Gold nanoparticles supported on layered TiO2–RGO hybrid as an enhanced and recyclable catalyst for microwave-assisted hydration reaction

Abstract

In this study, we synthesized a novel composite material (Au–TiO₂–RGO) consisting of tiny gold nanoparticles (∼4.5 nm) grown on a layered titania (TiO₂) and reduced graphene oxide (RGO) hybrid. After treatment with microwave and sulfuric acid, solid acid (SO₄²⁻/TiO₂) was in situ formed on the surface of TiO₂, and the resulting Au–SO₄²⁻/TiO₂–RGO was determined as an enhanced catalyst for hydration reaction. The strong metal-support interaction (SMSI) between Au and TiO₂ and the cooperative effect between Au and SO₄²⁻/TiO₂ solid acid collectively account for the excellent performance. Moreover, due to the versatile RGO substrate, the catalyst could also be recycled and reused at least 5 times without obvious deactivation.