▎ 摘　　要

In this research, a novel approach has been investigated for the fabrication of functionalized two-dimensional graphene oxide and promoted with phosphotungstic acid. First, PVP units with medium molecular weight were placed between graphene sheets for preparation of two-dimensional graphene oxide and then the surface of 2D-graphene oxide modified with (3-chloropropyl)triethoxysilane and metformin respectively. Finally, prepared support prompted with phosphotungstic acid which has the role of the active sites. This catalyst was characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FT-IR). 2D-GO-CPTES-Met/H3PW12O40 have been used for the catalytic reduction of methyl orange (MO) and methylene blue (MB) in the presence of NaBH4 as a reducing reagent. The progress of the reaction was monitor by UV-Vis spectrophotometry at different times. The obtained kinetic data for the reduction of MO and MB were fitted to first-order rate equations and the calculated rate constants for the reduction of MO and MB were as follows 0.020 and 0.102 s(-1), respectively. The catalytic activity over 2D-GO-CPTES-Met/H3PW12O40 recycled catalyst remained at a satisfactory state after at least 10 runs.