Chief Investigator:

Dr. HO Wing Kei

Project Year:

2019-2020

Description:

In this project, we suggest a new strategy to change the photocatalytic selectivity of different visible-light-driven photocatalysts by controlling their surface defects in NOx removal. Our preliminary results show that introducing abundant surface defect sites such as carbon vacancy (Cv) on the surface of graphitic carbon nitride (g-C3N4) photocatalysts can promote visible light absorption, enhance the separation and transfer of photogenerated charge carriers and favour strong chemisorption of NO, leading to high photo reactivity. Meanwhile, the surface defects of g-C3N4 acted as electronic traps to localize the photogenerated electrons shift the adsorption structure of NO from C-N-O for the bulk counterpart to Cv-O-N. The localization of both the photogenerated electron and NO molecule to the same site leads to the direct electron transfer from vacancy defect to NO, eventually resulting in its high selectivity of converting NO to N2.