Sulfur vacancy-rich ZnIn2S4 nanosheet arrays for visible-light-driven water splitting. (1st June 2022)

• Record Type: Journal Article
• Authors: Chen, Jie; Li, Kun; Cai, Xiaoyan; Zhao, Yulong; Gu, Xiuquan; Mao, Liang
• Is Part Of: Materials science in semiconductor processing. Volume 143(2022)
• Publication Date: 2022-06-01
• Subjects: ZnIn2S4 -- S vacancy -- Carrier density -- Hydrogen evolution; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2022.106547
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: In this study, ZnIn2 S4 nanosheet arrays (NSAs) were synthesized on transparent conductive F doped SnO2 (FTO) substrates via a facile hydrothermal method. S vacancies were introduced on the ZnIn2 S4 surface by a H2 –Ar plasma treatment. The sulfur vacancies were identified clearly by electron paramagnetic resonance (EPR). Under different plasma powers, the S vacancies concentration can be adjusted. With increasing the plasma power, both the photocurrent and H2 evolution rate of ZnIn2 S4 were increased. Through a 60 W plasma treatment, ZnIn2 S4 displayed a photocurrent density of 0.3 mAcm −2 at 0.3 VRHE, which was roughly 2 times higher than that of untreated ZnIn2 S4 . Correspondingly, the H2 evolution rate was 2.74 μmol cm −2 h −1 for ZnIn2 S4 NSA, in contrast to that of 0.96 μmol cm −2 h −1 for pristine ZnIn2 S4 NSA. The enhanced PEC performance was attributed to the enhancements of both the visible light absorption and carrier separation. Moreover, the S vacancies also acted as traps to retard the electron-hole recombination. This work provides a novel strategy for enhancing its PEC hydrogen evolution. Highlights: ZnIn2 S4 nanosheet arrays (NSAs) were synthesized through the hydrothermal method. The S vacancies were introduced into ZnIn2 S4 lattice by H2 /Ar plasma treatment. The S vacancy acted as an electron trap, suppressing the recombination of electrons and holes. Under an optimal plasma power, the ZnIn2 S4 NSA demonstrated a higher photocurrent and H2 evolution velocity than pure ZnIn2 S4 .