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

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.