The earth‐abundant and environmentally‐friendly CuSbS₂ solar cells have been struggling with low device performance, especially poor open circuit voltage (V_oc). In this work, post‐annealing treatment of the CuSbS₂/CdS heterojunction performed on CuSbS₂‐based solar cells was firstly reported. With this treatment, we demonstrated CuSbS₂ solar cells with a record V_oc of 622 mV. The improvement of device performance was found peaked at 250°C post‐annealing which mainly benefits from the significantly boosted open‐circuit voltage and short‐circuit current. The study of microstructure by high‐resolution transmission electron microscopy revealed that such improvement could be attributed to the formation of epitaxial CuSbS₂/CdS hetero‐interface upon heat treatment, which reduces the interface defect density that may lead to reduced V_oc deficit. Besides, results of photoluminescence and time‐resolved photoluminescence measurements also indicated improved electrical properties of completed devices with higher photoluminescence intensity and longer minority carrier lifetime.

中文翻译：

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通过后退火处理形成CdS / CuSbS2异质界面的外延生长，实现了高开路电压CuSbS2太阳能电池

富含地球和环保的CuSbS ₂太阳能电池一直在努力降低设备性能，特别是开路电压（V _oc）较差。在这项工作中，首次报道了对基于CuSbS ₂的太阳能电池进行CuSbS ₂ / CdS异质结的退火后处理。通过这种处理，我们展示了具有创纪录V _oc的CuSbS ₂太阳能电池622 mV。发现器件性能的改善在退火后达到250°C达到峰值，这主要得益于明显提高的开路电压和短路电流。高分辨率透射电子显微镜对微观结构的研究表明，这种改善可以归因于热处理后形成的外延CuSbS ₂ / CdS异质界面，从而降低了界面缺陷密度，可能导致V _oc缺陷减少。此外，光致发光和时间分辨的光致发光测量结果还表明，具有更高的光致发光强度和更长的少数载流子寿命的完整器件的电气性能得到了改善。