Synergetic improvement in charge carrier transport and light harvesting over ternary InVO4-g-C3N4/rGO hybrid nanocomposite for hydrogen evolution reaction

Abstract

A ternary reduced graphene oxide loaded InVO4-g-C3N4 nanocomposite was prepared by the wet impregnation method. The formation of InVO4-g-C3N4 heterojunction and loading of rGO was corroborated by XRD, FTIR, UV–vis, TEM and XPS studies. Incorporation of both InVO4 and rGO in g-C3N4 substantially increased the absorption edge of the photocatalyst from 451 nm (2.75eV) of g-C3N4 to 546 nm (2.27 eV) due to the formation of heterojunction. Interestingly, among the different weight % of both InVO4 and rGO loaded g-C3N4, 3.0 wt% of rGO and 30 wt% of InVO4 loaded g-C3N4 has shown a superior hydrogen production of 7449 μmol g−1h−1, a 45 times enhancement in comparison to g-C3N4. This can be related to the synergetic boosting of charge carrier separation at InVO4-g-C3N4 heterojunction and transportation through rGO support as revealed by photoluminescence and photocurrent studies. Moreover, the hydrogen production rate obtained in the present binary nanocomposite was almost 8 times higher than the previously reported hydrogen production rate using the same binary InVO4-g-C3N4 nanocomposites without rGO support.