A novel Fenton-like catalyst of Ag3PO4/g-C3N4: Its performance and mechanism for tetracycline hydrochloride degradation in dark

Heterogeneous Fenton-like reaction has been extensively investigated for degradation of organic pollutants for waste treatment due to the formation of highly aggressive hydroxyl radicals from hydrogen peroxide. However, most heterogeneous Fenton-like catalysts still worked well under acid conditions/or with the help of light irradiation/ electrical field, which limits their applications. Here, a novel Fenton-like catalyst of Ag3PO4/gC3N4 was used for degradation of tetracycline hydrochloride (TCH, a typical emerging aqueous pollutant) for the first time in a wide pH value range (4.04-9.08) in dark. The results showed that it could effectively activate H2O2 to generate .OH and .O2- radicals in dark, which could oxidize the target pollutant in the all testing pH value range. It also showed a good stability in repeating test. The results of characterizations and theory calculation revealed a strong electronic interaction between Ag3PO4 and g-C3N4 improving the electron densities around Ag and O atoms in Ag3PO4 on the interface, which benefited the formation of active species. This work is expected to provide an insight for the design and fabrication of the novel highly-efficient Fenton-like catalysts for purification of waste water in a wide pH range.

Automated summary

A novel Fenton-like catalyst of Ag3PO4/gC3N4 was used for the first time in a wide pH range for degradation of tetracycline hydrochloride (TCH) in dark, showing effective generation of .OH and .O2- radicals from H2O2 to oxidize the target pollutant in all tested pH values and exhibiting good stability in repeated tests. The strong electronic interaction between Ag3PO4 and g-C3N4 on the interface is beneficial for the formation of active species. This work provides insights for the design and fabrication of highly-efficient Fenton-like catalysts for waste water purification across a wide pH range.