Theoretical Insight into High-Efficiency Triple-Junction Tandem Solar Cells via the Band Engineering of Antimony Chalcogenides
Theoretical Insight into High-Efficiency Triple-Junction Tandem Solar Cells via the Band Engineering of Antimony Chalcogenides
复制标题
通过锑硫属化物的能带工程对高效三结串联太阳能电池的理论见解
DOI：
10.1002/solr.202000800
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发表时间：
2021-02-26
期刊：
影响因子：
7.9
通讯作者：
Cuniberti, Gianaurelio
中科院分区：
文献类型：
--
作者：
Cao, Yu;Liu, Chaoying;Cuniberti, Gianaurelio
锑硫族化合物是一类很有前途的高效太阳能电池光电材料。迄今为止，基于单个硒化锑或硫化物的单结太阳能电池占主导地位，并且显示出有限的光电转换效率。因此，对于多结太阳能电池来说，仍然存在很大的差距。在此，通过Sb 2S 3/Sb-2（S0.7Se0.3）（3）/Sb 2Se 3堆叠的能带工程策略，设计并优化了三结锑硫属化合物基太阳能电池，理论效率为32.98%。中间电池的最佳Se含量应保持较低，即，30%，以实现吸收体层中的低缺陷密度。因此，基于Sb-2（S0.7Se0.3）（3）的中间太阳能电池通过充分利用太阳光谱而有助于提高三结器件中的外量子效率。在单结太阳能电池中，通过沿着Sb-2（S1-xSex）（3）的深度分布的Se含量梯度沿着来调节带隙梯度。此外，增加的Se含量分布提供了用于促进空穴载流子收集的额外的内建电场。因此，与传统电池相比，高电荷载流子产生速率导致转换效率提高17.96%。这项工作可能为将锑硫族化合物太阳能电池的转换效率提高到理论极限铺平道路。
Antimony chalcogenides have become a family of promising photoelectric materials for high-efficiency solar cells. To date, single-junction solar cells based on individual antimony selenide or sulfide are dominant and show limited photoelectric conversion efficiency. Therefore, great gaps remain for the multiple junction solar cells. Herein, triple-junction antimony chalcogenides-based solar cells are designed and optimized with a theoretical efficiency of 32.98% through band engineering strategies with Sb2S3/Sb-2(S0.7Se0.3)(3)/Sb2Se3 stacking. The optimum Se content of the mid-cell should be maintained low, i.e., 30% for achieving a low defect density in an absorber layer. Therefore, Sb-2(S0.7Se0.3)(3)-based mid solar cells have contributed to elevate the external quantum efficiency in triple-junction devices by the full utilization of the solar spectrum. In a single-junction solar cell, the bandgap gradient is regulated through the Se content gradient along the depth profile of Sb-2(S1-xSex)(3). Besides, an increasing Se content profile provides an additional built-in electric field for boosting hole charge carrier collection. Thus, the high charge carrier generation rate leads to a 17.96% improvement in the conversion efficiency compared with a conventional cell. This work may pave the way to boost the conversion efficiency of antimony chalcogenides-based solar cells to their theoretical limits.