BiVO4@ZnIn2S4/Ti3C2 MXene quantum dots assembly all-solid-state direct Z-Scheme photocatalysts for efficient visible-light-driven overall water splitting. (September 2020)

• Record Type: Journal Article
• Authors: Du, Xin; Zhao, Tianyu; Xiu, Ziyuan; Xing, Zipeng; Li, Zhenzi; Pan, Kai; Yang, Shilin; Zhou, Wei
• Is Part Of: Applied materials today. Volume 20(2020)
• Publication Date: 2020-09
• Subjects: Photocatalysis -- Overall water splitting -- Direct Z-scheme system -- Hierarchical core-shell structure -- Assembly; Materials science -- Periodicals; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1016/j.apmt.2020.100719
• Languages: English
• ISSNs: 2352-9407

Abstract

Highlights: A novel BiVO4 @ZnIn2 S4 /Ti3 C2 MXene QDs photocatalyst is fabricated. All-solid-state direct Z-scheme charge transport system is proposed. Hierarchical core-shell structure offers adequate surface active sites. It exhibits excellent visible-light-driven photocatalytic performance. The co-catalysts of Ti3 C2 MXene QDs promote the spatial charge separation. Abstract: Novel BiVO4 @ZnIn2 S4 /Ti3 C2 MXene quantum dots (QDs) assembly all-solid-state direct Z-scheme photocatalyst is fabricated via in-situ growth combined with two-step solvothermal strategy, which forms a hierarchical core-shell structure. The proper energy band structure of BiVO4 and ZnIn2 S4 and the formation of a good solid-solid contact interface between them promote the construction of Z-scheme system, which achieves effective charge separation. It is surprisingly discovered that Ti3 C2 MXene QDs can be applied as cocatalysts for photocatalytic overall water splitting, which could accelerate the surface redox kinetics of the catalyst due to the unique properties of Ti3 C2 MXene QDs. In particular, due to its excellent metal conductivity, a Schottky barrier can be formed at the interface in contact with ZnIn2 S4, further promoting charge separation. BiVO4 @ZnIn2 S4 /Ti3 C2 MXene QDs achieves effective visible-light-driven pure water splitting into O2 and H2 evolution rates up to 50.83 and 102.67 μmol g −1 h −1 (~1:2). In addition, it also shows high photocatalytic degradation Bisphenol A efficiency of ~96.4 %. The high photocatalytic performance can be ascribed to the all-solid-state direct Z-scheme structure favoring spatial charge separation, Ti3 C2 MXene QDs as cocatalysts promoting proton reduction, and hierarchical core-shell structure offering more surface active sites. This work provides new insights to fabricate high-performance direct Z-scheme assembly system. Graphical abstract: Image, graphical abstract