Abstract: A chemical precipitation-thermal decomposition method was developed to synthesize Co₃O₄ nanoparticles using cobalt liquor obtained from the atmospheric pressure acid leaching process of nickel laterite ores. The effects of the precursor reaction temperature, the concentration of Co²⁺, and the calcination temperature on the specific surface area, morphology, and the electrochemical behavior of the obtained Co₃O₄ particles were investigated. The precursor basic cobaltous carbonate and cobaltosic oxide products were characterized and analyzed by Fourier transform infrared spectroscopy, thermogravimetric differential thermal analysis, X-ray diffraction, field-emission scanning electron microscopy, specific surface area analysis, and electrochemical analysis. The results indicate that the specific surface area of the Co₃O₄ particles with a diameter of 30 nm, which were obtained under the optimum conditions of a precursor reaction temperature of 30℃, 0.25 mol/L Co²⁺, and a calcination temperature of 350℃, was 48.89 m²/g. Electrodes fabricated using Co₃O₄ nanoparticles exhibited good electrochemical properties, with a specific capacitance of 216.3 F/g at a scan rate of 100 mV/s.