Enhanced visible light photocatalytic water reduction from a g-C3N4/SrTa2O6 heterojunction
By Adhikari, Shiba P.; Hood, Zachary D.; Wang, Hui; Peng, Rui; Krall, Alex; Li, Hui; Chen, Vincent W.; More, Karren L.; Wu, Zili; Geyer, Scott; Lachgar, Abdou
Published in Applied Catalysis B: Environmental
2017
Abstract
Abstract A new g-C3N4/SrTa2O6 heterojunction photocatalyst was designed and prepared by chimie douce (soft chemistry) method where carbon nitride (g-C3N4) was deposited over the metastable perovskite phase of SrTa2O6. The morphological study of the heterojunction using {SEM} and {STEM} revealed that g-C3N4 nanofibers are dispersed uniformly on the surface of SrTa2O6 plates leading to the intimate contact between them. The heterojunction could achieve a high and stable visible light photocatalytic {H2} generation of 137 mmol/h/mole of g-C3N4, which is much larger than the amount of hydrogen generated by one mole of pristine g-C3N4. A plausible mechanism for the observed enhanced photocatalytic activity for the heterojunction is proposed on the basis of effective charge separation of photogenerated electron-hole pairs, supported by band position calculations and photo-physical properties of g-C3N4 and SrTa2O6.