POM-derived MoO3/CoMoO4 mixed oxides directed by glucose for high-performance supercapacitors

Abstract

In this work, polyoxometalate (POM) derived MoO₃/CoMoO₄ composites were prepared by a facile hydrothermal method and subsequent calcination process utilizing carbonized glucose as the template. Detailed characterization showed that Co and Mo species coated carbon spheres could be synthesized via the hydrothermal treatment of Co₂Mo₁₀ POM and glucose, which transformed into polyhedron MoO₃/CoMoO₄ particles after calcination. The electrochemical results indicated that the optimized MoO₃/CoMoO₄-40 could display the best electrochemical performances, including remarkable specific capacity (951.5 C g⁻¹ at 1 A g⁻¹) and outstanding cycle life (92.7% capacity retention after 5000 cycles). Furthermore, the MoO₃/CoMoO₄-40//AC asymmetric supercapacitor (ASC) fabricated by MoO₃/CoMoO₄-40 and activated carbon (AC) exhibited a high energy density of 54.7 W h kg⁻¹ at a power density of 812.1 W kg⁻¹, and capacitance retention of 93.5% at 8 A g⁻¹ after 5000 charge/discharge cycles. These results demonstrated that the present method is a simple and efficient strategy for the construction of high performance supercapacitor materials.