making solar cells d. venkataraman (dv) department of chemistry umass amherst [email protected] june...
TRANSCRIPT
Making Solar Cells
D. Venkataraman (DV)Department of Chemistry
Umass [email protected]
June 29, 2010
Efficiency of Photovoltaic Cells Depend on Absorption in the Solar Spectrum Charge SeparationCharge MobilityCharge Collection
Photovoltaic CellsPhotovoltaic Cells
Exciton
Active Material
Source: National Renewable Energy Laboratory
Organic Photovoltaic Devices
Organic Photovoltaic Devices StabilityStabilityEfficiencyEfficiency
CostCost
End-User ApplicationEnd-User
Application
Konarka KonarkaHome Depot/BP Solar
What is the Problem?What is the Problem?
Si or III-V Cells
Exciton diffusion distance >100 nm
Excitons loosely bound
Organic/Hybrid/Dye-sensitized
Exciton diffusion distance <10 nm
Excitons tightly bound (Frenkel Excitons)
Low dielectric constant
10 nm
Gregg, B. A., Excitonic solar cells. Journal of Physical Chemistry B 2003, 107 (20), 4688-4698.
Active Material-conjugated molecules
/polymers
Active Material-conjugated molecules
/polymers
StabilityStabilityEfficiencyEfficiency CostCost
Active LayerMorphologiesActive Layer
Morphologies
Electrode/Active Layer Interfaces
Electrode/Active Layer Interfaces
Device Fabrication/Encapsulation
Device Fabrication/Encapsulation
Intrinsic
Extrinsic
OMe
O
PCBM – [6,6]-phenyl-C61-butyric acid methyl ester
SH
C6H13
SS
C6H13
C6H13
Hm
Poly(3-hexylthiophene) (P3HT)
Organic Photovoltaic CellsOrganic Photovoltaic Cells
Bulk Heterojunction CellsEfficiency ~ 5%
Padinger, F.; Rittberger, R. S.; Sariciftci, N. S., Effects of postproduction treatment on plastic solar cells.Advanced Functional Materials 2003, 13 (1), 85-88. Ma, W. L.; Yang, C. Y.; Gong, X.; Lee, K.; Heeger, A. J. "Thermally stable, efficient polymer solar cells with nanoscale control of the interpenetrating network morphology," Advanced Functional Materials 2005, 15, 1617-1622.
100 nm
