Construction of ZnFe2O4/g-C3N4 nanocomposite catalyst for degradation of organic compound through photodegradation and heterogeneous Fenton oxidation

Abstract

ZnFe2O4/g-C3N4 heterojunction nanocomposite photocatalyst was prepared by one-step solvothermal method using graphite carbon nitride (g-C3N4) and zinc ferrate (ZnFe2O4), and characterized by SEM/EDX, XRD, FT-IR, Zeta potential, and VSM. The cationic-dye methylene blue (MB) was selected as the target pollutant for photocatalytic degradation and the degradation mechanism of the heterogeneous nanocomposite photocatalyst was analyzed. The photocatalyst can accelerate the separation of photogenerated electron-hole pairs, increase the number of photocatalytic reaction sites, and have strong REDOX ability and charge transport ability. The degradation efficiency of MB is 3 times and 2 times of that of pure g-C3N4 and ZnFe2O4, respectively. Visible light (Vis)/ZnFe2O4/g-C3N4/sodium percarbonate (SPC) photo-Fenton system established under the synergistic effect of ZnFe2O4/g-C3N4 and SPC can continuously produce ·OH, ·O2− and h+. In half an hour, 93% of MB was degraded by Vis/ZnFe2O4/g-C3N4/SPC, and the degradation rate of MB was above 90% for 5 consecutive cycles. Through characterization and water treatment experiments, ZnFe2O4/g-C3N4 heterostructure nanocomposite photocatalyst has the characteristics of high efficiency photocatalytic oxidation activity, stability, superparamagnetism, easy separability and reusability, and can be reused continuously. Therefore, it is a promising photocatalyst in the field of wastewater treatment and a potential candidate material for the treatment of refractory organic pollutants.