Fabrications of three copper sulfide counter electrodes and their influences on photovoltaic properties in QDSSCs
- 2016年第22卷 
近几年，量子点敏化太阳能电池因其具有低成本、易合成、高的光电转换效率等优点而广受关注. 半导体金属硫化物具有良好的物理和化学性质，被广泛应用于各个领域，其中，铜硫化物凭借其优异的电化学催化活性，而成为量子点敏化太阳能电池良好的对电极材料. 本文通过3种不同的方法在FTO表面生长CuS纳米阵列（依次记为CuS-1、CuS-2、CuS-3），并对样品进行晶相表征、表面形貌分析、电化学性能测试以及相应量子点敏化太阳能电池器件组装，最终发现CuS-3样品具有最优的光电性能.Quantum dot-sensitized solar cells (QDSSCs) have attracted intensive attention in scientific and industrial fields due to their high molar extinction coefficient, spectral tunability by particle size, ease of fabrication, and low cost. In the past years, semiconductor metal sulfides have attracted extensive attention because of their attractive physical and chemical properties for potential applications in many fields，such as PbS, CuS, CoS and CdS. In particular, copper sulfides have become a promising candidate for counter electrode materials in QDSSCs for their outstanding electrochemical and catalytic properties. In order to explore more stable and efficient copper sulfide counter electrode materials, in this work, we used three different methods to synthesize copper sulfide nanosheet arrays (marked as CuS-1, CuS-2, CuS-3), which were then characterized by XRD, SEM and electrochemical workstation. XRD patterns showed that all the three samples were copper sulfide (Cu:S = 1:1). And SEM images revealed that the fabrication methods of CuS significantly affected their morphologies. . The obtained CuS-1, CuS-2 and CuS-3 nanosheet arrays exhibited enhanced PCEs up to 2.92%，2.58% and 3.27%, respectively, when used as CEs in QDSSCs, implying increases of 87%，65% and 109% as compared to Pt-based QDSSCs, respectively. Through all the characterizations, we found that the CuS-3 showed the best catalytic activity in the reduction of polysulfide electrolyte among the three samples.