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.