Construction of mesoporous CuMn2O4/g-C3N4 heterojunctions as effective photocatalysts for reduction and removal of mercury ions

In this work, CuMn2O4/g-C3N4 photocatalysts with variations of CuMn2O4 NPs percentages (0.5-2%) have been performed as effective photocatalyst for reduction of Hg(II) ions during illumination by visible light. Well-crystalline spinel CuMn2O4 NPs were fabricated, and they were distributed onto g-C3N4 nanosheets with a uniform size of similar to 10 nm. The coupling CuMn2O4/g-C3N4 photocatalyst is much better than that of bare g-C3N4 and CuMn2O4. Notably, the reduction efficiency of 1.5% CuMn2O4/g-C3N4 photocatalyst was enhanced 3 and 9 times contrasted with bare CuMn2O4 and g-C3N4. The rate constant of 1.5% CuMn2O4/g-C3N4 photocatalyst was promoted by 9.6- and 6.2-folds larger than bare g-C3N4 and CuMn2O4. Significantly, the construction of heterojunction CuMn2O4/C3N4 photocatalyst enhanced the absorption in visible light and improved the carrier separation and generation. There was no significant loss in Hg(II) reduction after five successive cycles of experiments, indicating that CuMn2O4/g-C3N4 exhibited outstanding photocatalytic stability. The procedure approach in the present work is anticipated for constructing nanocomposites with advanced properties and novel morphologies in photocatalysis, electrochemical, and gas sensing applications.