Study on TiO2/g-C3N4 S-Scheme heterojunction photocatalyst for enhanced formaldehyde decomposition

Photocatalytic degradation of pollutants is one of the most environmentally friendly and energy efficient technologies. Photocatalysts with porous structures not only enhance the adsorption of pollutants by the catalyst, but also accelerate the electron transfer and enhance the photocatalytic performance due to the exposure of more active sites. In addition, the S-Scheme heterojunction photocatalyst not only reduces the rate of electron-hole pair compounding, but also maintains the redox properties of the photocatalyst and improves photocatalytic performance. In this paper, the mesoporous material TiO2/g-C3N4 S-Scheme heterojunction photocatalysts were prepared in one step by the sol-gel method using urea as a precursor. The particles of the prepared nanomaterials are between 20 and 50 nm in size and uniformly dispersed. The photodegradation efficiency of the photocatalyst for formaldehyde under visible light can reach over 85%. One-step preparation of TiO2/g-C3N4 photocatalysts by sol-gel method with simple preparation method and high yield, solving the difficulties of low yield and high requirements for temperature and environmental conditions in the preparation of g-C3N4 using urea thermal polymerisation.