▎ 摘　　要

We report a simple two-step method for the synthesis of reduced graphene oxide supported NiCo2O4 nanoparticles (RGNCO) as a potential active catalyst for the reduction of p-nitrophenol with NaBH4. Various characterization techniques were employed to investigate the morphology, structure and surface composition of the catalyst. The results confirm successful anchoring of NiCo2O4 on the graphene sheets and suggests the presence of oxygen vacancies. The as prepared RGNCO catalyst exhibited good stability and excellent catalytic property with an activity factor of 356.5 min-1 g-1, which is greater than the highest value reported in literature for NiCo2O4 based catalysts. The improved catalytic performance is due to the synergistic effect of reduced graphene oxide and oxygen vacancy rich NiCo2O4 nanoparticles. The effect of different reaction parameters like temperature, quantity of catalyst, concentration of reactants, and presence of different anions on the catalytic property were investigated in detail. The surface catalysed p-nitrophenol reduction using RGNCO catalyst was successfully modelled using the Langmuir-Hinshelwood mechanism. The ability of the RGNCO catalyst to reduce a relatively large volume of PNP solution (20 ml) with an activity factor comparable to that of noble metal-based catalysts signifies the novelty of the material and makes it a potential candidate for practical environmental catalytic applications.