Fang Junfei, Lv Wenlei, Lei Yilong, Deng Jianping, Zhang Pengchao, Huang Wendeng
Shaanxi Key Laboratory of Industrial Automation, School of Mechanical Engineering, Shaanxi University of Technology, Hanzhong 723001, China.
School of Physics and Telecommunications Engineering, Shaanxi University of Technology, Hanzhong 723001, China.
Dalton Trans. 2021 Oct 26;50(41):14672-14683. doi: 10.1039/d1dt02061g.
CdSSe alloy and CdS/CdSe core/shell quantum dots (QDs) are widely studied in quantum dot solar cells (QDSSCs). However, to date, there have been no detailed comparative investigations into the cell performance between CdSSe alloy and CdS/CdSe core/shell structures prepared with the same preparation process. In this work, the performances of CdSSe alloy and CdS/CdSe core/shell QDSSCs, which are prepared with the same SILAR (successive ionic layer adsorption and reactions) process, are investigated in detail. By simply tuning the layer numbers and arrangement sequence of the CdS and CdSe layers, a series of QDs, including CdSSe alloy structures, CdS/CdSe multilayer structures, and CdS/CdSe core/shell structures, are successfully prepared with a layer-by-layer technique, while maintaining a similar morphology. Based on these QD sensitized TiO photoanodes, QDSSCs are assembled. The CdS/CdSe core/shell QDSSCs yield a maximum power conversion efficiency of 5.08% under AM 1.5 illumination of 100 mW cm, which is increased by 77% in comparison with that of CdSSe alloy QDSSCs (2.87%). The significantly enhanced photovoltaic performance of QDSSCs with core/shell architectures is mainly attributed to their high short-circuit current density, which arises from the enhanced absorption intensity. In addition, the CdS/CdSe core-shell contributes to the attenuation of the interfacial charge recombination rate and prolongs the electron lifetime, resulting in more efficient charge collection in QDSSCs.
硫化镉硒合金和硫化镉/硒化镉核壳量子点（QDs）在量子点太阳能电池（QDSSCs）中得到了广泛研究。然而，迄今为止，尚未对采用相同制备工艺制备的硫化镉硒合金和硫化镉/硒化镉核壳结构之间的电池性能进行详细的比较研究。在这项工作中，详细研究了采用相同的连续离子层吸附和反应（SILAR）工艺制备的硫化镉硒合金和硫化镉/硒化镉核壳QDSSCs的性能。通过简单地调整硫化镉和硒化镉层的层数和排列顺序，采用逐层技术成功制备了一系列量子点，包括硫化镉硒合金结构、硫化镉/硒化镉多层结构和硫化镉/硒化镉核壳结构，同时保持了相似的形貌。基于这些量子点敏化的二氧化钛光阳极，组装了QDSSCs。在100 mW/cm²的AM 1.5光照下，硫化镉/硒化镉核壳QDSSCs的最大功率转换效率达到5.08%，与硫化镉硒合金QDSSCs（2.87%）相比提高了77%。具有核壳结构的QDSSCs显著增强的光伏性能主要归因于其高短路电流密度，这源于增强的吸收强度。此外，硫化镉/硒化镉核壳有助于降低界面电荷复合率并延长电子寿命，从而在QDSSCs中实现更有效的电荷收集。
