Synthesis of composite electrodes for supercapacitors based on carbon materials and the metal oxide/metal hydroxide system

Abstract

In this article, the properties of composites based on activated carbon-fiber material of UVIS-AK-V-240 brand and an oxygen-containing compound of transition metals (MnO2, Ni(OH)2, Co(OH)2) obtained by anaphoresis from colloidal solution containing the corresponding compounds were investigated. It was determined that composites together possessed a higher capacitance than did the initial components individually. The maximum specific capacitance was obtained on the UVIS-Ni(OН)2 composite (~370–380 F/g). For all the investigated materials, the specific capacitance increases with a decrease in the potential scan rate. It was determined that the materials obtained by the sol–gel method possess mixing and cataphoresis inferior to the value of the specific capacitance of the materials obtained by anaphoresis—by up to around four orders of magnitude, depending on the method of their obtaining. On the basis of micrographs of composite materials, it was shown that the shape, structure, and distribution of precipitate by the fiber and volume of material depend on the composition and solution concentration.