Visible-Light Driven Enhanced Photocatalytic Properties of rGO/Mn3O4/MoO3 Ternary Hybrid Nanocomposite

Abstract

In the present study, the nanostructured ternary hybrid composite of rGO/Mn3O4/MoO3 has been synthesized for photocatalytic studies investigated in visible light. The graphene oxide, rGO/Mn3O4, and rGO/Mn3O4/MoO3 nanocomposites were prepared by using the modified Hummers’ method, co-precipitation method, and hydrothermal method respectively. Organic dyes such as methylene blue and methylene violet were used for the degradation process. In rGO/Mn3O4/MoO3 hybrid, graphene oxide (GO) acts as an excellent electron conductor and manganese oxide (Mn3O4) decomposes the dye molecules within a short time. Molybdenum trioxide (MoO3) shows good photocatalytic activity towards organic pollutants as well as promotes oxygen evolution reaction. The physiochemical characterizations such as X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDX), FT-IR, and UV–vis spectroscopy analysis were carried out. Furthermore, the photocatalytic efficiency of the as-synthesized ternary composite was recorded as 95% which is much higher than the efficiency of individual components due to the synergetic effect of rGO. Two-dimensional structured GO increases the absorption sites which act as charge trapping centers which help to reduce electron-hole recombination effect. Photodegradation mechanism of methylene blue and methylene violet dyes for wastewater treatment application under ambient conditions has been discussed.