Photovoltaic Properties of Star Polymer and Fullerene Blends
Abstract
The photovoltaic properties of star polymers with polyethylenedioxythiophene-didodecyloxybenzene arms (SPEB) are significantly improved with [6,6]-phenyl C_61-propionic acid methyl ester (PCPM) as the electron acceptor (1:2 SPEB:PCPM). Devices utilize a Baytron-P over indium tin oxide cathode and an aluminum anode. The short circuit current dependence on light intensity exhibits a nearly linear response over 4 decades of light intensity. This indicates the incident photon conversion efficiency (IPCE) remains constant over the intensity range with a value of 5% at the peak of the polymer absorption. The external power conversion efficiency is 0.1Global illumination. The open circuit voltage is 0.44 V and the short circuit current is 0.7 mA/cm^2 with a 0.32 fill factor under AM1.5 Global illumination. Devices with C_60 as the electron acceptor have significantly lower power efficiency and short circuit current. The short circuit current dependence on light intensity is sub-linear, indicating the IPCE decreases with increasing light intensity. This is most likely due to poor charge transport within the C_60 network.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2003
- Bibcode:
- 2003APS..MARY16014F