Insights into peroxymonosulfate activation under visible Light: Sc2O3@C3N4 mediated photoexcited electron transfer

Generation of reactive radicals via photocatalytic peroxymonosulfate (PMS) is restricted by the sluggish kinetics of PMS decomposition and lack of electron transfer channel. Herein, we firstly prepared rare earth oxide functionalized carbon nitride (5-ScO-CN) by simple in-situ one-step calcination method, and surprisingly found it mediated photoexcited electron transfer between PMS and organic contaminants to boost PMS based oxidation decontamination. Rare earth oxide proceeds as active sites to mediate electron transfer from organic contaminants and PMS under visible light irradiation, it concurrently elevates fast oxidation of organic contaminant and activation of PMS to produce reactive radicals to further oxidize organic contaminants. We conducted density functional theory (DFT) calculation and galvanic oxidation process (GOP) to further unveil the role of 5-ScO-CN for mediating photoexcited electron transfer and generation of reactive radicals. This work proposes a novel mechanism for visible light boosted PMS based oxidation and provides a novel strategy for application of photocatalytic oxidation in environmental remediation field.