Electrochemical hydrogen storage properties of NiAl2O4/NiO nanostructures using TiO2, SiO2 and graphene by auto-combustion method using green tea extract

Abstract

NiAl2O4/NiO nanostructures were synthesized via an auto-combustion method using green tea extract. TiO 2 , 12 SiO 2 , and graphene were used in order to enhance the electrochemical hydrogen storage performance of 13 NiAl2O4 . The structural analysis of host texture confirmed the formation of NiO alongside with NiAl 2O4 . 14 Furthermore, the formation of nanocomposites and distribution of the additives on the surface of 15 NiAl2O4/NiO nanostructures were affirmed by XRD and EDS spectra. The morphological analyses were 16 displayed the nanoscale formation of the particles. Interestingly, the electrochemical hydrogen storage of the 17 nanocomposites indicated that upon addition of TiO 2, SiO 2 and graphene, the discharge capacity enhanced as 18 compare to the host material. The maximum discharge capacities of NiAl 2O4 /NiO and its respective 19 nanocomposites containing SiO 2, graphene, and TiO 2 were observed at 850, 2000, 2750 and 3000 mAh/g, 20 respectively.