Former studies have investigated the band structure and optoelectronic properties of Cu₃AsS₄ and suggested that it is a promising photovoltaic (PV) absorber. However, its power conversion efficiency (PCE) from experiments is still unsatisfactory and detailed experimental optimization strategies are lacking. Here, combining first-principles calculations and SCAPS-1D device simulations, we have systematically studied the optoelectronic and defect properties of Cu₃AsS₄ to find the suitable growth conditions and have performed various device simulations by adjusting the constituent layers to optimize the device configuration of the Cu₃AsS₄ solar cell. Our results demonstrated that the defect and hole concentrations can be regulated to a reasonable range as the PV absorber in metal-rich and S-poor growth environments with a low growth temperature of 500 K. Owing to the large cliff-like conduction band offset between the traditional buffer layers CdS and Cu₃AsS₄, the open-circuit voltage loss is large and the corresponding PCE is low. The PCE can be improved by adopting the new buffer layers with low electron affinity. The corresponding n-type transparent electrode is further optimized. Finally, the solar cell with the configuration of FTO/WO₃/Cu₃AsS₄/Mo is suggested and its PCE can reach an optimal value of 17.82%.

中文翻译：

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Cu3AsS4 太阳能电池制备条件优化和器件配置设计：第一性原理计算和 SCAPS-1D 器件仿真的结合研究


以前的研究调查了 Cu₃AsS₄ 的能带结构和光电性质，并表明它是一种很有前途的光伏 （PV） 吸收剂。然而，其实验的功率转换效率 （PCE） 仍然不令人满意，并且缺乏详细的实验优化策略。在这里，结合第一性原理计算和 SCAPS-1D 器件模拟，我们系统地研究了 Cu₃AsS₄ 的光电和缺陷特性，以找到合适的生长条件，并通过调整组成层进行了各种器件模拟，以优化 Cu₃AsS₄ 的器件配置太阳能电池。我们的结果表明，在生长温度为 500 K 的低金属和贫 S 生长环境中，作为 PV 吸收器，可以将缺陷和空穴浓度调节到合理的范围内。由于传统缓冲层 CdS 和 Cu₃AsS₄ 之间的大悬崖状导带偏移，开路电压损耗大，相应的 PCE 较低。通过采用低电子亲和力的新缓冲层，可以改善 PCE。相应的 n 型透明电极进一步优化。最后，提出了 FTO/WO₃/Cu₃AsS₄/Mo 配置的太阳能电池，其 PCE 可以达到 17.82% 的最佳值。