▎ 摘 要
AgxPt100-x (x=0, 25, 50, 75 and 100) nanoparticles were grown on the surface of magnetic graphene oxide nanosheets (Fe3O4@GO) for the first time. The as-prepared nanocomposites were characterized using various techniques such as Fourier transform infrared spectroscopy, powder X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, Brunauer-Emmett-Teller surface area analysis, vibrating sample magnetometry and thermogravimetric analysis. The Fe3O4@GO-AgxPt100-x catalysts were applied in the reduction of 4-nitrophenol (4-NP) to 4-aminophenol using sodium borohydride (NaBH4). The synthesized nanocomposites exhibited excellent catalytic performance in the reduction of 4-NP with high recyclability for five consecutive runs. The Fe3O4@GO-Ag75Pt25 nanocomposite exhibited the best catalytic activity with a rate constant as high as 140.6x10(-3)s(-1). The obtained kinetic data were modelled with the Langmuir-Hinshelwood equation. The energy of activation and thermodynamic parameters including enthalpy, entropy of activation and activation Gibbs free energy were calculated.