Ryan Fagenson_CEEMposter
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-2.1 eV -4.0 eV -5.1 eV -5.6 eV Device Performance of Bulk Heterojunction Organic Solar Cells Utilizing a Polymer Acceptor Ryan Fagenson Mentor: Jes Sherman Faculty Advisor: Michael Chabinyc Department of Materials, UC Santa Barbara Why Organic Solar Cells? • Inexpensive • Lightweight • Easy to Process • Flexible • Printable • Use in Tandem Cells Project Description Spiro-OMeTAD N2200 Experimental Methods Cathode (Al) Active Layer (Spiro- OMeTAD:N2200) Hole Transport Layer (PEDOT:PSS) Anode (ITO) Glass Results/Data Power Conversion Efficiency (PCE) -Power conversion efficiency (PCE) describes how efficient the cell is at converting light energy into electricity. External Quantum Efficiency (EQE) Conditions we varied to optimize performance: 1. Spin speed of active layer coating - 600, 750, & 900 RPM 2. Donor to acceptor ratio in solution - 1:1, 2:1, & 1:2 Conclusions/Future Work Acknowledgements Thanks to: -Jes Sherman for being a fantastic mentor -Nancy Eisenmenger for help with testing setup -Chris Liman for data analysis assistance -Andrew Jacobs for AFM help • PCBM is the electron acceptor in the highest-efficiency organic cells to date • N2200 does not work as a donor in a cell with PCBM due to its low-lying LUMO, which doesn’t allow an electron to transfer • We investigated the use of N2200 as an acceptor instead, with Spiro-OMeTAD as the donor Spiro-OMeTAD N2200 strates in for cleaning Substrate goes here, PEDOT:PSS solution dropped on and substrate rotated to spread out and dry Same process as last step, but inside nitrogen glove box and active layer solution added Substrate loaded here, coated side facing down to add aluminum contacts Schematic of final product e l ect r o n Donor Acceptor E n e r g y Efficiency=Voc*Jsc*FF Absorption peak around 375 nm Absorption peaks around 400, 700 nm EQE Wavelength (nm) -External quantum efficiency (EQE) measures the fraction of incident light photons that get converted to charge carriers (which generate electricity). Atomic Force Microscopy (AFM) -Atomic force microscopy (AFM) creates a picture of the surface of the cell, showing the variations in height. Our small molecule donor/polymer acceptor system worked, but at low efficiency. Fabricate devices using other polymers as the acceptor that have HOMO/LUMO levels that match our donor molecule better. Test devices, calculate efficiencies and other characteristics , and repeat with other polymers. LUMO
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Transcript of Ryan Fagenson_CEEMposter
-2.1 eV
-4.0 eV
-5.1 eV-5.6 eV
Device Performance of Bulk Heterojunction Organic Solar Cells Utilizing a Polymer Acceptor
Ryan FagensonMentor: Jes Sherman
Faculty Advisor: Michael ChabinycDepartment of Materials, UC Santa Barbara
Why Organic Solar Cells?
• Inexpensive • Lightweight• Easy to Process• Flexible• Printable• Use in Tandem Cells
Project Description
Spiro-OMeTAD
N2200
Experimental Methods
Cathode (Al)Active Layer
(Spiro-OMeTAD:N2200)
Hole Transport Layer (PEDOT:PSS)Anode (ITO)
Glass
Results/DataPower Conversion Efficiency (PCE)
-Power conversion efficiency (PCE) describes how efficient the cell is at converting light energy into electricity.
External Quantum Efficiency (EQE)
Conditions we varied to optimize performance:
1. Spin speed of active layer coating - 600, 750, & 900 RPM2. Donor to acceptor ratio in solution - 1:1, 2:1, & 1:2
Conclusions/Future Work Acknowledgements
Thanks to: -Jes Sherman for being a fantastic mentor -Nancy Eisenmenger for help with testing setup -Chris Liman for data analysis assistance -Andrew Jacobs for AFM help
• PCBM is the electron acceptor in the highest-efficiency organic cells to date
• N2200 does not work as a donor in a cell with PCBM due to its low-lying LUMO, which doesn’t allow an electron to transfer
• We investigated the use of N2200 as an acceptor instead, with Spiro-OMeTAD as the donor
Spiro-OMeTAD
N2200
Substrates in for cleaning
Substrate goes here, PEDOT:PSS solution dropped on and substrate rotated to spread out and dry
Same process as last step, but inside nitrogen glove box and active layer solution addedSubstrate loaded here, coated
side facing down to add aluminum contacts
Schematic of final product
electron
Donor Acceptor
Energy Efficiency=Voc*Jsc*FF
Absorption peak around 375 nm
Absorption peaks around 400, 700 nm
EQE
Wavelength (nm)
-External quantum efficiency (EQE) measures the fraction of incident light photons that get converted to charge carriers (which generate electricity).
Atomic Force Microscopy (AFM)
-Atomic force microscopy (AFM) creates a picture of the surface of the cell, showing the variations in height.
Our small molecule donor/polymer acceptor system worked, but at low efficiency.
Fabricate devices using other polymers as the acceptor that have HOMO/LUMO levels that match our donor molecule better.
Test devices, calculate efficiencies and other characteristics, and repeat with other polymers.
LUMO
