In this study, a variety of heterostructured TiO 2 decorating graphitic carbon nitride (denoted as GCN/TiO 2 -x) photocatalysts is synthesized by using a simple calcination method. Among the prepared GCN/TiO 2 -x, GCN/TiO 2 -3.0 composites possess the remarkably lower recombination rates of electron-hole pairs (evidenced by photoluminescence) and more visible-light absorption (evidenced by ultraviolet/visible diffuse reflectance spectroscopy) as compared to pure GCN and TiO 2 , respectively. Accordingly, the GCN/TiO 2 -3.0 photocatalysts show the enhanced performance toward degradation of low-concentration formaldehyde (HCHO) (rate constant = 0.0043 min −1 ) that is much better than GCN (rate constant = 0.0012 min −1 ) and TiO 2 (rate constant = 0.0007 min −1 ) in the presence of visible light. This improvement observed for the photocatalytic degradation of gas phase HCHO can be probably caused by the heterojunction between GCN (the enhanced absorption of visible light) and TiO 2 (improved separation of photogenerated electron-hole pairs). The electron spin resonance (ESR) signals suggest the photogenerated superoxide radical anions (·O 2 -) and hole (h + ) may be responsible for the visible-light-driven photodecomposition of HCHO. This work provides a facile route to prepare efficient photocatalysts for indoor air purification by using interior lighting.
|Number of pages||8|
|Journal||Journal of Photochemistry and Photobiology A: Chemistry|
|Publication status||Published - 2019 Jun 1|
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Physics and Astronomy(all)