Enhanced photovoltaic performance of copper phthalocyanine by incorporation of polyoxometalate

The improvement of the photoconversion efficiency has become a crucial issue for the utilization of organic semiconductors. Here we prepared a composite film of copper phthalocyanine (CuPc) and polyoxometalates (POMs) which displayed the enhanced photovoltaic performance. Especially, the photocurrent response and power conversion efficiency of CuPc/POMs composite film showed a 6-fold and a 10-fold increase, respectively, as compared to the single CuPc film. Based on the measurements of surface photovoltage technique, the enhanced photocurrent should be attributed to the occurrence of the photoinduced electron transfer between CuPc and POMs, which increases the dissociation of excited electron-hole pairs (excitons). Moreover, the CuPc/POMs composite film exhibited good photoelectrocatalytic performance for the oxidation of hydrazine. These results demonstrate that the incorporating of appropriate POMs into organic semiconductors is a promising route for developing and optimizing organic photovoltaic and photoelectrochemical devices. (c) 2012 Elsevier B.V. All rights reserved.