. 2020 Aug 25;8:669. doi: 10.3389/fchem.2020.00669
Copyright © 2020 Li, Jiang, Wang, Chu and Du.
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Figure 3.
High-resolution XPS spectra of (A) Cu 2p, (B) Zn 2p, (C) In 3d, and (D) S 2p.