
11:35 am James Donahue “Coordination Chemistry and Small Molecule Activations
Motivated by Metalloenzymes”
12:00 pm Open Discussion / Collaboration Time
12:15 - 2:00 pm Lunch and Workshop “How to Land that First Job” coordinated by
Keith Hollis
2:00 pm - 4:00 pm : Presentations and Open Discussions
2:00 pm Elizabeth Papish “Tools for Kinetics and Mechanistic Studies”
2:45 pm Chance M. Boudreaux “Ruthenium CNC-Pincer Complexes Bridging the
Gap for Artificial Photosynthesis”
3:00 pm Fengrui Qu “Dual activated ruthenium complexes as anticancer
prodrugs”
3:15 pm Open Discussion / Collaboration Time
4:00 pm Farewell
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Senior Faculty at the 2015 SouthEastern Regional Meeting of the American Chemical
Society (SERMACS 2015) in Memphis, Tennessee in November, 2015.
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Dr. Jared Delcamp
University of Mississippi
Senior Personnel
"Desirable Material Properties for DSCs and How to Fabricate a DSC Device"
This talk will cover the ideal properties looked for in DSC materials and how to fabricate DSC
devices. The materials discussion will focus on the ideal energy levels of each component: the
semiconductor, the dye, and the redox shuttle for high efficiency devices, high voltage
devices and tandem devices. A pictorial demonstration will be provided as a tutorial for how
to construct a single junction and a sequential series tandem DSC system. Actual cells made
in the Delcamp labs will be provided for the audience to examine. The techniques and
instrument used to characterize these devices will be explained with example data discussed.
Questions and discussions are strongly encouraged during this tutorial session.
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Dr. Nathan Hammer
University of Mississippi
Senior Personnel
"A Short Introduction to Laser-Based Molecular Spectroscopy"
This lecture will introduce everyone to the fundamentals of laser-based molecular
spectroscopic techniques. In particular, the different energetic degrees of freedom,
interactions of matter with the electromagnetic spectrum, and spectroscopic tools employed
in this research program will be discussed. Representative spectroscopic data important to
this program will be used as illustrative examples.
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Dr. Keith Hollis
Mississippi State University
Senior Personnel
"How to Land that First Job"
This workshop will detail the process, products, details and perspectives needed to be a
highly competitive candidate for a job. Descriptions of priorities to get invited for the
interview, keys to standing out in the interview, and landing the job will be discussed. Some
emphasis will be given to soft skills development that drives much of the formalized hiring
process of major corporations today.
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Dr. Shanlin Pan
University of Alabama
Senior Personnel
"Basics of Electrochemistry and Operation Principle of Scanning Electrochemical Microscope
for Searching Electrocatalysts"
Several fundamental aspects of electrochemistry and the application of electrochemical
methods to chemical/engineering problems will be briefly described. Although it is
impossible for a rigorous consideration of voltammetric and coulometric methods in such
short source, I will describe the effect of mass transfer and kinetics on features of cyclic
voltammetry of a redox reaction. Electrode size and shape effects on voltammetry will be
discussed toward the understanding of microelectrode electrochemistry for applications in
scanning electrochemical microscopy (SECM), which can be used for searching
electrocatalysts for solar fuels and fuel cells.
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Dr. Russ Schmehl
Tulane University
Senior Personnel
"Tracking Electrons and Holes in Solar Photochemistry Using Laser Flash Photolysis and
Spectroelectrochemistry"
This lecture will give an overview of the research goal of and techniques employed by the
Schmehl Research Group at Tulane University.
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Dr. Charles Edwin Webster
Mississippi State University
Senior Personnel
"Computational Chemistry: A Primer"
Postdoctoral research associate Eric Van Dornshuld, under the direction of Prof. Webster,
will present a primer on computational chemistry and how it relates to this project.
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Dr. James Donahue
Tulane University
Seed Grant Recipient, Year 2
"Coordination Chemistry and Small Molecule Activations Motivated by Metalloenzymes"
This lecture will give an overview of the research goal of and techniques employed by the
Donahue Research Group at Tulane University.
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Dr. Jonah Jurss
University of Mississippi
Seed Grant Recipient, Years 1 & 2
"Renewable Energy Conversion in the Jurss Group"
This lecture will give an overview of the research goal of and techniques employed by the
Jurss Research Group at the University of Mississippi.
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Dr. Elizabeth Papish
University of Alabama
Seed Grant Recipient, Years 1 & 2
"Tools for Kinetics and Mechanistic Studies" This talk will discuss tools for kinetics and mechanistic studies. These include ReactIR,
stopped flow, a small UV-Vis instrument in the glovebox, O2 sensors for water oxidation, Parr
vessels for hydrogenation, and others. We will address how gathering kinetic data can help
scientists understand mechanisms. This is an open call to have more people use our
instruments. Some of our instruments are used heavily (e.g. ReactIR) and data from our
recent papers will be shown. Some tools, such as stopped flow, have been used more rarely,
but they are very powerful and participants are encouraged to utilize them more.
“Everything you wanted to know but were afraid to ask”
This workshop will cover how to do an effective job search, how to determine the correct job
for you after grad school (e.g. academia vs. industry vs. non-traditional careers), and
managing a work-life balance and having a family while pursuing your career goals. This
workshop will also cover basically any other concern or question students may have.
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Spectroscopic Characterization of the Physical and Photophysical Properties of Newly Developed
Platinum Pincer Complexes
Shane A. Autry,1 Min Zhang,2 Vivek Dixit,2 T. Keith Hollis,2 Charles Edwin Webster,2 and Nathan I. Hammer1
1Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
2Department of Chemistry, Mississippi State University, Starkville, MS 39762
In recent years the popularity of studying N-heterocyclic carbene pincer complexes for their
emissive properties has gradually risen. This is attributed to their accessible excited states
using low energy excitation. Here, we employ various spectroscopic methods in order to
characterize the physical and photophysical properties of newly-synthesized platinum pincer
complexes designed for emissive material applications. The photophysical efficiencies of
these new complexes are also investigated with the use of UV/visible absorbance, emission,
and quantum yield studies. We also analyze the physical stability of the platinum pincers via
long term exposure to UV/visible light.
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Ruthenium CNC-Pincer Complexes Bridging the Gap for Artificial Photosynthesis
Chance M. Boudreaux,1 Nalaka P. Liyanage,2 Hunter Shirly,2 Sopheavy Siek,1 Deidra L. Gerlach,1 Fengrui Qu,1 Jared H. Delcamp,2
and Elizabeth T. Papish1
1Department of Chemistry, University of Alabama, Tuscaloosa, AL 35401
2Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
Efficient catalyst design for the industrial scale conversion of CO2 to CO is a necessary step in
the pathway of converting our major energy feedstock, petroleum products, into a renewable
cycle. The established Fischer-Tropsch process can then be used to generate diesel fuel from
CO. However, the synthesis of only CO from CO2 is challenging due to a large number of
reduction products with relatively close energy potentials. Nevertheless, the ruthenium
complex, [(CNCOMeMe)Ru(CH3CN)2Cl)]OTf, described herein is the first ruthenium complex to
selectively reduce CO2 to CO. The pincer ligand, CNCOMe, is composed of NHC rings providing
carbon donors and a 4-methoxy-pyridine derived ring as the nitrogen donor. The methoxy
group is critical for the photocatalytic CO2 reduction; only 4 turnovers of CO production is
seen without the substituent. The catalyst undergoes >250 turnover cycles and is active for
more than 40 h. The catalytic data collected from these complex and close derivatives
illustrates trends in catalytic activity and represents progress towards producing more
industrially useful catalysts.
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Photon Management in Sequential Series Tandem Dye-Sensitized Solar Cells (SST-DSCs)
Hammad Cheema, Roberta R. Rodrigues, and Jared H. Delcamp
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
Sequential series tandem dye-sensitized solar cells (SST-DSCs), which are mechanically
stacked single illuminated area DSC devices wired in series, are reported to have the highest
photovoltages obtained from a single illuminated area DSC. The use of multiple photoactive
films under one area within the SST-DSC framework is made possible by fine tuning the
thickness of TiO2 in each device and judicious dye selection to allow for excellent light
distribution among the films, termed as “photon management”. Photovoltages (Voc) ranging
from 1.9-4.7 V are observed for SST-DSCs fabricated from 2-5 stacked subcells constructed
with metal-free organic dyes and cobalt redox shuttles. In SST-DSCs photon management
approach allows for incorporation of materials designed to use the maximal potential energy
of photons in each region of the solar spectrum. Importantly, SST-DSCs were observed to
maintain high Voc under low-light conditions, rendering these systems very attractive for
indoor applications. Additionally, a SST-DSC was found to have a solar-to-fuel conversion
efficiency of 2% (2.7% including H2 production) for the reduction of CO2 to CO with IrO2 and
Au2O3 electrocatalysts, without an external bias.
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Durable and Highly Reactive Iron-Oxo Catalysts for Hydrocarbon C-H Bond Functionalization
Lizhu Chen, Xiao-Jun Su, and Jonah W. Jurss
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
Petroleum and natural gas are important sources of inexpensive hydrocarbons for the chemical and pharmaceutical industries. The selective conversion of C-H bonds into new functional groups under mild conditions is therefore of considerable interest. In this context, high-valent non-heme iron-oxo catalysts have been developed as potent oxidants for the functionalization of unactivated C-H bonds. Previous studies have advanced our mechanistic understanding of these versatile intermediates, provided insight into the role of spin state on reactivity, and made commendable strides in product selectivity and substrate scope. However, a significant limitation of synthetic non-heme iron-oxo catalysts is poor stability and low turnover numbers under the harsh oxidizing conditions required of C-H bond oxidation. Polydentate ligands used in previous systems typically utilize oxidatively-weak, aliphatic linking groups and alkyl amine donors that are susceptible to catalyst decomposition. In order to improve catalyst stability while preserving high reactivity, we have developed new catalysts employing oxidatively-rugged tetradentate ligands comprised of robust aromatic building blocks, which provide cis-labile coordination sites at iron. Reactivity studies show that these catalysts are indeed durable and capable of oxidizing strong hydrocarbon C-H bonds, including those of benzene (C-H bond dissociation energy = 112 kcal/mol), with high conversion percentages.
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Synthesis and Characterization of Rhodium CCC-NHC Pincer Complexes
Jason A. Denny, Robert W. Lamb, Charles Edwin Webster, and T. Keith Hollis
Department of Chemistry, Mississippi State University, Starkville, MS 39762
A series of rhodium CCC-NHC pincer complexes was synthesized and characterized. The
series features the stepwise reduction and isolation of Rh(III), Rh(II), and Rh(I) carbonyl
complexes. The structures were determined by X-ray diffraction analysis. DFT computations
aided in the calculation of reduction pathways and possible intermediates. Further reactivity
studies were performed to probe the potential applications for these novel CCC-NHC
rhodium pincer complexes.
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Investigation into the Mechanism of Proton Reduction Catalysis by Chromophore-Catalyst
[W(PyNHCPhCF3)(CO)4]
Stephen L. Guertin,1 Aron J. Huckaba,2 Hunter Shirley,2 Robert Lamb,1 Shane Autry,2 Hammad Cheema,2 Kallol Talukdar,2 Tanya Jones,2 Jonah W. Jurss,2 Amala Dass,2 Nathan I. Hammer,2 Russell H. Schmehl,1 Charles Edwin Webster,3 and Jared H. Delcamp2
1Department of Chemistry, Tulane University, New Orleans, LA 70118 2Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
3Department of Chemistry, Mississippi State University, Starkville, MS 39762
Photochemical systems for hydrogen generation from protic solvents often involve a
chromophore, sacrificial electron donor, and a catalyst. Photocatalytic approaches in which
the chromophore is itself the active catalyst possess several advantages over
photosensitizer-dependent systems. For example, in sensitized catalysis, the excited
chromophore must first be reduced by the donor and then must pass the electron on to a
catalyst molecule. The inefficiency introduced by this physical requirement can be avoided
through design of systems in which electron transfer and accumulation of reducing/oxidizing
equivalents result from the photochemistry of the catalyst by itself. In this work, mechanistic
aspects of the behavior of the novel homogeneous chromophore/catalyst
[W(PyNHCPhCF3)(CO)4] (PyNHCPhCF3 = pyridyl N-heterocyclic carbene) are reported. In the
presence of a sacrificial reductant and the absence of a separate photosen sitizer (PS), the
system catalyzes reduction of protons to H2 in acetonitrile. Through IR spectroscopy, UV-Vis
spectroscopy, and electrochemistry, aspects of the mechanism of the proton reduction
reaction are clarified. The starting molecule is initially photolyzed with the loss of one
carbonyl. The tricarbonyl species is rapidly protonated, and, when kept in the dark,
thermally reacts with either the electron or proton donor. A second photon is then absorbed,
and the catalytic cycle is rapidly completed with the evolution of hydrogen. Analogous
tungsten-based molecules are currently being investigated for similar reactivity.
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New Insights into the Mechanism of the HER Catalyzed by (py-NHC-p-CF3Ph)W(CO)4
Robert W. Lamb,1 Aron J. Huckaba,2 Hunter Shirley,2 Steve Guertin,3 Shane
Autry,2 Hammad Cheema,2 Kallol Talukdar,2 Tanya Jones,2 Jonah W.
Jurss,2 Amala Dass,2 Nathan I. Hammer,2 Russell H. Schmehl,3 Jared H.
Delcamp,2 and Charles Edwin Webster1
1Department of Chemistry, Mississippi State University, Starkville, MS 39762 2Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
3Department of Chemistry, Tulane University, New Orleans, LA 70118
A hydrogen economy can be achieved if an efficient means of H2 production is realized via
the hydrogen evolution reaction (HER), 2H+(aq) + 2e– → H2(g). Herein, we report a
computational investigation of the catalysis and spectroscopy of a novel W–NHC complex
that can catalyze HER both electrochemically and photochemically without the use of a
photosensitizer. A mechanistic proposal will be presented.
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Oxidation of a CCC-NHC Pt(II) Complex via O-atom Transfer Reactions
Georgette M. Lang, Jason A. Denny, Vivek Dixit, Charles Edwin Webster,
and T. Keith Hollis
Department of Chemistry, Mississippi State University, Starkville, MS 39762
Terminal oxo complexes of late transition metals are exceedingly rare and pose an
interesting synthetic challenge. One approach is the utilization of O-atom transfer reagent
such as dimethyl dioxirane. Reaction of a CCC-NHC Pt(II) complex with dimethyl dioxirane
has led to many new observations including the isolation of a dimeric Pt(IV) species. DFT
calculations have been used to aid in the prediction of the structures of oxidation products
and intermediates involved in the reaction pathways.
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Electrocatalytic Reduction of Dinitrogen into NH3
Nalaka P. Liyanage and Jared H. Delcamp
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
The conversion of dinitrogen (N2) under ambient conditions is one of the most important
areas in chemistry. Since the establishment of a N2 reduction method (Haber-Bosch process)
by Haber and Bosch, industrial conversion of N2 to NH3 has been done on enormous scale
annually. Even though this process requires extreme reaction conditions and consumes
tremendous amount of energy, it is still the leading world fertilizer contributor. Thus,
attention has given towards the developing of molecular homogenous catalysts that can
efficiently act as nitrogen fixation catalyst under mild conditions. Among the homogenous
catalytic systems, the most commonly used metals are (Fe, Mo, Rh, Ir and W). The complexes
are typically in a low valent state and bear extremely electron donating ligands such as
tridentate phosphine containing ligands (PNP or PCP) that facilitate strong back-bonding to
N2. In all reported homogenous catalytic systems, only research towards the chemical
reduction by using single electron transfer reagents such as metallic sodium, cobaltocene,
and KC8 have being conducted. Ideally, the electrocatalytic reduction of N2 can be driven
without adding a sacrificial single electron reductant by coupling N2 reduction with water
oxidation. To the best of our knowledge, we have developed the first homogeneous
electrocatalytic system for N2 reduction with Fe(CO)5 as the molecular catalyst.
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Dual activated ruthenium complexes as anticancer prodrugs
Fengrui Qu,1 Kristina P. Martinez,2 Jessica L. Gray,1 John A. Lundeen,1
Russell H. Schmehl,2 and Elizabeth T. Papish1
1Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487 2Department of Chemistry, Tulane University, New Orleans, LA 70118
The search for new compounds which may rival or ideally surpass cisplatin as anticancer
drugs has been active for the past few decades. Several compounds containing ruthenium
have proven promising, especially three complexes which entered clinical trials. However,
metallo prodrugs that take advantage of the inherent acidity surrounding cancer cells have
yet to be developed. In this context, we will discuss a new class of pH-Activated Metallo
Prodrugs (pHAMPs) that are activated by light- and pH-triggered ligand dissociation. These
ruthenium complexes take advantage of a key characteristic of cancer cells and hypoxic solid
tumors (acidity) that can be exploited to lessen the side effects of chemotherapy. Five
ruthenium complexes of the type [(N,N)2Ru(PL)]2+ were synthesized, fully characterized, and
tested for cytotoxicity in cell culture (N,N = 2,2'-bipyridine (bipy), 1,10-phenanthroline
(phen), and 2,3-dihydro-[1,4]dioxino[2,3-f][1,10]phenanthroline (dop); and PL, the
photolabile ligand, = 6,6'-dihydroxybipyridine (6,6'-dhbp), 4,4'-dimethyl-6,6'-
dihydroxybipyridine (dmdhbp) and 4,4'-dihydroxybipyridine (4,4'-dhbp). Cytotoxicity
studies showed that complex 3 ([dop2Ru(6,6’-dhbp)]Cl2) is the most cytotoxic complex of
this series with IC50 values as low as 4 µM (with blue light) vs. two breast cancer cell lines.
Complex 3A is also selectively cytotoxic, with seven-fold higher toxicity towards cancerous
vs. normal breast cells. Phototoxicity indices (IC50 dark / IC50 light) with 3 were as high as 120,
indicated it is quite safe before being activated by light. These complexes demonstrate proof
of concept for dual activation by both low pH and blue light, thus establishing that a pHAMP
approach can be used for selective targeting of cancer cells. This work has been a
collaborative effort with Kim (Univ. of Alabama), Merino (Univ. of Cincinnati), and Paul
(Villanova University).
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Improved PEC activity for H2 evolution reaction from surface-passivated Cu2O photocathode
using bifunctional MoSx-catalyst
Pravin S. Shinde,1 Patricia Fontenot,2 Yanxiao Ma,1 James P.
Donahue,2 Russell H. Schmehl,2 Joseph L. Waters,3 Patrick Kung,3 Louis E.
McNamara,4 Nathan I. Hammer,4 Arunava Gupta,1,5 and Shanlin Pan1 1Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487
2Department of Chemistry, Tulane University, New Orleans, LA 70118
3Department of Electrical and Computer Engineering, The University of Alabama,
Tuscaloosa, AL 35487
4Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
5Department of Chemical and Biological Engineering, The University of Alabama,
Tuscaloosa, AL 35487
The p-type cuprous oxide (Cu2O) semiconductor can potentially address the looming energy
crisis because of its 18% theoretical promise in solar-to-fuel conversion efficiency. The
features such as low-cost, abundance, easy scale-up by a simple electrodeposition method,
greater visible light absorptivity (Eg=2.17 eV), and proper straddling of its energy band
edges for water reduction and oxidation potential levels make Cu2O a potential photocathode
to achieve visible-light-driven water reduction for H2 evolution. Unfortunately, the potential
levels for the self-reduction from Cu2O to Cu and self-oxidation to CuO are all within the
bandgap, which limits the stability of Cu2O in aqueous solution affecting its durability and
energy conversion. Therefore, Cu2O needs a protection to greatly extend its chemical stability
and durability. In this work, the Cu2O surface was coated with molybdenum sulfide (MoSx),
which has shown good prospects as both a protection layer and an electrocatalyst for
hydrogen evolution reaction due to its excellent stability and high electrocatalytic activity.
About 2 mm thick Cu2O film was electrodeposited on FTO by passing a total charge of ~4.5C
at −0.3V vs. Pt. Then, a thin layer of MoSx was achieved on asgrown Cu2O/FTO by spin-
coating a specially synthesized MoSx precursor followed by N2-annealing. Alternatively, the
proton reduction from spin-coated MoSx/FTO electrodes was studied to optimize spin
coating and post-processing conditions using several other MoSx precursor derivatives. The
photoelectrochemical measurement in 0.5 M Na2SO4 under standard 1 sun illumination
demonstrated higher activity for 3-layered (<50 nm thick) MoSx/Cu2O photocathode
fabricated at 450oC with a photocurrent on the order of 5 mA/cm2 at −0.2 V vs. RHE. Use of a
thin crystalline MoSx improved the dark current characteristics of Cu2O photocathode
meaning that MoSx coating not only protected Cu2O from reductive decomposition in the
electrolyte but also enhanced the catalytic activity to facilitate the proton reduction.
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Photophysical Characterization of Bipyridyl Hybrid
Oligomers: Examining Mixed Furan-Thiophene Systems
Using Spectroscopy and DFT Methods
April E. Steen, Suong T. Nguyen, Thomas L. Ellington, Gregory S. Tschumper,
Davita L. Watkins, and Nathan I. Hammer
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
The study of π-conjugated oligomers is of great interest due to their great potential use in
organic electronic devices, such as solar cells, light-emitting diodes, etc. Thiophene-
containing compounds have been extensively studied because of their good stability and
synthetic accessibility; however, studies on furan-containing compounds have shown that
these may also be viable, and perhaps even more preferred, substitutes. Furan-containing
compounds show greater solubility and increased fluorescence compared to their thiophene
analogues. Furan is also biodegradable and can be obtained from natural sources, making it a
good choice for mass produced products. These compounds, however, tend to be rather
unstable and possess high HOMO-LUMO gaps. In this study, hybrid oligomer systems
containing both furan and thiophene were synthesized and characterized using DFT methods
and spectroscopy in an attempt to determine if mixing the two heterocycles could create a
compound combining the positive attributes of the two individual cycles. One system in
particular was found to possess qualities that make it favorable for use in OEDs.
Feeding and Powering the World 2017: Building the Knowledge Base
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Plasmonic metal Au NP coated scanning probe nanoelectrode for spectroelectrochemistry and imaging
Yiliyasi Wusimanjiang and Shanlin Pan
Department of Chemistry, The University of Alabama, Tuscaloosa, Al, 35487
Tip-enhanced optical microscopy attracts the attention of scientific community in the past
decade due to its ability to image single nano-structures with high resolution by overcoming
diffraction limit. In this talk, a new strategy to fabricate single gold nanoparticle (Au NP)
attached plasmonic tip for spectroelectrochemistry and imaging will be presented. Initially, a
tungsten tip with ~ 30 nm wide apex was obtained by electrochemical etching of tungsten
wire (diameter: 100.0 µm) under -5.5 V (vs. Pt wire) direct current potential. This tip was
then insulated by electrochemical coating by a cathodic electropaint (HSR) and the apex of
the tip was exposed through curing at 195 °C. A single Au NP was deposited on the exposed
apex of the tip through electrochemical deposition. Tips with different Au NP sizes (100 nm –
1000 nm) were obtained by changing the electrochemical deposition time. Formation of the
Au NP on as constructed tip was confirmed by varies direct and indire ct ways such as
scanning electron microscopy, electrogenerated chemiluminescence, and cyclic
voltammetry.
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Feeding and Powering the World 2017: Building the Knowledge Base
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Dramatically Enhanced Hydride Protonation Rates following Photoinduced One Electron Reduction of Os(II)
Hydride Complexes
Rebecca Adams,1 Tod A. Grusenmeyer,1 Guangchao Liang,2
Charles E. Webster,2 and Russell H. Schmehl1
1Department of Chemistry, Tulane University, New Orleans, LA 70118
2Department of Chemistry, Mississippi State University, Starkville, MS 39762
Proton reduction to hydrogen gas is often catalyzed by transition metals; complete
understanding of the mechanism of catalyzed proton reduction is a major goal of researchers
in the solar fuels community. Metal hydride formation within the catalytic cycle of proton
reduction is often hypothesized; following metal hydride formation, protonation occurs to
yield H2. Quantifying the rate of metal hydride protonation in different redox states is
important to understanding the mechanism of catalysis. While the initially formed hydride
complex may be thermodynamically capable of reacting with protons to yield H2, other
reactions may compete kinetically with protonation. The large availability of reducing
equivalents in reductive photosystems allows for reduction of the metal hydride to compete
with protonation. Reduction of a metal hydride complex will produce a hydride with greater
reactivity relative to the initially formed hydride. The complex, [Os(phen)2(CO)H]+ (where
phen = 1,10-phenanthroline), has been studied by visible and infrared spectroscopy in acidic
acetonitrile solutions. The chromophore reacts thermally with protons in acetonitrile to yield
H2 and a vacant coordination site, typically filled by solvent. Protonation of the ground state
of the complex by trichloroacetic acid (pKa = 10.75 in CH3CN) occurs with a rate of 0.01
M-1s-1. The one-electron reduced complex can be obtained through excited state reduction by
1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole (BIH). The one-electron reduced
osmium hydride is stable over many seconds in the absence of protons. In an acetonitrile
solution containing trichloroacetic acid, the reduced hydride reacts with protons with a rate
of 2.8 x 107 M-1s-1. Insights toward the design of homogenous proton reduction catalysts may
be obtained through analysis of the free energy dependence of the protonation kinetics for a
series of Os(II) hydrides having different diimine ligands.
Sullivan, B. P.; Caspar, J. V.; Meyer, T. J.; Johnson, S. Organometallics 1984, 3 (8), 1241–1251.
Feeding and Powering the World 2017: Building the Knowledge Base
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Evidence of Iodine Binding with Thiophene Based Dyes in DSCs
Alexandra Baumann, Hammad Cheema, Adithya Peddapuram, Louis McNamara, Suong Nguyen, Davita Watkins, Nathan Hammer,
and Jared Delcamp
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
Six thiophene or furan dye analogs have been synthesized and used in dye-sensitized solar
cells (DSCs) to probe a possible iodine redox shuttle binding to the dyes while in DSC devices.
It has been previously hypothesized that dyes containing thiophene readily bind iodine in
functioning DSCs. Such bindings have been assigned to promote undesirable electron
transfer pathways, such as recombination of electrons in the TiO2 conduction band with the
redox shuttle held in close proximity to the TiO2 surface by the dye. This proposed
mechanism is suggested to lower the overall efficiency of the dye. In our study, direct
evidence of iodine binding can be seen with a simple thiophene dye via RAMAN spectroscopy
on films, while the furan analogue appears to show no binding. Larger thiophene dye
analogs exhibited indirect evidence of binding via UV-Vis in solution and on the surface,
electron lifetime studies on DSC devices, and devic e voltage output correlated with dye-
loading studies. To the best of our knowledge this study offers the first direct and supportive
indirect evidence of thiophene building blocks binding the redox shuttle. Interestingly, furans
show no evidence of binding.
Feeding and Powering the World 2017: Building the Knowledge Base
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Carbon Dioxide Reduction with Complexes of Ni(II) with Pincer Ligands Based on Pyridinol and
N-Heterocyclic Carbenes
Dalton B. Burks,1 Jared H. Delcamp,2 and Elizabeth T. Papish1
1Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487 2Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
There is a dire need to develop renewable sources of energy and fuels due to the inevitable
depletion of fossil fuels and the deleterious effects that burning fossil fuels has on the
environment. One potential source of alternative fuels is the reduction of carbon dioxide. The
reduction of carbon dioxide to carbon monoxide can be used to produce alternative fuels and
has the additional benefit of consuming CO2, a greenhouse gas. Photocatalytic CO2 reduction
is a green method of reducing carbon dioxide that uses solar power as the energy source.
Currently, the best photocatalysts for CO2 reduction in the literature use Ni(II) with
multidentate ligands. A Ni(II) complex with a tridentate pincer compound of
bis(imidazolyl)pyridinol was synthesized. When tested for photocatalytic CO2 reduction, it
achieves turnover number up to 10.6. Further efforts are ongoing to synthesize other
tridentate pincers ligands based on bis(benzimidazolyl)pyridinol.
Feeding and Powering the World 2017: Building the Knowledge Base
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Synthesis, Characterization, Photophysics, Ligand Rearrangement of CCC-NHC Pincer Nickel Complexes
used for Electrocatalytic Reduction of CO2
James D. Cope,1 Jason A. Denny,1 Robert W. Lamb,1 Louis E. McNamara,2 Nathan I. Hammer,2 Charles Edwin Webster,1
and T. Keith Hollis1
1Department of Chemistry and the Center for Computational Sciences, Mississippi State University, Starkville, MS, 39762
2Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
The metallation/transmetallation strategy has been successfully applied to the preparation
of CCC-NHC pincer nickel complexes. Manipulation of the coordination sphere lead to
cationic CCC-NHC pincer nickel complexes. It was discovered that exhibit polymorphism in
the solid state and have different colours and packing from the same sample. During
crystallization it was found that a rearrangement of the CCC-NHC ligand had occurred,
involving coupling of an NHC from two different ligands, which were oxidized. A couple of
these complexes were evaluated for electrocatalytic reduction of CO2 which improved in the
presence of water. Controlled potential electrolysis (CPE) was found to yield CO at 34% and
formate at 47% Faradaic efficiency (FE) selectively.
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Synthesis of new CNC pincer pre-ligands
Sanjit Das,1 Jared H. Delcamp,2 and Elizabeth T. Papish1
1Department of Chemistry, University of Alabama, Tuscaloosa, AL 35401 2Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
Transition metal complexes with tridentate CNC pincer ligand have recently found
application in catalytic activation of small molecules, e.g., the reduction of carbon dioxide in
addition to other organic transformation reactions. It is possible to tune catalytic and
electronic properties of these complexes widely by modifying the structure of the pincer
ligand. Structural variation of CNC pincer ligands and their effect in catalysis are not well
documented in the literature. Herein I report successful synthesis of two new pincer ligand
precursors 1,1'-(4-methoxypyridine-2,6-diyl)bis(3-phenyl-1H-benzo[d]imidazol-3-ium)-
ditriflate with aromatic wing-tip groups and 1,1'-(4-hydroxypyridine-2,6-diyl)bis(3-methyl-
1H-imidazol-3-ium)ditriflate which can tautomerize between pyridinol and pyridone forms.
Metal complexes with these new ligands will be studied for photocatalytic CO2 reduction.
Feeding and Powering the World 2017: Building the Knowledge Base
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Photocatalytic and Electrocatalytic Reduction of CO2 to CO with Ni-Pyridyl-Pincer-NHCs
Shakeyia Davis, Roberta R. Rodrigues, Dalton Burks, Elizabeth T. Papish,
and Jared H. Delcamp
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
The production of renewable fuels by the conversion of solar energy into chemical energy is
a challenge. Photocatalytic and electrocatalytic conversion of CO2 to usable fuel precursors
are approaches to overcoming these challenges. The two-electron reduction of carbon
dioxide to carbon monoxide is an appealing process because CO can be used as a commodity
chemical in industrial processes. Many molecular CO2 reduction catalysts have been reported
and commonly use expensive late transition metals. Recently, the pyridyl-NHC ligands have
gained attention in catalytic systems due to the strong donating ability of the NHC to
strengthen the nucleophilicity of the transition metal center and the withdrawing ability of
the pyridine ring allowing electron storage. This promotes the catalytic activity. In this study,
novel Ni molecular catalyst, which bears a pyridyl-pincer-N-heterocyclic carbene ligand
(NHC) have been studied. The e lectrocatalytic and photocatalytic reduction of CO2 with this
complex has been evaluated by cyclic voltammetry and simulated solar photocatalysis.
Feeding and Powering the World 2017: Building the Knowledge Base
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Synthesis and Electrochemical Characterization of Bismuth Halide Double Perovskite Films
Tyra Douglas, Matthew Davenport, Yanxiao Ma, Jared Allred, and Shanlin Pan
Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487
Increasing global energy demand has escalated the need for clean alternatives to fossil fuels.
Solar energy harvested using perovskite solar cells is one promising clean alternative.
Although lead halide perovskite solar cells have exhibited promising conversion efficiencies,
their toxicity and instability hinder the commercial implementation of this technology.
Bismuth halide double perovskites, such as Cs2AgBiBr6 and (CH3NH3)2AgBiBr6, have been
synthesized and studied and show promise as a replacement. However, due to the low
solubility of the precursor salts, tradition perovskite synthesis methods cannot be used to
synthesize films. In this work, non-tradition synthesis methods were explored to fabricate
bismuth double perovskite films, and the electrochemical proprieties are reported.
Feeding and Powering the World 2017: Building the Knowledge Base
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Photocatalytic Hydrogen Evolution by Homogeneous Molybdenum Sulfide Complexes
Patricia R. Fontenot, Bing Shan, Russell H. Schmehl, and James P. Donahue
Department of Chemistry, Tulane University, New Orleans, LA 70118
In this work a series of complexes containing terminal disulfide edges as well as bridging
disulfide, or mono-sulfide bridges were prepared and characterized for their ability to
reduce protons from water in a photochemical system. These molybdenum complexes
[Mo3S13]2-, [Mo3S7(S2CNEt2)3]1+ , [Mo3S7(S2CNiBu2)3]1+, [Mo3S4(S2CNiBu2)4]0 were studied in
a photosystem containing [Ru(bpy)3]2+ as the chromophore, 4-N,N,-trimethylanaline (TMA)
as reversible quencher in relay with triethylamine (TEA) as sacrificial electron donor, and
using only H2O as the source of protons. Using the same set of conditions it was found that
[Mo3S7(S2CNEt2)3]1+ was the most active hydrogen evolution catalyst studied in this
photosystem. MALDI-TOF mass spectrometry was used to study the photoreaction progress
over time, and the [Mo3S7(S2CNEt2)3]1+ was found to be converted to the
[Mo3S4(S2CNEt2)3]1+ cluster. Since then, the newest derivative of the catalyst,
[Mo3S7(S2CNiBu2)3]1+, was found to be even more active, with a TON >300, for hydrogen
production due to enhanced solubility. Direct synthesis of [Mo3S4(S2CNiBu2)3]1+, and
[Mo3S4(S2CNiBu2)4]0 has also been completed and the photolysis measurements are still
ongoing. From the results thus far, it is clear that disulfide edges are not necessary for
hydrogen generation. All hydrogen produced was confirmed and analyzed by gas
chromatography assay.
Feeding and Powering the World 2017: Building the Knowledge Base
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Development and study of novel ruthenium complexes as potential dual-activated anticancer prodrugs: the role of
pH in uptake and the use of cytotoxic ligands
Jessica L. Gray,1 Fengrui Qu,1 Seungjo Park,2 Kristina Martinez,3 Russell H. Schmehl,3 Yonghyun Kim,2 and Elizabeth T. Papish1
1Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487 2Department of Chemical and Biological Engineering, The University of Alabama,
Tuscaloosa, AL 35487 3Department of Chemistry, Tulane University, New Orleans, LA 70118
Per the American Cancer Society’s Cancer Facts and Figures there were an estimated 1.6
million new cases of cancer in 2016. Many treatments are currently available however they
exhibit serious side effects due to poor selectivity. Efforts to create safer anticancer therapies
and limit undesired side effects include the development of site-directed treatments. We
have developed a series of ruthenium complexes of the type [Ru(N,N’)2(6,6’-
dihydroxybipyridine)]2+ as potential anticancer prodrugs that are cytotoxic when exposed to
light but maintain low toxicity in the dark. The rate of photodissociation is increased in acidic
conditions but the complexes are relatively stable at neutral pH values. Since cancer cells are
known to have a lower extracellular pH due to increased metabolism, we hypothesize that
our complexes exhibit selective cytotoxicity when in the presence of cancer cells and can be
activated by photodynamic therapy (PD T). Presented here are the investigations into several
complexes of the type [Ru(N,N’)2(6,6’-dihydroxhybipyridine)]2+ as potential anticancer
prodrugs activated in the presence of light. Our studies indicate that rate of cellular uptake
has an impact on toxicity. This is being investigated by determining the distribution
coefficient in an octanol/water system as a function of pH. A new compound containing the
cytotoxic ligand, 5-cyanouracil, has also been synthesized to develop a potential prodrug.
Feeding and Powering the World 2017: Building the Knowledge Base
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Synthesis of Osmium (II) Carbonyl Complexes; Influence of Electron Withdrawing and Donating Ligands on
Spectroscopic Properties
Audrey Griffith, Rebecca Adams, and Russell Schmehl
Department of Chemistry, Tulane University, New Orleans, LA 70118
Direct synthesis of complexes that serve as model catalytic intermediates can be useful in
mechanistic studies. For example, the synthesis of metal hydrides has allowed for hydride
protonation (MH + H+ M+ + H2) rates to be assessed under various conditions. Osmium (II)
carbonyl complexes containing polypyridyl ligands have been synthesized via the extension
of methods reported by Meyer et al in 1984.1 Complexes of the type cis-
[Os(pp)2(CO)(L)]n+ (pp = polypyridyl ligands similar to 1,-10-phenanthroline (phen) or 2,2’-
bipyridine (bpy)); (L = CH3CN, Cl, or H) have been obtained and characterized by 1H NMR and
ESI-MS. These complexes are of particular interest spectroscopically due to their long-lived
excited states and easily tuned redox potentials. Cyclic voltammetry has been performed to
measure their oxidation and reduction potentials, resulting in the generation of a series
(using the substituted ligands) with reduction potentials spanning a 550 mV range.
Photophysical properties of the complexes will be correlated to the one-electron reduction
potentials, and the visible and infrared absorption spectra of this series will be compared.
References:
1. Sullivan, B. P.; Caspar, J. V.; Meyer, T. J.; Johnson, S. Organometallics 1984, 3 (8), 1241–1251.
Feeding and Powering the World 2017: Building the Knowledge Base
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CCC-NHC Pincer Ta Complexes: Synthesis ad Reactivity
Theodore R. Helgert, Jason A. Denny, T. Keith Hollis, and C. Edwin Webster
Department of Chemistry, Mississippi State University, Starkville, MS 39762
A series of tantalum complexes featuring the CCC-NHC pincer ligand have been synthesized.
Complexes have been characterized by NMR, Elemental Analysis, and X-Ray crystallographic
analysis. The latest catalytic results and reactivity with hydrazine derivatives will be
reported.
Feeding and Powering the World 2017: Building the Knowledge Base
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Measuring Electron Injection Efficiencies for Optimization of Dye-Sensitized Solar Cells
Leigh Anna Hunt, Roberta R. Rodrigues, Yanbing Zhang, Adithya
Peddapuram, Louis McNamara, Jared H. Delcamp, and Nathan I. Hammer
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38655
Dye-sensitized solar cells (DSCs) are a low cost and promising alternative to standard
photovoltaic cells. One major issue with DSCs is the enhancement of sensitization for use in
the near-infrared region of the electromagnetic spectrum. In order to investigate the kinetics
of electron injection, fluorescence lifetime measurements were carried out for a series of
dyes to evaluate electron injection efficiencies. Fluorescence lifetime studies both in solution
and on TiO2 films provide insights into evaluating the performance and optimizing the
structures of dyes for use in DSC devices.
Feeding and Powering the World 2017: Building the Knowledge Base
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Synthesis and Electrochemical Characterization of NixPy Covered Copper Nanoneedles for Efficient
Hydrogen Evolution
Nelly Kaneza and Shanlin Pan
Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487
With increasing need of more stable and efficient catalysts for hydrogen evolution reaction
(HER), transition metal phosphides have shown promising HER performance. In this study, a
series of nickel phosphide (NixPy) nanoparticles will be grown onto copper nanoneedles (Cu
NNs) using a combination of electrochemical deposition and phosphidation reaction. The
synthesized electrocatalysts will be characterized by high resolution transmission electron
microscopy (HRTEM) and scanning electron microscopy (SEM), X-ray diffraction (XRD), and
X-ray photoelectron spectroscopy (XPS). Their HER performance will then be examined by
linear sweep voltammetry (LSV). This easy-to-follow synthesis procedure will provide a
rapid, practical and cost-effective method to improve the electrocatalytic activities of
NixPy nanoparticles and their promising application in clean energy technologies.
Feeding and Powering the World 2017: Building the Knowledge Base
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Photochemical hydrogen generation using single
component Pt(II) bis-pyridyl benzene chromophore-
catalyst system
Aditya Kulkarni and Russell H. Schmehl
Department of Chemistry, Tulane University, New Orleans, LA 70118
Production of hydrogen from visible irradiation of solutions that contain only a chromophore
and an electron donating source is quite rare. Recent examples include
[Rh20,0(dfpma)3(PPh3)(CO)] (dfpma = MeN(PF2)2)1,2 and [PtCl(tpy)]Cl (tpy = 2,2’:6’ ,2’’-
terpyridine)3. The former system uses a hydrohalic acid (HX) and splits it to produce H2 and
the latter involves photoinduced reduction of water in the presence of a sacrificial electron
donor like EDTA in water at pH 5. Using unique Pt(II) NCN (bis-pyridyl benzene) type
complexes prepared in our labs, hydrogen generation was observed in 9:1 DMF:water in the
presence of triethylamine (TEA). The quantum yield of hydrogen generation was ~2 % after
2 hours of irradiation. The turnover rate was 0.15 min-1 and hydrogen generation continued
at this rate beyond the initial irradiation period of 2 hours. The complexes are strongly
luminescent in solution, but the emission is efficiently quenched by TEA. Control
experiments indicate that both the chromophore and TEA are required for H2 production.
Addition of Hg does not suppress H2 formation, suggesting the absence of colloidal Pt in the
photolysis solution. The system also suggests to be making hydrogen in presence of oxygen
Transient spectroscopic experiments provide insight into the mechanistic details of
hydrogen formation in these systems and the 1 electron reduced species has been identified.
References
1A.F. Heyduk and D.G. Nocera. Science 293 (2001) 1639.
2A.J. Esswein, A.S. Veige and D.G. Nocera. J.Am.Chem.Soc. 127 (2005) 16641.
3R. Okazaki, S. Masaoka and K. Sakai. Dalton Trans. (2009) 6127.
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Improvement of Hematite Thin Film Photoactivity by Au, Ag and Co Doping for Solar Water Splitting
Yanxiao Ma, Pravin Shinde, and Shanlin Pan
Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487
N-type semiconductor, nanostructured hematite (α-Fe2O3) has been found to be a promising
photocatalyst for solar water splitting due to its good stability, absorption in the visible
region, low cost, and favorable band gap of 2.2 eV. However, its low conductivity and short
hole diffusion length limit the photoactivity of hematite. In this work, Au doped hematite, Ag
– hematite nanocomposite and Co doped Ag – hematite nanocomposite were screened by
scanning photoelectrochemical microscopy (SPECM) to find the optimum condition for
oxygen evolution reaction under visible light irradiation on both Ti and F-doped tin oxide
(FTO) substrate. The doped hematite materials were also characterized by scanning electron
microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Au and Ag were both
found to exist as nanoparticles in the doped hematite nanostructures. Au doped hematite
was found little enhancement in photocurrent up to 3% of Au. Decrease in photocurrent was
found with 4-10% of Au doping. The composition of nanocomposite with 40% Ag – 60% Fe
(atomic percentage) showed a significant improvement in photocurrent, about 10 times
higher than pristine hematite films. Co doped hematite and Co doped 40% Ag – 60%
Fe nanocomposite showed significant decrease in photocurrent with Co composition as little
as 0.1%.
Feeding and Powering the World 2017: Building the Knowledge Base
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Thienopyrroledionebased Photosensitizers for High Voltage Dyesensitized Solar Cells
Adithya Peddapuram, Roberta R. Rodrigues and Jared H. Delcamp
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
Dye-sensitized solar cells (DSCs) are an attractive renewable energy technology in part due
to their relatively low cost of production and the potential to provide sufficient energy to
meet the world’s energy needs. Currently, DSC devices using organic dyes hold a record
14.3% power conversation efficiency (PCE). Careful pairing of the photosensitizer and redox
couple used in the DSC device can allow for either high efficiency for the generation of
electricity or for the generation of high voltage devices used to power chemical processes
such as electrochemical catalysis, like CO2 reduction, water oxidation and nitrogen reduction.
Voltages up to 1.45 V have been reported in literature using a Br-/Br3- redox couple. In this
work we synthesized D-π-A dyes (D = donor, A = Acceptor) using a thienopyrroledione (TPD)
π-bridge and the commonly used cyanoacrylic acid anchor. Alkylated donor moieties are
used for course tuning of the dye ground-state oxidation potential. Additionally, the use of
multiple alkyl chains helps diminish counterproductive electron transfer pathways in
devices. Devices employing the TPD-based dyes and an Fe(bpy)3 redox shuttle demonstrate
high open circuit voltages up to 1.33 V.
Feeding and Powering the World 2017: Building the Knowledge Base
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Excited State Dynamics of Charge Transfer for
Tris-heteroleptic Ruthenium Complexes
Barry C. Pemberton,1 Stephen L. Guertin,1 James E. Yarnell,2 Son N. Nguyen,1 Felix N. Castellano,2 and Russel H. Schmehl1
1Department of Chemistry, Tulane University, New Orleans, LA 70118
2Department of Chemistry, North Carolina State University, Raleigh, NC 27695
This work highlights the interplay between single and multistep intermolecular charge
transfer processes in an (LL)M(III)-Donor system and a similar absorption transition in the
photoexcited M(II)-Donor complex, (LL-)M(III)-Donor. We’ve synthesized a series of
terpyridyl-bipyridyl-dimethylamino pyridyl tris heteroleptic ruthenium(II) complexes that
exhibit unique absorbance characteristics between 750-1150 nm following one-electron
oxidation or pulsed laser excitation into a metal-to-ligand charge transfer (MLCT) state.
Along with temperature dependence, spectroelectrochemistry, and steady-state
photophysics, we have used visible pump-probe ultrafast kinetics to observe significant rise
time for complexes containing dimethylamino pyridine and not for the pyridine analogs. We
believe this unique absorbance band can be assigned to the extended hole-conjugation
between the metal center and dimethylamino ligand.
Feeding and Powering the World 2017: Building the Knowledge Base
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A Novel Wide Band Gap Dye Producing 1.4 V DSC Devices with an Iron Redox Shuttle
Roberta R. Rodrigues, Hammad Cheema, and Jared H. Delcamp
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
The development of high voltage solar cells is an attractive way to use sun light to power
electrocatalysts for water oxidation, power electrocatalyst for CO2 reduction to generate
carbon based fuels that are fossil-free, and to power consumer electronics. Herein we report
a single junction dye-sensitized solar cell (DSC) employing for the first time an iron redox
mediator (Fe(bpy)3+3/+2) in conjunction with a novel wide band gap dye (RR9). This system
generates a high photovoltage of 1.42 V. To the best of our knowledge, this system is the
highest photovoltage achieved by a single junction DSC device without metal oxide doping.
This system introduces a new, tunable alternative to achieving high photovoltages. The
Fe(bpy)2+3/+2 redox shuttle was found to transfer electrons efficiently via incident photon-to-
current conversion efficiency measurements to an oxidized RR9 with only a 200 mV
energetic driving force for electron transfer.
Feeding and Powering the World 2017: Building the Knowledge Base
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Home-built SECM for the Screening of Photocatalytic Arrays
Lyndi Strange and Shanlin Pan
Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487
Scanning electrochemical microscopy (SECM) is scanning probe technique that measures the
local electrochemical activity of a substrate. The technique works by scanning an ultra-
microelectrode (UME) tip across the surface of a substrate, where electrochemical activity is
monitored. The technique was credited to Allen J. Bard, the father of modern
electrochemistry, in 1989. The first commercial SECM instrument was available in 1999 by
CH Instruments, which caused a dramatic influx of research groups that use SECM for a
variety of studies. This project sought to construct a home-built SECM that can produce
good-quality images. The SECM consists of three separate controllers (x, y, and z) connected
to precise motors, three-axis stage, probe, potentiostat, and custom electrochemical cell. The
controllers allow the motors to move the probe precisely over the substrate. The
potentiostat controls the voltage applied to the substrate, which generates the current
detected at the tip and read by the multimeter. The output of the multimeter is programmed
into LabVIEW where a three-dimensional plot of the substrate electrochemical activity is
obtained. For the study of photocatalyst arrays, an optical fiber was used as a probe to find
the photocatalytic hotspot. Good-quality imaging was performed using the home-built
setup. For future project, we plan to incorporate an absorbance measurement for the
photocatalyst spots.
Feeding and Powering the World 2017: Building the Knowledge Base
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Spectroscopic and Computational Study of Chlorine Dioxide/Water Interactions
Sarah Sutton, Walter E. Cleland, Jr., and Nathan Hammer
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
Chlorine dioxide, a stable free radical, plays a very important role in water purification. It is a
strong oxidizing agent that is used to oxidize harmful metals and is found in unpurified
ground water. Because it also possesses strong antimicrobial properties, chlorine dioxide is
emerging as a leading disinfectant for medical equipment. Although chlorine dioxide is
primarily used to eliminate harmful substances in aqueous environments, very little is
known about how it interacts with water itself. In a spectroscopic study, UV-vis and Raman
spectra, supported by DFT methods, begin to reveal these important intermolecular
interactions. Raman spectra of varying concentrations of ClO2 in water reveal there is no shift
in the fundamental stretching mode at 945 cm-1, indicating there is no charge transfer
between ClO2 and water as the number of intermolecular interactions increases. The lack of
charge transfer is also observed in methanol and chloroform solutions of ClO2. A comparison
of computed Raman spectra of ClO2/(H2O)x (x=1-4) shows a red shift of the fundamental
stretching mode, indicating charge transfer.
Feeding and Powering the World 2017: Building the Knowledge Base
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Computational Studies of the Hydrogen Bonding Interactions of Hydroxyethyl Ethers
Ashley Williams, Steven Davis, and Nathan Hammer
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
The isoenzymatic form of microsomal cytochrome P450, CYP2E1, is involved in the
formation of oxygen free radicals, specifically hydroxyethyl ether. Chronic alcohol abuse has
been found to induce larger levels of CYP2E1 in the liver, thus increasing production of these
harmful free radicals. Generation of the hydroxyethyl ether oxygen free radicals occurs
during the metabolism of ethanol in microsomes. The hydrogen-bonding interactions of
hydroxyethyl ethers with water have yet to be analyzed, and information regarding the
interactions with water can be applied directly to biological systems. Here, we employ
computational chemistry to study hydroxyethyl ether complexes in micro-solvated networks
of varying complexity.
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Photoluminescence Imaging Study of Perovskite Thin Film Using Scanning Confocal Microscope
Jeetika Yadav and Shanlin Pan
Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487
Organic-inorganic hybrid perovskites have attracted immense interest as effective
photovoltaic materials driven by their beneficial properties such as excellent power
conversion efficiencies, low cost as well as flexibility in material fabrication development,
excellent electronic and optical properties such as high absorption coefficient, ambipolar
nature, long diffusion length and band gap. Among hybrid perovskites, the
methylammonium lead triiodide (CH3NH3PbI3) has stood out due to rapid increase in Power
Conversion Efficiency (PCE) as well as high photovoltaic performance in just a couple of
years. The issues associated with CH3NH3PbI3 perovskites are stability and surface
degradation overtime, moisture sensitivity caused by hydrolyzation which hinders the mass
production, environmental problems due to heavy metal lead and lifetime. Spatial variation
in methylammonium lead tri iodide (CH3NH3PbI3) translates into variations in its
fluorescence. The perovskite not only act as a visible light absorber but also hole transporter
hence to study its fluorescence properties is interesting. In this work, we studied
fluorescence of CH3NH3PbI3 using a 405nm laser (25mW Modu-Laser) which was passed
through neutral density filter to reduce the power of incident beam for confocal laser
scanning fluorescence microscopy. An electron multiplying charge coupled device (EM-CCD)
was used to detect the fluorescence. The confocal optical configuration is achieved by small ≈
180μm area of the avalanche photodiodes APDs (Perkin Elmer) and the pinhole aperture in
the emission light path. This system removes the out-of-focus light by rejecting the light
above and below the image plane. The as-synthesized CH3NH3PbI3 generated both green
(527nm) and red (744nm) fluorescence. To detect red and green fluorescence separately,
two filters were placed in front of both avalanche photodiodes APDs (Perkin Elmer). The
issues affecting fluorescence of perovskites are stability since methylammonium lead
triiodide (CH3NH3PbI3) decomposes overtime into lead iodide (PbI2), methylamine (CH3NH2)
and hydroiodic acid (HI).
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Electro- and Photocatalytic CO2 Reduction with a Well-Defined Dinuclear Rhenium Complex: Comparing the Monometallic and Cooperative Bimetallic Pathways
Weiwei Yang, Nalaka P. Liyanage, Sayontani Sinha Roy, Casey A. Carpenter,
Winston Pitts, Rebekah L. Nelson, Jared H. Delcamp, Jonah W. Jurss
Department of Chemistry & Biochemistry, University of Mississippi, Oxford, MS 38677
Roughly 85% of the world’s energy is derived from burning fossil fuels that generate
greenhouse gases and other airborne pollutants. Carbon dioxide is the chief component of
this waste stream and a leading contributor to global warming. It also represents a readily
accessible C1 building block for value-added chemicals. In this context, we have designed an
anthracene-bridged dinuclear rhenium complex for electro- and photocatalytic CO2
reduction to CO. Related by hindered rotation of each metal site to either side of the
anthracene, cis and trans conformers have been isolated. Higher turnover frequencies and
greater durability has been achieved relative to the parent catalyst, Re(bpy)(CO)3Cl. The
results of recent mechanistic investigations of these systems will also be presented.
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Synthesis and Characterization of CCC-NHC Pincer Platinum Complexes
Min Zhang, Eric Van Dornshuld, Vivek Dixit, Jason A. Denny, Charles Edwin
Webster, and T. Keith Hollis
Department of Chemistry, Mississippi State University, Starkville, MS 39762
New symmetric and unsymmetric CCC-NHC pincer Pt complexes were synthesized by a
metalation/transmetalation methodology to extend our previously reported strategy. The
photophysical properties (absorption, emission, lifetime, and quantum yield) of these new Pt
complexes were studied. Density functional theory (DFT) and time-dependent density
functional theory (TD-DFT) computations were used to study the ground and excited state
structures, energetics, and electronic properties including absorption, emission. The
molecular structures of Pt complexes were determined by X-ray crystallography. 195Pt NMR
chemical shifts were collected. The electron-donating ability of meridional tridentate ligands
(square planar CCC-NHC ligands) could easily be evaluated and compared for the first time
by 195Pt NMR chemical shift.
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Katie Echols
Mississippi State University
Outreach Coordinator
Outreach activities take place throughout the year at different locations within Mississippi,
Alabama, and Louisiana. Outreach is directed at K-12, community college, and university
levels, in addition to local community outreach in the form of science cafés and public service
announcements. Outreach activities are coordinated by Ms. Katie Echols.
Women in STEM Seminars:
This program raises student awareness of various STEM careers and the women who are successful in those fields. Women who are positive role models in STEM careers to speak at various institutions such as PUIs, HBCUs, and secondary schools. Each speaker discusses the path to her STEM career, what girls today can do to be successful in STEM fields, and opportunities available for students interested in getting involved in STEM. Three or Four seminars are conducted each year.
November 10, 2015: East Mississippi Community College (Speaker: Megan Holmes) November 19, 2015: Itawamba Community College (Speaker: Lindsey Brown) January 20, 2016: Tougaloo College (Speaker: Denise Cornelius) February 27, 2017: Northwest MS Community College (Speaker: Dr. Syndey Murphy March 24, 2017: Columbus High School, Columbus, MS (Speaker: Ashli Brown, State Chem Lab) March 30, 2017: Baton Rouge Community College (Speaker: Dr. Anne Robinson)
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Science Cafés:
Science Cafés increase knowledge of material science research and provide opportunities for public engagement and discussion of important research topics. Science cafés are lively events that take place in informal settings like a coffee house. They are open to everyone and include a conversation with a researcher on a particular topic. Scientists discuss current research directly related to the water-energy-food nexus and the role chemistry can play in solving the problem. At least four café’s are held each year, targeting college students and adults with one café a year specifically for high school students. We work with teachers at the local high schools to promote and encourage the student’s attendance. Participants are asked to complete short surveys so data can be collected on the participants’ increased knowledge on the topic.
January 21, 2016: 929 Café, Starkville, MS (Speaker: Todd French) January 27, 2016: High Point Café, Oxford, MS (Speaker: Jared Delcamp) April 14, 2016: Nehemiah's, Tuscaloosa, AL (Speaker: David A. Dixon) April 26, 2016: Tulane University Lavin Bernick Center (Speaker: Russ Schmehl) November 2, 2016: Tulane University Lavin Bernick Center (Drs. Doug Chrisey and Tom Sherry)
November 3, 2016: Starbucks Coffee, Tuscaloosa, AL (Speaker: Dr. Elizabeth Papish)
November 29, 2016: High Point Café, Oxford, MS (Speaker: Gregory Tschumper)
April 18, 2017: Starkville Coffee, Starkville, MS (Speaker: Keith Hollis)
.Middle and High School Science Teacher Summer Workshops:
These annual workshops increase teachers’ teaching efficacy and knowledge of content related to material science and the water-energy-nexus theme. They last two weeks each summer and include 15 teachers. The location of the workshop will change annually in order to target different geographical areas. Workshops were held at Mississippi State University in 2016 and in New Orleans in 2017. Upcoming ones include Alabama in 2018 and the Mississippi Delta in 2019. Pictures from previous workshops are on the next page.
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Research Experience for Undergraduates (REU) and College Teacher Program:
Undergraduate students and college teachers are supported each summer to perform
research in the laboratories of senior personnel. Applications are accepted on the program
website.
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Clean Energy Harvesting:
Training and education activities closely integrated with the concept of clean energy harvesting and conversion are underway at the University of Alabama. The goal is to help improve clean energy and nanotechnology program for underrepresented minority K-12 school teachers and students in Alabama’s rural Black Belt Counties and undergraduate students by providing them with hands-on research projects and classroom education modules.
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F. Qu, S. Park, K. Martinez, J. L. Gray, F. Shazna Thowfeik, J. A. Lundeen, A. E. Kuhn, D. J. Charboneau, D. L. Gerlach, M. M. Lockart, J. A. Law, K. L. Jernigan, N. Chambers, M. Zeller, N. A. Piro, W. S. Kassel, R. H. Schmehl, J. J. Paul, E. J. Merino, Y. Kim, and E. T. Papish, “Ruthenium Complexes are pH-Activated Metallo Prodrugs (pHAMPs) with Light Triggered Selective Toxicity Towards Cancer Cells,” Inorganic Chemistry, in press.
J. D. Cope, J. A. Denny, R. W. Lamb, L. E. McNamara, N. I. Hammer, C. E. Webster, and T. K. Hollis, “Synthesis, Characterization, Photophysics and a Ligand Rearrangement of CCC-NHC Pincer Nickel Complexes: Colors, Polymorphs Emission and Raman Spectra,” Journal of Organometallic Chemistry, DOI: 10.1016/j.jorganchem.2017.05.046 (2017).
Y. Zhang, S. A. Autry, L. E. McNamara, S. T. Nguyen, N. Le, P. Brogdon, D. L. Watkins, N. I. Hammer, and J. H. Delcamp“Near-Infrared Fluorescent Thienothiadiazole Dyes with Large Stokes Shifts and High Photostability,” Journal of Organic Chemistry, DOI: 10.1021/acs.joc.7b00422 (2017).
J. D. Cope, N. P. Liyanage, P. J. Kelley, J. A. Denny, E. J. Valente, C. E. Webster, J. H. Delcamp, T. K. Hollis, “Electrocatalytic Reduction of CO2 with CCC-NHC Pincer Nickel Complexes,” Chemical Communications, accepted (2017).
H. K. Box, T. O. Howell, W. E. Kennon, G. A. Burk, H. U. Valle, T. K. Hollis, “An efficient route to unsymmetrical bis(azolium) salts: CCC-NHC pincer ligand complex precursors,” Tetrahedron, 73, 2191-2195 (2017). DOI: 10.1016/j.tet.2017.02.020
S. Siek, D. B. Burks, D. L. Gerlach, J. M. Tesh, C. R. Thompson, F. Qu, J. E. Shankwitz, R. M. Vasquez, N. S. Chambers, G. J. Szulczewski, D. B. Grotjahn, C. E. Webster, and E. T. Papish, “Iridium and Ruthenium Complexes of NHC and Pyridinol Derived Chelates as Catalysts for Aqueous Carbon Dioxide Hydrogenation and Formic Acid Dehydrogenation: The Role of the Alkali Metal,” Organometallics, 36, 1091-1106 (2017). DOI: 10.1021/acs.organomet.6b00806
A. Panikar, Z. Shan, S. Pan, and A. Gupta, “Photocatalytic Water Oxidation at Bismuth Vanadate Thin Film Electrodes Grown by Direct Liquid Injection Chemical Vapor Deposition Method International Journal of Hydrogen Energy,” International Journal of Hydrogen Energy, (2017). DOI: 10.1016/j.ijhydene.2016.12.113
A. Yengantiwar, S. Palanivel, A. Panikar, Y. Ma, S. Pan, and A. Gupta, “Direct Liquid Injection Chemical Vapor Deposition of Molybdenum Doped Bismuth Vanadate
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Photoelectrodes for Efficient Solar Water Splitting,” Journal of Physical Chemistry C, (2017). DOI: 10.1021/acs.jpcc.6b12710
S. Siek, N. A. Dixon, and E. T. Papish, “Electrochemical Reduction of Ttz Copper(II) Complexes in the Presence and Absence of Protons: Processes Relevant to Enzymatic Nitrite Reduction. (TtzR,R’ = tris(3-R, 5-R’-1, 2, 4-triazolyl)borate),” Inorganica Chimica Acta, 459, 80 (2017). DOI: 10.1016/j.ica.2017.01.021
N. N. Sreeramulu, L. McNamara, N. I. Hammer, and H. Rathnayake, “A versatile synthesis to novel binary reactive groups functionalized silsesquioxane microparticles,” Science Advances Today, 3, 25266 (2017).
H. Cheema and J. H. Delcamp, “Harnessing Photovoltage: Effects of Film Thickness, TiO2 Nanoparticle Size, MgO and Surface Capping with DSCs,” ACS Applied Materials and Interfaces,” 9, 3050–3059 (2017). DOI: 10.1021/acsami.6b11456
Kevin M. Williams, Morgan Gruner, Julia Gensheimer, Alexandra Wright, Morgan Blair, Shane A. Autry, and Nathan I. Hammer, “Partial displacement of a triamine ligand from a platinum(II) complex after reaction with N-acetylmethionine,” Inorganica Chimica Acta, 458, 163-170 (2017). DOI: 10.1016/j.ica.2017.01.010
J. L. Gray, D. L. Gerlach, and E. T. Papish, “Crystal structure of [(1,4,7,10-tetraazacyclododecane)copper(II)] perchlorate,” Acta Crystallographica Section E: Crystallographic Communications, E73, 31-34 (2017). DOI: 10.1107/S2056989016019563 Jessica K. White, Russell H. Schmehl, and Claudia Turro, “An Overview Of Photosubstitution Reactions Of Ru(II) Imine Complexes And Their Application In Photobiology And Photodynamic Therapy,” Inorganica Chimica Acta, 454, 7-20 (2017). DOI: 10.1016/j.ica.2016.06.007
J. Wang, J. Waters, P. Kung, S. Kim, J. T. Kelly, L. E. McNamara, N. I. Hammer, A. Gupta, and S. Pan, “A Facile Electrochemical Reduction Method for Improving Photocatalytic Performance of α-Fe2O3 Photoanode for Solar Water Splitting,” ACS Applied Materials and Interfaces, 9, 381-390 (2017). DOI: 10.1021/acsami.6b11057 J. Wang, A. Gupta, and S. Pan, ”A Facile Template-free Electrodeposition Method for Vertically Standing Nanorods on Conductive Substrates and Their Applications for Photoelectrochemical Catalysis,” International Journal of Hydrogen Energy (2016). DOI: 10.1016/j.ijhydene.2016.10.072
R. L. Letterman, N. J. DeYonker, T. J. Burkey, and C. E. Webster, “Calibrating Reaction Enthalpies: the Use of Density Functional Theory and the Correlation Consistent Composite Approach in the Design of Photochromic Materials,” Journal of Physical Chemistry A (2016). DOI: 10.1021/acs.jpca.6b09278
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C. J. Saint-Louis, L. L. Magill, J. A. Wilson, A. R. Schroeder, S. E. Harrell, N. S. Jackson, J. A. Trindell, S. Kim, A. R. Fisch, L. Munro, V. J. Catalano, C. E. Webster, P. P. Vaughan, K. S. Molek, A. K. Schrock, and M. T. Huggins, “The Synthesis and Characterization of Highly Fluorescent Polycyclic Azaborine Chromophores,” Journal of Organic Chemistry, 81, 10955-10963 (2016). DOI: 10.1021/acs.joc.6b01998
A. J. Huckaba, A. Yella, L. E. McNamara, A. E. Steen, J. S. Murphy, C. A. Carpenter, G. D. Puneky, N. I. Hammer, M. K. Nazeeruddin, M. Grätzel, and J. H. Delcamp, “Molecular Design Principles of Near-Infrared Absorbing and Emitting Indolizine Dyes,” Chemistry - A European Journal, 22, 15536-15542 (2016). DOI: 10.1002/chem.201603165
R. Adams and R. Schmehl, “Micellar Effects on Photoinduced Electron Transfer in Aqueous Solutions Revisited: Dramatic Enhancement of Cage Escape Yields in Surfactant Ru(II) Diimine Complex/[Ru(NH3)6]2+ Systems,” Langmuir, 32, 8598-8607 (2016). DOI: 10.1021/acs.langmuir.6b02193
T. R. Helgert, X. Zhang, H. K. Box, J. A. Denny, H. U. Valle, A. G. Oliver, G. Akurathi, C. E. Webster, and T. K. Hollis, “Extreme Pi-Loading as a Design Element for Accessing Imido Ligand Reactivity. A CCC-NHC Pincer Tantalum Bis(imido) Complex: Synthesis, Characterization, and Catalytic Oxidative Amination of Alkenes,” Organometallics, 35, 3452-3460 (2016). DOI: 10.1021/acs.organomet.6b00216
N. P. Liyanage, H. A. Dulaney, A. J. Huckaba, J. W. Jurss, and J. H. Delcamp, “Electrocatalytic Reduction of CO2 to CO With Re-Pyridyl- NHCs: Proton Source Influence on Rates and Product Selectivities,” Inorganic Chemistry, 55, 6085-6094 (2016). DOI: 10.1021/acs.inorgchem.6b00626
K. Bhattacharya, Q. Tejani, and S. Pan, “Construction and Characterization of p-type heterojunction CuO|CuBi2O4 photocathode electrode for photoelectrochemical reduction of water as sustainable source of energy,” Joshua, The Journal of Science and Health at The University of Alabama, 13, 17-21 (2016).
J. Hitt, D. Trotman, and S. Pan, “Synthesis of α-FeOOH and CoPi Thin Films for use as Catalysts in Electrochemical Water Oxidation and Efficiency Comparison to Known Effective Catalysts,” Joshua, The Journal of Science and Health at The University of Alabama, 13, 12-16 (2016).
P. Brogdon, L. E. McNamara, A. Peddapuram, N. I. Hammer, and J. H. Delcamp, ”Toward Tightly Bound Carboxylic Acid-Based Organic Dyes for DSCs: Relative TiO2Binding Strengths of Benzoic Acid, Cyanoacrylic Acid, and Conjugated Double Carboxylic Acid Anchoring Dyes,” Synthetic Metals, 222, 66-75 (2016). DOI: 10.1016/j.synthmet.2016.03.031
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N. Kaneza, J. Zhang, A. Panikar, Z. Shan, A. Gupta, H. Liu, M. Vasiliu, S. H. Polansky, D. A. Dixon, R. E. Adams, R. H. Schmehl, and S. Pan, “Electrochemical and Spectroscopy Studies of BODIPY-Thiophene-Triphenylamine Based Dyes for Dye-Sensitized Solar Cells,” Journal of Physical Chemistry C, 120, 9068-9080. DOI: 10.1021/acs.jpcc.6b01611
W. D. Clark, K. N. Leigh, C. E. Webster, and T. K. Hollis, “Experimental and Computational Studies of the Mechanisms of Hydroamination/Cyclisation of Unactivated α,ω-Amino-alkenes with CCC-NHC Pincer Zr Complexes,” Australian Journal of Chemistry, 69, 573-582 (2016). DOI: 10.1071/CH15779
H. U. Valle, G. Akurathi, J. Cho, W. D. Clark, A. Chakraborty, and T. K. Hollis, “CCC-NHC Pincer Zr Diamido Complexes: Synthesis, Characterisation, and Catalytic Activity in Hydroamination/Cyclisation of Unactivated Amino-Alkenes, -Alkynes, and Allenes,” Australian Journal of Chemistry, 69, 565-572 (2016). DOI: 10.1071/CH15795
S. W. Reilly, C. E. Webster, T. K. Hollis, and H. U. Valle, “Transmetallation from CCC-NHC Pincer Zr Complexes in the Synthesis of Air-Stable CCC-NHC Pincer Co (III) Complexes and Initial Hydroboration Trials,” Dalton Transactions, 45, 2823-2828 (2016). DOI: 10.1039/C5DT04752H
A. J. Huckaba, E. A. Sharpe, and J. H. Delcamp, “Photocatalytic Reduction of CO2 with Re-Pyridyl-NHCs,” Inorganic Chemistry, 55, 682-690 (2016). DOI: 10.1021/acs.inorgchem.5b02015
L. E. McNamara, N. Liyanage, A. Peddapuram, J. S. Murphy, J. H. Delcamp, and N. I. Hammer, “Donor-Acceptor-Donor Thienopyrazines via Pd-Catalyzed C-H Activation as NIR Fluorescent Materials,” Journal of Organic Chemistry, 81, 32-42 (2016). DOI: 10.1021/acs.joc.5b01958
S. Pan, J. Liu, and C. M. Hill, “Observation of Local Redox Events at Individual Au Nanoparticles Using Electrogenerated Chemiluminescence Microscopy,” Journal of Physical Chemistry C, 119, 27095–27103 (2015). DOI: 10.1021/acs.jpcc.5b06829
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Name Role E-Mail Address School Mentor
Adithya Peddapuram Grad [email protected] OleMiss Delcamp
Aditya Kulkarni Grad [email protected] Tulane Schmehl
Alexandra Baumann Grad [email protected] OleMiss Delcamp
Ambar Bahadur Shrestha Grad [email protected] Alabama Papish
Angela Hairston UG [email protected] Alabama Papish
April Steen Grad [email protected] OleMiss Hammer
Asala Issa UG [email protected] OleMiss Jurss
Ashley Williams Grad [email protected] OleMiss Hammer
Audrey Griffith UG [email protected] Tulane Schmehl
Austin Dorris Grad [email protected] OleMiss Hammer
Barry Pemberton PD [email protected] Tulane Schmehl
Cameron Smith UG [email protected] OleMiss Hammer
Casey Carpenter UG [email protected] OleMiss Delcamp
Chance Boudreaux Grad [email protected] Alabama Papish
Cole Mccreary UG [email protected] Tulane Schmehl
Colleen Chernowsky UG [email protected] OleMiss Jurss
Cyrus Picou Jr. UG [email protected] OleMiss Hammer
Dalton B. Burks Grad [email protected] Alabama Papish
Divina Miranda Teacher [email protected] Tulane Schmehl
Hammad Cheema PD [email protected] OleMiss Delcamp
Eric Van Dornshuld PD [email protected] MSU Webster
Fengrui Qu PD [email protected] Alabama Papish
Genevieve Halingten-Verville UG [email protected] OleMiss Hammer
Georgette Lang PD [email protected] MSU Hollis
Guangchao Liang Grad [email protected] MSU Webster
Hunter Hessler UG [email protected] MSU Hollis
Jackson Gunter UG [email protected] Alabama Pan
James Cope Grad [email protected] MSU Webster
Jason Denny PD [email protected] MSU Hollis
Jeetika Yadav Grad [email protected] Alabama Pan
Jessica Gray Grad [email protected] Alabama Papish
Jordan Wilson UG [email protected] Alabama Pan
Joseph Lee Grad [email protected] OleMiss Jurss
Kallol Talukdar Grad [email protected] OleMiss Jurss
Kayla Milano Grad [email protected] OleMiss Jurss
Kyle Quist UG [email protected] OleMiss Hammer
Leah Wallace UG [email protected] OleMiss Hammer
Leigh Anna Hunt Grad [email protected] OleMiss Hammer
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Lillian Mathews Teacher [email protected] Alabama Pan
Lizhu Chen Grad [email protected] OleMiss Jurss
Louis McNamara PD [email protected] OleMiss Hammer
Lyndi Strange Grad [email protected] Alabama Pan
Madeline Mixon UG [email protected] OleMiss Jurss
Mattie Braselton UG [email protected] OleMiss Delcamp
Michael Esposito UG [email protected] Tulane Schmehl
Min Zhang Grad mz273@msstate,edu MSU Webster
Nalaka Liyanage Grad [email protected] OleMiss Delcamp
Nelly Kaneza Grad [email protected] Alabama Pan
Orrion Kuykendall UG [email protected] Alabama Papish
Patricia Fontenot Grad [email protected] Tulane Donahue
Phillip Brogdon Grad [email protected] OleMiss Delcamp
Pravin Shinde PD [email protected] Alabama Pan
Rebecca Adams Grad [email protected] Tulane Schmehl
Robert Lamb Grad [email protected] MSU Webster
Roberta Rodrigues Grad [email protected] OleMiss Delcamp
Sanjit Das Grad [email protected] Alabama Papish
Sarah Altman UG [email protected] Alabama Papish
Sarah Sutton UG [email protected] OleMiss Hammer
Sayontani Sinha Roy Grad [email protected] OleMiss Jurss
Shakeyia Davis Grad [email protected] OleMiss Delcamp
Shane Autry Grad [email protected] OleMiss Hammer
Shelby Ruiz UG [email protected] MSU Hollis
Stephen Guertin Grad [email protected] Tulane Schmehl
Theodore Helgert PD [email protected] MSU Hollis
Tyler Woodby UG [email protected] MSU Hollis
Tyra Douglas Grad [email protected] Alabama Pan
Victoria Arau UG [email protected] Alabama Pan
Vivek Dixit PD [email protected] MSU Webster
Vivienne Tenev HS [email protected] OleMiss Jurss
Weiwei Yang Grad [email protected] OleMiss Jurss
Yanxiao Ma Grad [email protected] Alabama Pan
Yiliyasi Wusimanjiang PD [email protected] Alabama Pan
Yingjie Cheng HS [email protected] OleMiss Jurss
Zachary VanOrman UG [email protected] Alabama Pan