Enhancing the efficiency of Cu2ZnSn (S, Se)4 (CZTSSe) thin‐film solar cells requires the development of well‐crystallized light‐absorbing layers. A deep understanding of the role of precursor solution chemistry in film nucleation and crystal growth processes is essential. Insights into these processes enable the development of innovative strategies to enhance absorber quality, minimize detrimental bulk defects, and ultimately improve device performance. This study elucidates the condensation reactions between thiourea and metal cations, as well as the alcoholysis of 2‐methoxyethanol (MOE), at different concentrations of precursor solutions. The primary focus of this study is implementing a simple and environmentally friendly innovative spin‐coating strategy, aimed at optimizing Cu2ZnSnS4 (CZTS) precursor films and adjusting the Se content within the film bulk to promote grain growth during selenization. This strategy effectively improves absorber morphology while suppressing the formation of deep‐level defects, thereby enhancing carrier transport in both interfacial and bulk regions of the absorber layer. Consequently, CZTSSe absorbers with enhanced crystallinity and reduced defects are synthesized, resulting in a solar cell with an impressive efficiency of 14.10%. These findings underscore the potential for creating highly efficient kesterite CZTSSe solar cells through the manipulation of precursor solution chemistry using environmentally friendly solvents.

中文翻译：

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一种面向高效太阳能电池的 Cu2ZnSn（S， Se）4 薄膜开发前驱体求解策略


提高 Cu2ZnSn （S， Se）4 （CZTSSe） 薄膜太阳能电池的效率需要开发结晶良好的光吸收层。深入了解前驱体溶液化学在薄膜成核和晶体生长过程中的作用至关重要。深入了解这些过程有助于制定创新策略，以提高吸收器质量，最大限度地减少有害的散装缺陷，并最终提高器件性能。本研究阐明了硫脲和金属阳离子之间的缩合反应，以及 2-甲氧基乙醇 （MOE） 在不同浓度的前驱体溶液下的醇解。本研究的主要重点是实施一种简单且环保的创新旋涂策略，旨在优化 Cu2ZnSnS4 （CZTS） 前驱体薄膜并调整薄膜块内的 Se 含量，以促进硒化过程中的晶粒生长。这种策略有效地改善了吸收体形态，同时抑制了深层缺陷的形成，从而增强了吸收层界面和体体区域的载流子传输。因此，合成了结晶度更高、缺陷更少的 CZTSSe 吸收剂，从而产生了具有令人印象深刻的 14.10% 效率的太阳能电池。这些发现强调了通过使用环保溶剂操纵前驱体溶液化学来制造高效 kesterite CZTSSe 太阳能电池的潜力。