Effects of bifunctional linker on the performance of P3HT/CdSe quantum dot-linker-ZnO nanocolumn photovoltaic device.

We study the effects of bifunctional linker on the photovoltaic properties of P3HT/CdSe quantum dot-linker-ZnO nanocolumn heterostructure. The CdSe quantum dots are bound on the surface of ZnO nanocolumns through either aliphatic linker of 3-aminopropyl trimethoxysilane(APS) or aromatic linker of p-aminophenyl trimethoxysilane(APhS) using simple solution process. As compared to CdSe bound by aliphatic linker(APS), while CdSe is bound by aromatic linker(APhS), more than one fold increase of short circuit current density (J(SC)) of the device obtained under irradiance, which is attributed to a more efficient charge transfer dynamics at interface. In addition, the ZnO-APhS-CdSe/P3HT devices possess about 4.8 folds in power conversion efficiency as compared to ZnO/P3HT device as the results of reduction in shunt loss and interfacial recombination.