Liquid junction quantum dot solar cells based on ZnO nanowires arrays

摘要

Liquid junction solar cells sensitized with quantum dots are promising structures as low cost and high efficiency photovoltaic devices. However, the reported short circuit current and open circuit voltage is lower than the theoretical values. The performance of these cells can be improved by the use of defect-free photoelectrodes and absorbing materials. In this work, hydrothermally grown zinc oxide (ZnO) nanowires (NWs), CdSe/ZnS quantum dots (QDs), a polysulfide solution and a cupper film were used as the photoelectrode, light absorber, hole scavenger, and counter electrode respectively to form a NW-based QD sensitized solar cell. The structural characteristics of the grown NWs and QD sensitized NW architectures were studied. Current-voltage (J-V) characteristic of the fabricated device was also investigated. Photoluminescence (PL) study on NW/QD and QD/electrolyte architectures provided evidence on carrier transfer from the light absorbing centers to the electron and hole conducting media.