Rational Design of Heterojunction Interface for Cu2ZnSn(S,Se)4 Solar Cells to Exceed 12% Efficiency
Rational Design of Heterojunction Interface for Cu2ZnSn(S,Se)4 Solar Cells to Exceed 12% Efficiency
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Rational%20Design%20of%20异质结%20Interface%20for%20Cu2ZnSn(S,Se)4%20Solar%20Cells%20to%20Exceed%2012%%20效率
DOI：
10.1002/solr.202101032
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发表时间：
2022
期刊：
影响因子：
7.9
通讯作者：
S. Liu
中科院分区：
文献类型：
--
作者：
Junjie Fu;Qingwen Tian;Yachao Du;Qianqian Chang;Yanping Guo;Shengjie Yuan;Z. Zheng;Sixin Wu;S. Liu
锌黄锡矿Cu 2 ZnSn（S，Se）4太阳能电池的光伏性能仍远低于其前身CuInGaSe 2。一个主要原因是其在失配的Cu 2 ZnSn（S，Se）4/CdS异质结界面处的严重界面非辐射复合，导致大的开路电压损耗。本文中，开发了独特的铟掺入（DI）策略来存款In 1 −xCdxS缓冲层以优化异质结界面。结果表明，采用这种DI方法可以有效地抑制不期望的第二相的形成，并且铟可以更容易地掺杂到CdS的体晶格中，形成额外的有益的浅施主InCd缺陷，这显著改善了CdS层的电学性能和异质结界面的质量。此外，通过调整能带的排列方式，有利于界面电荷的提取和转移，从而减少了Cu 2 ZnSn（S，Se）4/CdS异质结前界面的非辐射电荷复合.因此，上述的组合将功率转换效率从10.2%提高到12.4%，这是这种类型电池的最高效率之一，这对应于开路电压差（Voc，def）降低到低至0.54 V。该策略为优化Cu 2 ZnSn（S，Se）4太阳电池的异质结界面提供了一种合理的设计方法，从而降低了电池的电压损耗，提高了电池的效率。
The photovoltaic performance of the kesterite Cu2ZnSn(S,Se)4 solar cells is still far below its predecessor CuInGaSe2. One major reason is its severe interface nonradiative recombination at the mismatched Cu2ZnSn(S,Se)4/CdS heterojunction interface, leading to a large open‐circuit voltage loss. Herein, a distinctive indium‐incorporation (DI) strategy is developed to deposit an In1−xCdxS buffer layer for optimizing the heterojunction interface. The results reveal that adopting this DI method can effectively inhibit the formation of an undesirable secondary phase, and indium can be more easily doped into the bulk lattice of CdS to form additional beneficial shallow donor InCd defects, which significantly improve the electrical properties of the CdS layer and the quality of the heterojunction interface. Besides, the energy band alignment is adjusted to facilitate the extraction and transfer of interfacial charges, and thus reducing the nonradiative charge recombination at the front Cu2ZnSn(S,Se)4/CdS heterojunction interface. Consequently, the combination of the above enhances the power conversion efficiency from 10.2% to 12.4%, one of the highest for this type of cells, which corresponds to an open‐circuit voltage deficit (Voc,def) reduction to as low as 0.54 V. The strategy provides a rational design for optimizing the heterojunction interface of Cu2ZnSn(S,Se)4 solar cells to reduce voltage loss and achieve high efficiency.