凯发

We study the in-situ synthesis of Au nanoparticles (Au NPs) on NaBH4-reduced RGO film. And this as-prepared Au NPs /RGO hybrid material was used to catalyze the reduction of 4-nitrophenol(4-NP). Without adding additional reductant or surfactant during the in-situ synthesis process, Au NPs were prepared by the reduction of RGO to Au3+ and have an uniform and a controllable coverage on RGO film, which greatly weaken the hydrophobic of RGO and turn the hybrid into a hydrophilic material, thus can disperse in the reaction system stably. In addition，there are no surfactants capped on the surface of Au NPs, which ensures the fully-contact between the surface active sites of Au NPs and reactants，which can improve the catalytic rate considerably. The results show that the Au NPs/RGO hybrid can end the reduction reaction of 4-NP in 150s with a kinetic constant as high as 1.21min-1, which is much higher than adding the same molar weight of single Au NPs. This hybrid can still end the reaction in 240s after holding at ~4 ºC for 40 days, which exhibits an excellent and stable catalytic activity.