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

• Ag 3 PO 4 /g-C 3 N 4 was used for degradation of TCH for the first time in dark. • It can effectively oxidize and degrade TCH in a wide pH value range. • The ⋅OH and ⋅O 2 – radicals are the main active species. • A strong interface interaction improves the electron densities around Ag and O atoms. • The possible catalytic mechanism was proposed. 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 Ag 3 PO 4 /g-C 3 N 4 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 H 2 O 2 to generate ⋅OH and ⋅O 2 – 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 Ag 3 PO 4 and g-C 3 N 4 improving the electron densities around Ag and O atoms in Ag 3 PO 4 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.