Enhanced electrochemical performance of MnNi <sub>2</sub> O <sub>4</sub> /rGO nanocomposite as pseudocapacitor electrode material and methanol electro-oxidation catalyst
Mohammad Bagher Askari, Parisa Salarizadeh, Antonio Di Bartolomeo, Fatih Şen
Abstract
Abstract Binary transition metal oxides with encouraging electrocatalyst properties have been suggested as electrode materials for supercapacitors and methanol oxidation. Hence, in this work, a binary mixed metal oxide based on nickel and manganese (MnNi 2 O 4 ) and its hybrid with reduced graphene oxide were synthesized by a one-step hydrothermal method. After physical and morphological characterization, the potential of these nanostructures was investigated for use as supercapacitor electrodes and methanol electro-oxidation. The results of the electrochemical analysis showed a substantial effect of adding rGO to the MnNi 2 O 4 . The MnNi 2 O 4 /rGO hybrid electrode supercapacitor exhibited good stability of 93% after 2000 consecutive CV cycles and a specific capacitance of 575 F g −1 at the current density of 0.5 A g −1 . Furthermore, the application of this hybrid nanomaterial in the methanol electro-oxidation reaction (MOR) indicated its appropriate electrochemical efficiency and stability in methanol oxidation. Our results show that MnNi 2 O 4 /rGO can be considered as a promising electrode material for energy applications.