Abstract
Heterojunction interfacial engineering plays a crucial role for the CIGS efficiency promotion. Chemical bath deposition (CBD) prepared CdS is the most preferred buffer for CIGS solar cells. Hence, manipulating the CdS properties to further boost heterojunction quality is a promising way to achieve higher efficiency CIGS solar cells. In this work, CdS buffer layer was modified by (NH4)2S (AS-treatment) solutions. The results showed that after AS treatment, the impurities on CdS film were cleaned and the S vacancy was passivated. Moreover, it introduced larger build-in electric field, wider depletion width and less interface defect densities, which contributed to suppressed interface recombination and more efficient carrier separation and collection. Consequently, the CIGS solar cell based on AS-treatment achieved champion efficiency of 15.52%, with improved VOC of 643 mV and FF of 73.3%.
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Funding
This study is supported by scientific Research Foundation from North China University of Water Resources and Electric Power (Grant No. 4001/40510), the National Natural. Science Foundation of China (Grant Nos. 51802081, 62074052, 61974173, 62104061 and 52072327).
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The manuscript was written through contribution of all authors. All authors have approval to the final version of the manuscript. XW: experiments, characterization, writing—original draft. YL: discussion, EQE measurement. QG: discussion, EIS measurement. JK: data analyses, discussion and review. SY: supervision, discussion, writing—review & editing. SW: discussion and data analyses.
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Wang, X., Li, Y., Gao, Q. et al. (NH4)2S-induced improvement of CdS buffer layer for 15.52% efficiency solution-processed CIGS solar cell. J Mater Sci: Mater Electron 34, 1680 (2023). https://doi.org/10.1007/s10854-023-11097-z
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DOI: https://doi.org/10.1007/s10854-023-11097-z