A trilayer architecture for polymer photoconductors

A trilayer architecture is designed for polymer photoconductors. In such a structure, photogenerated electrons in poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid ethyl ester (P3HT:PCBM) blend film will flow into a TiOx layer beneath and then diffuse into a underlying PCBM layer. Photogenerated holes and electrons are thus efficiently separated by the spacer TiOx, and, respectively, transport in P3HT and PCBM films, carrier recombination is thereby greatly suppressed. As a result, photocurrent of the PCBM/TiOx/P3HT: PCBM trilayer structure increases more than 200 times over that of the conventional P3HT: PCBM single layer device. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4791595]