In the present work, the effect of graphene oxide (GO) architecture and synthesis of gold nanoparticles (AuNPs) on the surface of GO by using Euphorbia leaf extract was investigated. The as-synthesized catalyst was utilized for reduction of 4-nitrophenol (4- NP) and methylene-blue (MB). The ethanol/water extract of the leaves of Euphorbia was found as a non-toxic, suitable, ecofriendly natural reducing agent in one-step generation of Au nanoparticles onto the GO. The catalyst was characterized by different analysis such as atomic force microscopy, powder X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, SEM-mapping, transmission electron microscopy, and atomic absorption spectrometry. The high catalytic performance of the surfactant exfoliated gold-GO (SE-AuNPs/GO) towards the reduction of 4-NP to 4- aminophenol (4-AP) and reduction of MB to leucomethylene blue (LMB) under mild conditions, in water and at room temperature, was exhibited.
