Novel Ag3PO4 modified tubular carbon nitride with visible-light-driven peroxymonosulfate activation: A wide pH tolerance and reaction mechanism

In this study, we fabricated the novel Ag3PO4 modified tubular porous carbon nitride (Ag3PO4@TPCN12) photocatalyst and evaluated its photocatalytic activity under the visible light irradiation in the presence of peroxymonosulfate (PMS) through carbamazepine (CBZ) degradation in water. The apparent rate constant in Vis/10%Ag3PO4@TPCN12/PMS system (0.0927 min−1) exhibited great superiority over that in Vis/TPCN12/PMS (0.0227 min−1), Vis/Ag3PO4/PMS (0.0019 min−1), and even Vis/(Ag3PO4 + TPCN12)/PMS (0.0646 min−1) systems. Importantly, a wide pH tolerance (3.0–9.0) was shown in Vis/10%Ag3PO4@TPCN12/PMS system. Multifarious reactive species involving SO4•−, HO•, 1O2, and photo-generated holes primarily responsible for the CBZ degradation were verified. The degradation pathways of CBZ were proposed, and the ecotoxicity of CBZ degradation products was assessed. In general, the Vis/10%Ag3PO4@TPCN12/PMS system was capable of high stability and benign resistance of water matrix, showing a hopeful practical application potential for organic compounds degradation in water.