Abstract
Despite the potential as a promising alternative to CdTe and Cu(In,Ga)Se2, the kesterite compound Cu2ZnSn(S,Se)4 (CZTSSe) presents a critical challenge mainly from its high open-circuit voltage (Voc) deficit. Indeed, the Voc of the record CZTSSe solar cell to date has accounted for only 61% of that calculated by the Shockley–Queisser limit, whose origin can be ascribed to nonradiative recombination from a high density of defects and secondary phases. Therefore, an atomistic understanding and characterization of CZTSSe is highly essential to overcoming the current shortcomings in kesterite. This review discusses the advanced characterization techniques for studying the intrinsic properties of kesterite at a nanometer scale. Moreover, a cation substitution with an ionic mismatch around constituents is recognized as an effective route to address the fundamental limit (i.e., the cationic disorder) in CZTSSe. Here, we review recent studies on a novel chalcogenide Cu2BaSn(S,Se)4 that substitutes Zn with Ba and results in less cationic disordering.
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ACKNOWLEDGMENTS
This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (Nos. 20163030013690 and 20173010012980), by the Technology Development Program to Solve Climate Changes (No. 2016M1A2A2936757) and Brain Pool Program (Grant No. 2018 H1D3A2002475) of the National Research Foundation (NRF) funded by the Ministry of Science and ICT. This research was also financially supported by the Framework of the Research and Development Program of the Korea Institute of Energy Research (KIER) (Grant No. B8-2421).
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Kim, J., Larina, L., Chung, SY. et al. Atomistic consideration of earth-abundant chalcogenide materials for photovoltaics: Kesterite and beyond. Journal of Materials Research 33, 3986–3998 (2018). https://doi.org/10.1557/jmr.2018.350
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DOI: https://doi.org/10.1557/jmr.2018.350