Determining the optimal hydrothermal synthesis temperature and manganese percentage in the NiCoMn ternary-metal oxide deposited on nickel foam for pseudocapacitor applications

Abstract

Supplying energy from alternative sources than fossil fuels has become one of the essential needs of human society. To do this, it is necessary to store energy from these alternative sources. The use of pesudocapacitors as an energy storage system is a valuable route for this. In this study, the trimetallic structure of NiCoMn was synthesized on a nickel foam bed with different molar ratios, time, and temperature with the hydrothermal method. Then by optimizing the molar ratios of metals, synthesis temperature, and time using electrochemical tests, the structural characteristics and electrochemical performance of the samples were investigated. The nanostructure of the synthesized samples at various times was in the form of sheets that were placed together creating a network of nanosheets. The electrochemical galvanostatic charge-discharge performance of the Ni₈Co₂Mn0.5 % (190 ℃-15h) sample was better than for the other samples. This sample had the longest discharge time and as a result, the highest capacity (439.12 F.g⁻¹). The electrochemical impedance spectroscopy test, in agreement with other tests, showed a low resistance of 65.24 Ω; for this sample.