Selenization is effective to fabricate high-efficiency kesterite Cu₂ZnSnSe₄ (CZTSe) solar cells that facilitates the composition modification, crystallization enhancement, and bandgap adjustment. The incorporation of Sb into CZTSe absorbers can further boost the device efficiency mainly due to promoting the grain growth of CZTSe absorber. Here we report a Sb₂Se₃ and Se co-selenization process that significantly improves the quality of CZTSe absorber layers. This strategy enables the increase of CZTSe grain size and elimination of pinholes. We find that Sb is uniformly distributed in the absorber layer. When the Sb/(Cu + Zn + Sn) ratio is tuned to 6.67‰, the CZTSe solar cell exhibits the best device performance with an efficiency up to 9.64%, over 40% higher than the traditional selenization process. Our work provides a new route for enhancing the device efficiency of CZTSe solar cells.

硒化有效地制造了高效率的方铅矿型Cu ₂ ZnSnSe ₄（CZTSe）太阳能电池，该电池有助于成分改性，结晶增强和带隙调节。在CZTSe吸收剂中掺入Sb可以进一步提高器件效率，这主要是由于促进了CZTSe吸收剂的晶粒长大。在这里我们报告Sb ₂ Se ₃和硒共硒化工艺，可显着提高CZTSe吸收层的质量。这种策略可以增加CZTSe晶粒尺寸并消除针孔。我们发现Sb均匀分布在吸收层中。当Sb /（Cu + Zn + Sn）比例调整为6.67‰时，CZTSe太阳能电池表现出最佳的器件性能，效率高达9.64％，比传统的硒化工艺高40％以上。我们的工作为提高CZTSe太阳能电池的器件效率提供了一条新途径。