Abstract Correlation between Urbach energy (EU) and open-circuit voltage deficit (VOC,def) among conventional as well as emerging thin-film solar cells, i.e. Cu(In,Ga)Se2 (CIGSe), Cu(In,Ga)(S,Se)2 (CIGSSe), Cu2SnS3 (CTS), Cu2Sn1-xGexS3 (CTGS), SnS, Cu2ZnSnSxSe4-x (CZTSSe), perovskite (PVK), Cu(In,Ga)S2 (CIGS), and CdTe thin-film solar cells, is examined. The EU is estimated from an exponential tail in a long-wavelength edge of an external quantum efficiency. It is determined that the relation between short-circuit current density (JSC) and EU is not clearly shown because the JSC is primarily influenced by the bandgap of the thin-film absorbers. On the other hand, EU demonstrates a close relation with VOC,def, where the reduction of the EU leads to the decrease in the VOC,def, implying that the EU can be used as an indicator of the absorber quality. The EU of over 20 meV, observed in the CIGS, CTS, CTGS, SnS, and CZTSSe solar cells, gives rise to the high VOC,def and the low conversion efficiency (η) values. The EU of below 20 meV, seen in the CIGSe, CIGSSe, PVK, and CdTe solar cells, leads to the low VOC,def and high η values. Ultimately, the thin-film absorbers with the EU values of below 20 meV, which is lower than thermal energy under room temperature, is of vital to realize high photovoltaic performances.

中文翻译：

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Urbach能量对薄膜太阳能电池开路电压不足的影响

摘要 传统和新兴薄膜太阳能电池即 Cu(In,Ga)Se2 (CIGSe)、Cu(In,Ga)() 之间的 Urbach 能量 (EU) 与开路电压赤字 (VOC,def) 之间的相关性S,Se)2 (CIGSSe)、Cu2SnS3 (CTS)、Cu2Sn1-xGexS3 (CTGS)、SnS、Cu2ZnSnSxSe4-x (CZTSSe)、钙钛矿 (PVK)、Cu(In,Ga)S2 (CIGS) 和 CdTe薄膜太阳能电池，进行了检查。EU 是从外部量子效率的长波长边缘的指数尾部估计的。确定短路电流密度 (JSC) 和 EU 之间的关系没有明确显示，因为 JSC 主要受薄膜吸收体的带隙影响。另一方面，EU表现出与VOC,def的密切关系，其中EU的减少导致VOC,def的降低，暗示EU可以作为吸收体质量的指标。在 CIGS、CTS、CTGS、SnS 和 CZTSSe 太阳能电池中观察到的超过 20 meV 的 EU 导致高 VOC,def 和低转换效率 (η) 值。在 CIGSe、CIGSSe、PVK 和 CdTe 太阳能电池中看到的 EU 低于 20 meV，导致低 VOC,def 和高 η 值。最终，EU值低于20 meV的薄膜吸收器，低于室温下的热能，对于实现高光伏性能至关重要。