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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.

Au–Pd bimetallic nanoparticles (NPs) with core–shell structures have been successfully anchored on chemical exfoliated MoS2 (Au–Pd/MoS2) through a facile co-reduction method at room temperature. The Au–Pd/MoS2 hybrids were characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The pristine MoS2 nanosheets exhibit some peroxidase-like activity for the oxidation of 3,3,5,5-tetramethylbenzidine (TMB), and their catalytic activity is significantly enhanced by the deposition of Au–Pd NPs. A systematic study revealed that Au–Pd NPs with a mass ratio of 1 : 2 on MoS2 (Au1.0Pd2.0/MoS2) showed the highest catalytic activity compared with other counterparts. This excellent performance of the Au1.0Pd2.0/MoS2 hybrids should be ascribed to not only the intrinsic catalytic activity of MoS2, but also the complicated metal–metal and metal–support interactions.

Acid–base bifunctional catalysts are of particularly interest, but also present great challenges in synthesis and applications. In this study, acid–base bifunctional graphene oxide hybrids were obtained by the modification of graphene oxide (GO) through a silylation reaction and radical addition. The obtained bifunctional hybrids displayed high acid and base catalytic activities towards a typical one-pot acid–base reaction sequence called deacetalization–nitroaldol reaction.

Graphene has attracted increasing attention as a support for heterogeneous catalysis. Although successful preparation and excellent catalytic performance of many graphene based nanocatalysts have been demonstrated, graphene supported nanocatalysts with turnable catalytic behaviors remain unexplored. In this study, we report a strategy to prepare a graphene supported Au nanocatalyst with thermo-sensitive catalytic behaviors. This smart catalytic system was prepared by introducing the temperature-responsive poly(N-isopropylacrylamide) (NIPAAm) and Au nanoparticles to graphene oxide (GO) through reversible addition–fragmentation chain transfer polymerization and direct co-reduction of HAuCl4. The obtained GO–NIPAAm–Au hybrid was systematically characterized and showed interesting thermo-sensitive catalytic activity in the catalytic reduction of 4-nitrophenol.