Hetero-nuclear coordinated compounds for use in high-performance supercapacitor electrode material design

Abstract

Single crystals of cobalt coordination compounds were obtained by one-pot hydrothermal reaction. Nickel ion exchange was used to produce the Ni–Co hetero-metal compound with tunable chemical composition. Using a nickel-exchanged compound as the precursor, we developed a simple chemical reaction to synthesize large-scale 3D hierarchical Ni_xCo_3−xS₄ (x = 0.15–0.42) microflowers under ambient conditions. As an electrode material for supercapacitors, the discharge capacitance of Ni_0.42Co_2.58S₄ microflowers is approximately one and a half times higher than the discharge capacitance value of Ni_0.15Co_2.75S₄ at a current density of 0.5 A g⁻¹.