The photocatalytic performance and active sites of g-C3N4 effected by the coordination doping of Fe(III)

Element doping is a simple and effective method to improve photocatalytic activity of g-C3N4. However, the doping model and mechanism of metal elements are still uncharacterized. In this study, we found that Fe(III) can be doped into g-C3N4 through the coordination between amidogen and Fe(III). After activity tests, it was found that this coordination doping of Fe(III) could enhance the RhB oxidation and Cr(VI) reduction activities of g-C3N4 in interesting ways, but it is not helpful for the NO-removal performance of g-C3N4. Characterization and calculation results show that the coordination of Fe(III) can not only improve the transfer of photogenerated electrons, but it also can passivate the carbon site of triazine rings, which is the active site of NO-removal. This study revealed some doping mechanisms and effect mechanisms of elemental metal in photocatalysis. (c) 2020, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.