▎ 摘　　要

In this work, graphene supported graphitic carbon nitride (g-C3N4, GCN) photocatalyst was used for photo activation of peroxymonosulfate (PMS) oxidant. Coupling with graphene (Gr) upgraded photocatalytic performance of g-C3N4 (GCN), as graphene increased surface area, acted as a sink/support material and reduced charge carriers recombination. PMS assisted photodegradation processes had superior malathion pesticide degradation efficiency in 5 h. Peroxymonosulfate activation by graphene supported graphitic carbon nitride (Gr/GCN/PMS) exhibited higher malathion degradation than other photocatalysts and followed the removal order: 94% (Gr/GCN/PMS) > 72% (Gr/GCN) > 65% (GCN/PMS) > 45% (GCN) > 30% (Gr). Likewise, 94% removal of Escherichia coli (E. coli) was observed by Gr/GCN nanocomposite in 6 h under visible light. Scavenging studies confirmed the important role of holes (h(+)), hydroxyl ((OH)-O-center dot) and superoxide (SO4 center dot) radicals in photodegradation processes which was further validated by possible mechanism. (C) 2020 Elsevier B.V. All rights reserved.