Layered Al‐substituted Cobalt Hydroxides/GO Composites for Electrode Materials of Supercapacitors

Abstract

In this work, Al-substituted α-Co(OH) 2 /GO composites with supercapacitive properties were prepared by chemical co-precipitated method in which cobalt nitrate and aluminum nitrate were used as the raw material, and graphite oxide was employed as carrier. The as-prepared materials were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and fourier transform infrared spectroscopy (FT-IR). Cyclic voltammetry (CV) and galvanostatic charge/discharge measurements showed that the Al-substituted α-Co(OH) 2 /GO electrode material had excellent electrochemical capacitance. The specific capacitance of 1137 F•g -1 was achieved in 6 mol/L KOH solution at a current density of 1 A•g -1 within a potential range of 0-0.5 V. Moreover, only 12% losses of the initial specific capacitance were found after 500 cycles at a current density of 1 A•g -1 .

A Review of Cobalt-Based Metal Hydroxide Electrode for Applications in Supercapacitors

“…Aluminum nitrate or Al(NO 3 ) is a second choice to increase capacitance because it is close to pure 99%. Graphite electrodes are looked at here as catalysts because they have a high discharge potential than other materials [12]. An EDX analysis of the Co(OH) 2 alpha nanosheets confrmed that the Co 3+ ions were in the tetrahedral coordination for pure Co(OH) 2 [13].…”