Reduced graphene oxide (RGO)/Cu2S composite as catalytic counter electrode for quantum dot-sensitized solar cells

For improving the counter electrodes (CEs) quality of quantum dot-sensitized solar cells (QDSSCs), reduced graphene oxide (RGO)/Cu2S composite material has been prepared by a facile solvothermal method. The photovoltaic and electrochemical properties of the RGO/Cu2S CEs are investigated in detail. Compared with bare Cu2S CEs, the QDSSCs based on RGO/Cu2S composite electrodes display an apparent improvement in cell performances, the photovoltaic conversion efficiency (PCE) has been enhanced 51%. The QDSSCs with RGO/Cu2S CEs yield a PCE of 4.76% with short circuit current density (Jsc) of 17.10 mA cm−2, open circuit voltage (Voc) of 0.58 V and fill factor (FF) of 0.48. Present work demonstrates RGO/Cu2S composite could be a potential material for CEs of QDSSCs because of its excellent electrical conductivity, better catalytic activity, higher stability and smaller charge transfer resistance.