School of Materials Science and Engineering Summer Vacation Research Scholarship Projects/SMSE SVRT...
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1 Summer Vacation Research Scholarship Projects School of Materials Science and Engineering Supervisor Dr Damia Mawad Email [email protected] Project Title A self-doped poly(ethylenedioxy thiophene) (PEDOT) for enhanced electronic stability Project Description The aim of the project is to synthesise a self-doped conjugated polymer that is water soluble and has extended electronic stability in physiological media. Conjugated polymers are synthetic macromolecules capable of conducting both electronically and ionically. In a self-doped conjugated polymer, the dopant (counterion) is covalently bound to the backbone (Scheme 1) and its diffusion into its surrounding is restricted, enhancing the electronic stability of the polymer. Conditions such as a heart attack disrupt low resistance pathways between neighbouring cells and consequently interrupt the bioelectric signal propagating along the tissue. Flexible organic bioelectronics are being explored as biomaterial-based approaches applied on the biotic/abiotic interface to electro-couple with injured electroresponsive tissues and restore the electric signal. Due to their intrinsic electroactive nature, conjugated polymers are being considered as the structural material in bioelectronic devices. However, the clinical application of conjugated polymers has been mainly hindered by their short term operational lifetime in physiological conditions due to loss of dopant. Designing a self-doped polymer with the counterion in close proximity to the EDOT monomer (one carbon away) has the potential to solve the aforementioned limitation. Our group focuses on the development of conjugated polymers with tailored chemistries. We then incorporate and test these novel materials into device configurations to produce bioelectronics with enhanced electronic performance in physiological conditions. The student will develop the synthetic strategy to produce the functional EDOT precursor followed by its polymerization. The student will also get the opportunity to gain experience in characterisation techniques of electroactive materials.
Transcript of School of Materials Science and Engineering Summer Vacation Research Scholarship Projects/SMSE SVRT...
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Summer Vacation Research Scholarship Projects
School of Materials Science and Engineering
Supervisor Dr Damia Mawad
Email [email protected]
Project Title A self-doped poly(ethylenedioxy thiophene) (PEDOT) for enhanced electronic stability
Project Description
The aim of the project is to synthesise a self-doped conjugated polymer that is water soluble and has extended electronic stability in physiological media. Conjugated polymers are synthetic macromolecules capable of conducting both electronically and ionically. In a self-doped conjugated polymer, the dopant (counterion) is covalently bound to the backbone (Scheme 1) and its diffusion into its surrounding is restricted, enhancing the electronic stability of the polymer. Conditions such as a heart attack disrupt low resistance pathways between neighbouring cells and consequently interrupt the bioelectric signal propagating along the tissue. Flexible organic bioelectronics are being explored as biomaterial-based approaches applied on the biotic/abiotic interface to electro-couple with injured electroresponsive tissues and restore the electric signal. Due to their intrinsic electroactive nature, conjugated polymers are being considered as the structural material in bioelectronic devices. However, the clinical application of conjugated polymers has been mainly hindered by their short term operational lifetime in physiological conditions due to loss of dopant. Designing a self-doped polymer with the counterion in close proximity to the EDOT monomer (one carbon away) has the potential to solve the aforementioned limitation. Our group focuses on the development of conjugated polymers with tailored chemistries. We then incorporate and test these novel materials into device configurations to produce bioelectronics with enhanced electronic performance in physiological conditions. The student will develop the synthetic strategy to produce the functional EDOT precursor followed by its polymerization. The student will also get the opportunity to gain experience in characterisation techniques of electroactive materials.
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Supervisor Dr Kevin Laws
Email [email protected]
Project Title Magnesium-based bulk amorphous alloys for personal electronic devices: (In collaboration with Seoul National University)
Project Description
With continuous pressure to develop lighter and thinner personal electronic devices for higher functionality, transportability and user comfort, key manufacturers such as Samsung, have begun to utilise light-weight magnesium alloys as a chassis material for the internal framework and componentry of their devices. Over the past 10 years at UNSW we have developed many new Mg-based BMGs with large critical casting sizes. These alloys far exceed the strength of regular
magnesium, aluminium and titanium alloys allowing for even thinner and lighter sections to be used in these devices. However the major downside of Mg-based BMGs is their lack of fracture toughness or brittle nature. Recently we have developed a range of toughened Mg-based BMGs & composites that may provide a viable, cost-effective replacement for the existing Mg-based internal componentry of personal electronic devices.
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Supervisor Dr Kevin Laws
Email [email protected]
Project Title Aluminium-based amorphous alloys for aerospace applications: (Supported by the United States Air Force Research Laboratories)
Project Description
The United States Air Force has a dedicated materials and manufacturing directorate focussed on the design and development of new cutting-edge materials for future use. One key material of interest in aircraft design is aluminium due to its relatively high strength to weight properties and high corrosion resistance leading to extended service life in the field. With the exceptionally improved mechanical properties of bulk metallic glasses over conventional crystalline alloys the challenge of
designing and manufacturing aluminium-based BMGs is currently high on their agenda and currently being undertaken at UNSW. This is a fundamentally challenging project and considered as one of the largest challenges in the metallic glass community due to the high crystallisation rate of aluminium alloys.
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Supervisor Dr Kevin Laws
Email [email protected]
Project Title Gold-Silver-Palladium-Platinum based bulk amorphous alloys for commemorative coins: (In collaboration with the Royal Australian Mint)
Project Description
In 2012 at UNSW, we discovered the world’s first and only silver-based bulk metallic glass alloy. This discovery generated considerable interest in the electronics, photonics and jewellery communities due to the high conductivity, reflectivity, hardness and thermomechanical processability of these unique alloys. Currently we are developing a range of precious metal metallic glasses specifically to optimise their glass-forming ability, elevated temperature processability and corrosion resistance for use as commemorative coins and jewellery applications with the Royal Australian Mint. This project will explore new gold, silver, palladium and platinum based alloy compositions and test their superplastic formability in the supercooled liquid state.
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Supervisor Dr Kevin Laws
Email [email protected]
Project Title High entropy brasses & bronzes for auto engine bearings: (Supported by Advanced Alloy Holdings & AMPCO METALS)
Project Description
The current role of brasses and bronzes in the world today is subtly astounding. The keys in your pocket (often chrome-plated), the hinges that your front door swings on - your door knobs and their internal lock
mechanisms; your bathroom fixtures are chromed or polished brass, the zippers on your clothes, gears in gear motors, automotive and heavy machinery bearings, military munitions and highly corrosion resistant marine fixtures and world coin currencies to name but a few. Without doubt, since the bronze-age, brasses and bronzes are the most widely utilised family of materials on the planet. At UNSW we have recently patented a new family of high entropy
brasses & bronzes containing copper, nickel, manganese, zinc, aluminium and tin. We are now developing new low-cost, hgh-performance high entropy brasses and bronzes alloys with industrial partners for various applications
including; hard bronzes for slide bearing and forging dies, low friction brasses for automotive bearings and deep drawing brasses for flat, bar, plate or sheet machine and forming-stock for mainstream and marine applications.
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Supervisor Dr Kevin Laws
Email [email protected]
Project Title High entropy precious metal alloys for jewellery & magnetic applications (In Collaboration with the Royal Australian Mint & Swiss Federal Institute of Technology ETH Zurich)
Project Description
At UNSW we have recently patented two new families of high entropy precious metal alloys from the gold-silver-palladium-platinum-copper family and another from the platinum-palladium-cobalt-nickel-chrome family. The gold-silver-palladium-platinum-copper alloys exhibit high reflectivity with strength, ductility and hardness exceeding current fine silver, sterling
silver and white gold alloys. These alloys are also the first alloys to successfully alloy gold and platinum in solid solution, whilst maintaining useful and workable ductility. Here, an alloy development project, aligned with interests of the Royal Australian Mint is on offer working within this alloy system. In addition, the
platinum-palladium-cobalt-nickel-chrome alloys also have very high strength and hardness and due to the addition of cobalt and spin polarisation of platinum and palladium they also exhibit hard magnetic properties which opens these alloys to other applications such as ‘levitating jewellery’ or hard memory storage capabilities. The full magnetic characterisation work for this alloy family shall be carried out.
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Supervisor Professor Charles C Sorrell
Email [email protected]
Project Title Bioresorbable Ceria Photocatalysts for Cancer Treatment
Project Description
Current research funded by the Australian Research Council and a UNSW Scientia Scholarship involves the development of photocatalysts for cancer treatment. As shown in the figure below, it has been demonstrated that osteosarcoma cancer cells can be induced to take up photocatalytic nanoceria (CeO2), which can be activated by X-rays or ultrasound, thus destroying the cancer cells from within. However, a follow-up challenge is the engineering of the nanoparticles so that they ultimately are resorbed in the physiological environment (pH 7.4) following photocatalytic activation and consequent cancer cell destruction. Both the solubility and the photocatalytic efficiency of nanoceria can be enhanced by increasing its oxygen vacancy concentration [1,2], which can be done by (a) increasing the solution temperatures during precipitation [3] and (b) iron doping [4]. The project will combine these two approaches by the following principal procedures: (1) Preparation of cerium-based solutions with a range of controlled doping levels of iron ≤4 at% (2) Precipitation of monodisperse nanoceria at a range of temperatures ≤100°C (3) Characterisation (X-ray diffraction, transmission electron microscopy, and BET surface area) (4) Determination of oxygen vacancy concentrations using X-ray photoelectron spectroscopy [5] (5) Determination of in vitro solubility in simulated body fluid This work is capable of generating one publication in a good refereed journal. [1] D. Channei, S. Phanichphant, A. Nakaruk, S.S. Mofarah, P. Koshy, and C.C. Sorrell, “Aqueous and Surface Chemistries of Photocatalytic Fe-Doped CeO2 Nanoparticles”, Catalysts, 7 [2] Paper 45 {23 pp.} (2017). [2] Z. Liu, X. Li, M. Mayyas, P. Koshy, J.N. Hart, and C.C. Sorrell, “Growth Mechanism of Ceria Nanorods by Precipitation at Room Temperature and Morphology-Dependent Photocatalytic Performance”, CrystEngComm, 19 [32] 4766-4776 (2017). [3] Z. Liu, X. Li, P. Koshy, J.N. Hart, and C.C. Sorrell, “Morphology-Dependent Photocatalytic Properties of CeO2 Nanoparticles”, in preparation. [4] D. Channei, B. Inceesungvorn, N. Wetchakun, S. Phanichphant, A. Nakaruk, P. Koshy, and C.C. Sorrell, “Photocatalytic Activity under Visible Light of Fe-Doped CeO2 Nanoparticles Synthesized by Flame Spray Pyrolysis”, Ceram. Int., 39, 3129-3134 (2013).
Green Nanoparticles Red Cell Membrane Blue Nucleus Pink Lysosomes
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Supervisor Professor Nagarajan Valanoor
Email [email protected]
Project Title Pulsed laser deposition epitaxy of complex oxide materials
Project Description
At UNSW, we have recently installed an advanced pulsed laser deposition tool which is suited for complex oxide thin film epitaxy. What makes this system really powerful is that it has in-situ Reflective High Energy Electron Diffraction (RHEED) capabilities. RHEED oscillations can be used to precisely terminate interfaces and control the surface chemistry within the monolayer. However the entire process requires very careful specimen preparation as well as instrumentation alignment. In this project the student will take oxide substrates and process them such as to optimize the surface chemistry. This will be followed by PLD-RHEED synthesis of a perovskite materials (ABO3). The PLD-RHEED deposited thin film will be investigated via HRTEM and high- resolution XRD. Once the first layer has been synthesized with optimum conditions, the student will then optimize the deposition conditions to fabricate alternating ultra-thin (1-4 nm) multilayers of varying compositions. Such layer- by-layer epitaxy approaches will be used to discover novel interfacial characteristics that may be useful for nanoelectronic devices. The project is highly hands-on and will require close cooperation with a postgraduate student. Each run can take up to 8-12 hours and therefore a student with an inherent motivation to further specialize in thin film epitaxy will be ideally suited for the project.
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Supervisor Professor Nagarajan Valanoor
Email [email protected]
Project Title Magnetic oxide nanostructures using pulsed laser deposition
Project Description
We are interested in the fabrication of nanostructured metal oxides for a variety of energy applications using a thin film deposition technique called Pulsed Laser Deposition. Using film fabrication conditions analogous to atomic layer-by layer fabrication and by playing with growth ambients we can make a host of nanostructures – from smooth stepped thin films to nanopyramids to nanotriangles. We have synthesized untitary and binary metal oxides of Fe, Ni, Mn and Co for magnetic applications. This in addition to the lab’s continued emphasis on the development of ultrathin oxide films. The project will focus on the synthesis of nanostructured magnetic oxides in sub-100 nm size range on metal oxide substrates. Currently noble metal nanocrystals and clusters on oxide supports are in widespread use as active materials for heterogeneous catalysis and gas sensing. However, noble metals are expensive and hence there is a significant push to seek alternative nanostructured materials as alternative cost effective solutions. Naturally the size and shape of the nanocrystals are important factors that determine physical and chemical properties such as luminescence, conductivity, and catalytic activity. Further magnetic nanocrystals are an important class of functional oxides that possess interesting magnetic, magnetoresistive, and magneto-optical properties. These properties are also a strong function of the shape, size, and crystallinity of the nanocrystals, and consequently, the ability to synthesize high-density magnetic oxide nanocrystals with controlled spacing, shape, and size has emerged as a dominant theme in nanomaterials science and technology.
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Supervisor Professor Nagarajan Valanoor
Email [email protected]
Project Title Development of Pb-free ferroelectric thin films by sol-gel processes
Project Description
A majority of the functional piezoceramics currently used are lead (Pb-) based. There is now a growing concern about the environmental effects of Pb and therefore there is a strong push for Pb-free piezoceramics. In the project we will investigate bismuth ferrite (BiFeO3-BFO) based alloys as potential Pb- free piezoceramics. Our team has recently optimized synthesis routes for BFO thin films via sol-gel techniques. Now we are interested in looking at dopants as well as role of film texture. These films will be synthesized on suitable perovskite substrates. The student will work closely with a research associate on the synthesis aspect; there is an opportunity to learn thin film fabrication and characterization techniques. Bulk of the work is complete characterization of the synthesized thin films using high-resolution XRD and Scanning Probe Microscopy. The student will use the technique of Piezoresponse Force Microscopy to quantify piezoelectric behaviour. An industrial partner has been identified and there is a possibility for interactions with this partner. For more details about this aspect, students are advised to meet me. Strong experimental skills and an interest in solid-state crystal chemistry are highly recommended for successful completion.
