In-Situ Construction of 2D/2D ZnIn₂S₄/BiOCl Heterostructure with Enhanced Photocatalytic Activity for N₂ Fixation and Phenol Degradation

Abstract

Photocatalytic nitrogen fixation and pollutants degradation at ambient temperature and pressure as a clean and efficient means represents a sustainable direction. In this paper, novel two-dimensional (2D) ZnIn2S4/2D BiOCl (ZIS/BOC) nanosheets heterostructures were successfully synthesized by in-situ solvothermal techniques. XPS and TEM results showed the formation of heterostructure. The photocatalytic properties of these materials were further studied by degradating phenol and nitrogen fixation under visible light irradiation. In particular, heterostructure obtained with a mass ratio of 0.5 wt % of ZnIn2S4 had a good application prospect and can achieve 77.4% phenol degradation rate within 6 h and a rate of ammonium production of 14.6 µmol∙gcat−1·h−1. The reaction rate of 0.5 wt % ZIS/BOC heterostructure exhibited 8.6 and 2.6 times relative to BiOCl for the degradation of phenol and nitrogen fixation, respectively. The enhanced photocatalytic activity was attributed to the collaboration of low recombination rate of photo-generated carriers and enhanced visible light absorption. Based on capture experiments and electron spin resonance (ESR) techniques, the main active species that may appear in photocatalytic systems were explored, and the corresponding photocatalytic mechanism was also proposed appropriately. This strategy will open up new ideas for the design and manufacture of more energy-efficient materials with high photocatalytic activity.

Keywords

• in-situ assembly
• ZnIn₂S₄/BiOCl 2D/2D heterostructure
• phenol degradation
• nitrogen fixation