Synthesis and Characterization of Nickel�Magnesium Catalyst Supported on Reduced Graphene Oxide

In this study, nickel�magnesium catalyst supported on reduced graphene oxide nanosheets was synthesized. rGO support was characterized by X-ray diffraction (XRD), surface area and porosity, and thermogravimetric analysis, and fourier-transform infrared (FTIR) and Raman spectroscopy to understand its physicochemical properties. The results revealed that the edge-oxidized rGO has high surface area (258.11 m2g�1) with approximately 36 multi graphitic layers where interlayer spacing is 0.336 nm each. High thermal stability of rGO makes it an excellent support to be used for high-temperature catalytic activity. Subsequently, rGO supported catalysts were synthesized via incipient wetness impregnation method. The amount of Ni was fixed at 20 wt whilst Mg was varied at 0 wt and 5 wt relative to rGO content to assess its effect as second metal towards properties of the catalyst. X-ray diffractograms of Ni20/rGO and Ni20Mg5/rGO demonstrated formation of new peaks due to presence of NiO and NiO�MgO whereas (002) rGO peak at 26.5° does not show obvious changes, concluding the stability of rGO after the impregnation and calcination processes. Upon impregnation, the surface area and porosity of Ni20/rGO is lower than that of rGO due to dispersion of Ni metal on the rGO surface. BET surface area of Ni20Mg5/rGO catalyst further decreases to 103.95 m2g�1 due to the addition of metal content but its porosity is higher than Ni20/rGO. Hence, it is postulated that Ni and Mg metal form solid solution (NiO�MgO) on rGO nanosheets which has bigger particle size compared to NiO, lowering its penetration into rGO mesopores. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.