Solar-reduced graphene oxide heterostructure: A sustainable Bi-functional photocatalyst producing clean hydrogen from water and enabling organic dye degradation

This study delves green synthesis of a solar-reduced graphene oxide (SrGO) and graphitic carbon nitride (g-C3N4) heterostructure by utilizing solar energy as a crucial component of the synthesis process. SrGO/g-C3N4 heterostructure demonstrated enhanced optical absorption and strong interfacial connection between SrGO and g-C3N4 interface. Comprehensive spectroscopic and microscopic analyses provided a detail understanding of heterostructural properties, confirming its suitability for solar-driven applications. Under solar irradiation, g-C3N4 nanosheet showed photocatalytic H2 evolution of 244.01μmolh−1g−1Cat. The coupling of SrGO with different wt% decreased the energy bandgap of g-C3N4 and increased the separation of photoelectrons and hole pairs. The 1 wt%SrGO/g-C3N4 heterostructure demonstrated excellent photocatalytic H2 evolution activity 2071.3μmolh−1g−1Cat, 8.4-fold greater than pure g-C3N4. The heterostructure exhibited exceptional stability and excellent Apparent Quantum Yields (7.31 %) at 460 nm. Further, 1 wt%SrGO/g-C3N4 indicated 97.16 % photocatalytic degradation of RhB dye within 75 min with increased reactivity of 0.0436 min−1 as compared to 0.00696 min−1 for 0.5 wt% SrGO/g-C3N4 and 0.01031 min−1 for 1.5 wt% SrGO/g-C3N4, respectively. Moreover, 1 wt% SrGO/g-C3N4 shows the highest Jph (370μA/cm2 at 1V versus RHE) and photogenerated charge carrier lifetime τ = 1.210×10−8. The mechanism of photocatalytic performance of SrGO/g-C3N4 heterostructure was examined in detail.