Fabrication of 3D Co3O4–Ni3(VO4)2 heterostructured nanorods on nickel foam possessing improved electrochemical properties for supercapacitor electrodes

Abstract

Three-dimensional (3D) Co₃O₄–Ni₃(VO₄)₂ heterostructured nanorods on nickel foam with excellent electrochemical behavior were synthesized by a facile strategy. A growth mechanism was proposed to explain the formation of the composite. The composite combined separately the advantages of the good rate capability of Co₃O₄ and the high specific capacitances of Ni₃(VO₄)₂, and showed higher specific capacitances than Co₃O₄ and better rate capability than Ni₃(VO₄)₂. A maximum specific capacitance of 1401 F g⁻¹ and energy density of 31.2 Wh kg⁻¹ were achieved at a current density of 0.5 A g⁻¹, and 70.3% of this value was retained at a high current density of 8 A g⁻¹. After 1000 cycles, 98.3% and 90.9% was retained at 0.5 A g⁻¹ and 8 A g⁻¹, respectively. The excellent electrochemical performance renders the composite a promising electrode for supercapacitors.