Synthesis of flexible CuxS-CNT/Ti counter electrodes for improved quantum dots sensitized solar cells

In this study, flexible CuxS-CNT/Ti counter electrodes (CEs) were prepared through successive ionic layer adsorption followed by reaction technique (SILAR). The electrocatalytic activities of the obtained CuxS-CNT/Ti CEs were investigated by electrochemical impedance spectroscopy (EIS) and Tafel polarization measurements. The results indicated that the catalytic activities of CNT/Ti films significantly improved after deposition of CuxS nanoparticles. CuxS-CNT/Ti flexible CEs were then assembled with CdS and CdSe QDs co-sensitized TiO2 film electrodes to prepare simple QDSCs. The optimized QDSCs based on CuxS-CNT/Ti flexible CEs delivered photovoltaic conversion efficiencies reaching ca. 6.20%. These values were ca. 48.7% higher than those based on CNT/Ti CEs.