TY - JOUR
T1 - Modular construction of P3HT/PCBM planar-heterojunction solar cells by lamination allows elucidation of processing-structure-function relationships
AU - Kim, Jong Bok
AU - Guan, Ze Lei
AU - Lee, Stephanie
AU - Pavlopoulou, Eleni
AU - Toney, Michael F.
AU - Kahn, Antoine
AU - Loo, Yueh Lin
N1 - Funding Information:
This work was supported by the Photovoltaics Program at ONR ( N00014-11-10328 ) and the SOLAR Initiative at the NSF ( DMR-1035217 ). Partial funding by an NSF-sponsored MRSEC through the Princeton Center for Complex Materials ( DMR-0819860 ) and by the Department of Energy ( DE-FG02-04ER46165 ) is also gratefully acknowledged. Portions of this research were carried out at the Stanford Synchrotron Radiation Lightsource user facility operated by Stanford University on behalf of the US Department Energy, Office of Basic Energy Sciences.
PY - 2011/11
Y1 - 2011/11
N2 - Contrary to polymer solar cells with bulk-heterojunction active layers, devices with planar-heterojunction active layers allow the decoupling of active layer phase separation from constituent crystallization, and their relative influence on device performance. We fabricated planar-heterojunction devices by first processing the electron donor and electron acceptor in isolation; they were subsequently laminated across the donor-acceptor interface to establish electrical contact. Thermal annealing was intentionally avoided after lamination to maintain the pristine charge transfer interface. Lamination thus obviates the need for solvent orthogonality; more importantly, it provides independent process tuning of individual organic semiconductor layers, ultimately allowing control over constituent structural development. We found the short-circuit current density of planar-heterojunction solar cells comprising poly(3-hexyl thiophene), P3HT, and [6,6]-phenyl-C61-butyric acid methyl ester, PCBM, as the electron donor and acceptor, respectively, to be generally independent of the annealing history of P3HT. On the contrary, thermal annealing PCBM prior to lamination mainly led to a reduction in short-circuit current density. This deterioration is correlated with the development of preferentially oriented PCBM crystals that hinders electron transport in the vertical direction.
AB - Contrary to polymer solar cells with bulk-heterojunction active layers, devices with planar-heterojunction active layers allow the decoupling of active layer phase separation from constituent crystallization, and their relative influence on device performance. We fabricated planar-heterojunction devices by first processing the electron donor and electron acceptor in isolation; they were subsequently laminated across the donor-acceptor interface to establish electrical contact. Thermal annealing was intentionally avoided after lamination to maintain the pristine charge transfer interface. Lamination thus obviates the need for solvent orthogonality; more importantly, it provides independent process tuning of individual organic semiconductor layers, ultimately allowing control over constituent structural development. We found the short-circuit current density of planar-heterojunction solar cells comprising poly(3-hexyl thiophene), P3HT, and [6,6]-phenyl-C61-butyric acid methyl ester, PCBM, as the electron donor and acceptor, respectively, to be generally independent of the annealing history of P3HT. On the contrary, thermal annealing PCBM prior to lamination mainly led to a reduction in short-circuit current density. This deterioration is correlated with the development of preferentially oriented PCBM crystals that hinders electron transport in the vertical direction.
KW - Crystallinity
KW - P3HT and PCBM
KW - Planar-heterojunction
KW - Polymer solar cells
KW - Surface morphology
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U2 - 10.1016/j.orgel.2011.08.011
DO - 10.1016/j.orgel.2011.08.011
M3 - Article
AN - SCOPUS:80052699438
SN - 1566-1199
VL - 12
SP - 1963
EP - 1972
JO - Organic Electronics: physics, materials, applications
JF - Organic Electronics: physics, materials, applications
IS - 11
ER -