It has been proven that both recombination and band gap difference are the key issues responsible for V_oc enhancement, and a wide band gap inorganic hole-transporting material (HTM) is more favorable for efficient perovskite solar cells. Herein, we employed the wide band gap CuGaS₂ (CGS) quantum dots (QDs) as HTM. And such quantum dots were used in novel solar cells based on perovskite materials though the method of cation substitution. Through substitution of indium element with gallium element, band gap of the QDs was changed greatly (from 1.56 eV to 2.29 eV). The processes of charge transfer and the alignment of band level were studied in details and the result indicates that the increase of conduction band level for CGS with wide band gap led to a dramatic increase in V_oc. And the cell efficiency was finally improved from 10.46% to 12.78%.

已经证明，复合和带隙差异都是导致V _oc增强的关键问题，宽带隙无机空穴传输材料 (HTM) 更有利于高效钙钛矿太阳能电池。在此，我们采用宽带隙 CuGaS ₂(CGS) 量子点 (QD) 作为 HTM。并且这种量子点通过阳离子取代的方法被用于基于钙钛矿材料的新型太阳能电池中。通过用镓元素取代铟元素，量子点的带隙发生了很大变化（从 1.56 eV 到 2.29 eV）。详细研究了电荷转移过程和能带能级的排列，结果表明，对于宽禁带的CGS，导带能级的增加导致V _oc的急剧增加。电池效率最终从10.46%提高到12.78%。