Facile construction of novel ZnO and TiO2 combined g-C3N4 nanocomposite for superior visible-light photocatalytic organic pollutant degradation

A novel g-C3N4/ZnO-TiO2 nanocomposite was prepared by facile calcination and hydrothermal assisted route to boost the photocatalytic efficiency of g-C3N4. The structural, morphology and optical properties of as-obtained nanocomposites (NCs) were examined by various physicochemical methods such as XRD, FT-IR, FESEM-EDX, HR-TEM, UV-DRS and PL spectra relatively. The as-obtained g-C3N4/ZnO-TiO2 heterojunction NCs displays an optimum efficiency (93.6%) and high photo-degradation rate constant towards the photo-degradation of RhB dye in 75 min under visible-light exposure. Likewise, the synergistic effects on heterostructure strong-coupling interfaces assembly of g-C3N4 and TiO2/ZnO NPs, which facilitates the excellent photo-excited charge separation efficiency, suppressing the recombination rate and also widening the visible-light fascination ability. Hence, the resulting in a prolonged lifetime leading to continuous generation of h(+) and (OH-)-O-center dot species which were eventually improved the photo-degradation process. Also, the as-obtained hybrid g-C3N4/ZnO-TiO2 photocatalysts (PCs) revealed superior recycling stability. Moreover, a probable photocatalytic reaction mechanism of the novel PCs was also suggested.