Design and synthesis of CoMoO4–NiMoO4·xH2O bundles with improved electrochemical properties for supercapacitors

Abstract

CoMoO₄–NiMoO₄·xH₂O bundles with excellent electrochemical behavior were designed and synthesized by a facile strategy. CoMoO₄ nanorods were fabricated by a chemical co-precipitation method, and then CoMoO₄–NiMoO₄·xH₂O bundles were prepared by the same method using the CoMoO₄ nanorods as the backbone material. A growth mechanism was proposed to explain the formation of the bundles. The composites combine the advantages of the good rate capability of CoMoO₄ and the high specific capacitances of NiMoO₄·xH₂O, showing higher specific capacitances than CoMoO₄ and a better rate capability than NiMoO₄·xH₂O. A maximum specific capacitance of 1039 F g⁻¹ was achieved at a current density of 2.5 mA cm⁻², and 72.3% of this value remained at a high current density of 100 mA cm⁻². The excellent electrochemical performance makes the composite a promising electrode material for electrochemical capacitors.