In-situ synthesis of Fe and O co-doped g-C3N4 to enhance peroxymonosulfate activation with favorable charge transfer for efficient contaminant decomposition

Iron and oxygen co-doped graphite phase carbon nitride ([email protected]CN) is synthesized via a simple one-pot in-situ pyrolysis method. It is used in a favorable peroxymonosulfate (PMS) activation oxidation system to enhance Orange I (OI) degradation. The effects of dopant contents, different water conditions and the reusability are conducted to evaluate the removal efficacy of PMS catalytic over [email protected]CN in water. Moreover, OI degradation is almost stable under several typical anions (H2PO4−, Cl− and HCO3−) and humic acid existence. Theoretical calculation results reveal that effective-directional transfer of electrons is obtained by [email protected]CN, building the formation of high electron density areas around Fe and O. The quenching tests display that O2•− and 1O2 are responsible for OI removal, and SO4•− and •OH only donate a very small contribution. The electron transfer between electron-rich Fe, O element and HSO5− cycles facilitate HSO5− activation to generate reactive oxygen species. After co-doping, DFT calculations confirm the stronger binding energy, greater charge transferability and longer OO bond length for PMS activation in [email protected]CN/PMS system. Our findings provide a valuable insight for the development of efficient catalysts for PMS activation via metal and nonmetal co-doping, which display a promising application for polluted aquatic environment.