Design of ultrathin CoAl-LDHs/ZnIn2S4 with strong interfacial bonding and rich oxygen vacancies for highly efficient hydrogen evolution activity

• Published in: Journal of colloid and interface science Vol. 651; pp. 138 - 148
• Main Authors: He, Zetian, Qian, Che, Chen, Daimei, Xu, Kang, Hao, Weichang
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.12.2023
• Subjects: CoAl-LDHs; Nanosheets; Oxygen vacancies; Photocatalytic hydrogen evolution; ZnIn2S4; CoAl-LDHs; Nanosheets; Oxygen vacancies; Photocatalytic hydrogen evolution; ZnIn2S4
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2023.07.179

[Display omitted] Designing a semiconductor-based heterostructure photocatalyst is very important way to enhance the hydrogen production activity. Here, a novel 2D/2D CoAl-LDHs/ZnIn2S4 S-scheme heterostructure with an ultrathin structure was synthesized by electrostatic attraction between CoAl-LDHs and ZnIn2S4 nanosheets. The presence of oxygen vacancies in the monolayer CoAl-LDHs nanosheet promotes the formation of Co-SX bonds, which serve as charge transfer channels at the interface of the CoAl-LDHs/ZnIn2S4 heterostructure. The ultrathin CoAl-LDHs/ZnIn2S4 exhibits broadened light absorption in the near-infrared range due to the occurrence of Co-SX chemical bonds. The CoAl-LDHs/ZnIn2S4 with a mass ratio of 1:2 demonstrated the highest photocatalytic hydrogen evolution activity (1563.64 μmol g−1 h−1) under the simulated sunlight, which is 4.6 and 9.7 times than that of the ZnIn2S4 and CoAl-LDHs/ZnIn2S4(bulk), respectively. The enhanced photocatalytic activity of ultrathin 2D/2D CoAl-LDHs/ZnIn2S4 should attributed to the shorter carriers path that benefit from the ultrathin structure and the quicker photogenerated charge transfer and the S-scheme migration pathway accelerated by the charge channel of Co-SX bonds. These new ideas should be inspiring for the design and construction of heterostructures for higher photocatalytic hydrogen evolution activity.