A Z-scheme photocatalyst for enhanced photocatalytic H2 evolution, constructed by growth of 2D plasmonic MoO3-x nanoplates onto 2D g-C3N4 nanosheets

Yanzhen Guo; Binbin Chang; Ting Wen; Shouren Zhang; Min Zeng; Nantao Hu; Yanjie Su; Zhi Yang; Baocheng Yang

doi:10.1016/j.jcis.2020.01.090

A Z-scheme photocatalyst for enhanced photocatalytic H₂ evolution, constructed by growth of 2D plasmonic MoO_3-x nanoplates onto 2D g-C₃N₄ nanosheets

J Colloid Interface Sci. 2020 May 1:567:213-223. doi: 10.1016/j.jcis.2020.01.090. Epub 2020 Jan 24.

Authors

Yanzhen Guo¹, Binbin Chang², Ting Wen², Shouren Zhang², Min Zeng¹, Nantao Hu¹, Yanjie Su¹, Zhi Yang³, Baocheng Yang⁴

Affiliations

¹ Key Laboratory of Thin Film and Microfabrication (Ministry of Education), Department of Micro/Nano Electronics, School of Electronic Information and Electrical Engineering, Center of Hydrogen Science, Shanghai Jiao Tong University, Shanghai 200240, China.
² Henan Provincial Key Laboratory of Nanocomposites and Applications, Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou 450006, China.
³ Key Laboratory of Thin Film and Microfabrication (Ministry of Education), Department of Micro/Nano Electronics, School of Electronic Information and Electrical Engineering, Center of Hydrogen Science, Shanghai Jiao Tong University, Shanghai 200240, China. Electronic address: zhiyang@sjtu.edu.cn.
⁴ Henan Provincial Key Laboratory of Nanocomposites and Applications, Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou 450006, China. Electronic address: baochengyang@infm.hhstu.edu.cn.

PMID: 32058171
DOI: 10.1016/j.jcis.2020.01.090

Abstract

Light-harvesting capacity and photoexcited charge carrier separation ability are two crucial requirements for high-efficiency semiconductor photocatalysis. Here, we report a plasmonic Z-scheme nanohybrid by hydrothermally in-situ growing two-dimensional (2D) oxygen-deficient molybdenum oxide (MoO_3-x) nanoplates onto 2D graphitic carbon nitride (g-C₃N₄) nanosheets. The resultant 2D/2D MoO_3-x/g-C₃N₄ nanohybrids not only construct a unique Z-scheme heterojunction, which improves the photogenerated charge carrier separation efficiency, but also possess numerous oxygen vacancies on the surface of MoO_3-x, which could excite its plasmon resonance for extending spectrum adsorption. Importantly, the plasmon resonance can be readily designed by tailoring the oxygen vacancy concentration via an annealing in air. Benefiting from the synergetic effect of interfacial Z-scheme heterojunction and the tunable plasmon resonance of MoO_3-x, the as-obtained nanohybrids achieve a remarkably improved photocatalytic H₂ evolution efficiency. The optimal Z-scheme heterostructure presents 2.6 and 1.7 times higher of H₂ evolution rate as compared to pure g-C₃N₄ and the annealing nanohybrid under visible light irradiation. Even under light irradiation with wavelength longer than 590 nm, the hybrid photocatalyst displays a H₂ generation rate as high as 22.8 µmol h^-1 due to the plasmonic sensitization effect. The result in our work can provide an alternative for fabricating Z-scheme heterostructures that take advantages of Z-scheme-induced charge carrier separation, accompanied with plasmon-enhanced light harvesting of semiconductor to advance the solar energy conversion efficiency in photocatalysis.

Keywords: 2D/2D heterostructure; H(2) evolution; Plasmonic MoO(3-x) semiconductor; Z-scheme heterojunction; g-C(3)N(4).