Preparation of Janus nanosheets composed of gold/palladium nanoparticles and reduced graphene oxide for highly efficient emulsion catalysis.

Interface/emulsion catalysis is an effective approach for many organic and inorganic chemical reactions. Positioning catalysts at the interface is essential for highly efficient interface/emulsion catalysis. The sheet-like Janus nanostructures may have great advantages in stabilizing emulsions and improving reaction efficiency. In this work, by using a simple emulsion reaction and photodeposition, we successfully prepare the Janus nanosheets with opposite sides composed of AuNPs/PdNPs and reduced graphene oxide (rGO) respectively, referred to as AuNP-rGO/PdNP-rGO Janus nanosheets. Due to the distinct hydrophilicities on opposite sides, the prepared Janus nanosheets demonstrate high efficiency in emulsion stabilization and emulsion catalysis. By introducing the prepared PdNP-rGO and AuNP-rGO Janus nanosheets in emulsion reactions, highly efficient hydrogenation of p-nitroanisole and photocatalytic degradation of Nile red are demonstrated. This work provides a simple and cost-effective method to prepare Janus nanosheets and realize highly efficient emulsion reactions, and this strategy can be extended to promote many other interface/emulsion reactions.