Three-dimensional network space Ag3PO4/NP-CQDs/rGH for enhanced organic pollutant photodegradation: Synergetic photocatalysis activity/stability and effect of real water quality parameters

In this report, a N, P co-doped carbon quantum dots (N, P-CQDs) modified silver phosphate united graphene hydrogel (Ag3PO4/NP-CQDs/rGH) photocatalyst with three-dimensional network space structure was designed to build a synergetic photocatalytic activity/stability effect for organic pollutants degradation, which could be confirmed by characterization and photodegradation performance experiments. Convert-light via N, P-CQDs exactly matched for Ag3PO4 could induce more photocarrier generation, meanwhile the N, P-CQDs as an electron acceptor could accelerate the charge separation for anti-photocorrosion. This special network space structure in Ag3PO4/NP-CQDs/rGH photocatalyst provided more reaction active sites to accelerate mineralized reaction process. The photodegradation efficiency of TC in composed wastewater and real wastewater were tested with fresh and used Ag3PO4/NP-CQDs/rGH as photocatalyst. Specifically, the tetracycline hydrochloride (TC) removal rate with Ag3PO4/NP-CQDs/rGH (6%) was found to increase by 20% that of Ag3PO4 and 14% that of N, P-CQDs/Ag3PO4, and the organic pollutants removal efficiency with Ag3PO4/NP-CQDs/rGH photocatalyst maintained at 91.5% at 6th cyclic experiment. Meanwhile, the fresh and after photodegradation efficiency of Ag3PO4/NP-CQDs/rGH (6%) was maintained over 75% in real water matrix. The possible degradation pathway of TC was explored and the photodegradation mechanism was verified by the predominant induce active species (O-center dot(2)- and h(+)) in the photocatalytic system. As the consequence, the 3D network space structure Ag3PO4/NP-CQDs/rGH could be applied for sustaining organic pollutants photodegradation in the natural environment production.