Construction of CdS@g–C3N4 heterojunction photocatalyst for highly efficient degradation of gaseous toluene

Abstract

Exploring efficient photocatalysts for the degradation of VOCs under visible light is a challenge. CdS@g–C3N4 heterojunction photocatalytic materials were developed in this study using a microwave-assisted sol-gel process. CdS@g–C3N4(0.2) photocatalyzed the maximum degradation of gaseous toluene under visible light irradiation, and the time required to achieve the same degradation rate was reduced by 270 min when compared to pure CdS. The morphological characterization, photoelectric property analysis, and DFT calculations all verified that the CdS nanoparticles were uniformly disseminated on the surface of g–C3N4, and that the interfaces were closely contacted to form a heterojunction interface with a built-in field. This enhances charge transfer from CdS to g–C3N4 while successfully decreasing electron-hole pair recombination caused by light. Furthermore, the energy band structure was altered to absorb longer wavelengths of light and extend the absorption spectral range, improving the photocatalytic material's efficacy for broad-spectrum light such as sunshine. This paper proposes methods for predicting and optimizing the surface structure of catalysts, as well as developing high-performance multi-heterojunction photocatalysts for the degradation of indoor VOCs.