Electrochemical energy storage application of CuO/CuO@Ni–CoMoO4·0.75H2O nanobelt arrays grown directly on Cu foam

Supercapacitors are attracting huge research interest because they are expected to achieve battery-level energy density, and they have a longer calendar life and shorter charging time. However, due to the out shell materials without contact extra freeway for charge transports, the out shell materials have still limited contribution to high capacitance for array structure at high rates. Here, CO/[email protected] NBs were designed and synthesized on Cu foam substrates with CuO NBs as cores or extra freeway and Ni–CoMoO4·0.75H2O nanobelt as shell by an easily synthetic method. CuO NBs will provide electron "superhighways" and extra outside freeway for charge storage and delivery. Besides, the Ni doped CoMoO4·0.75H2O NBs are conducive to the electrical conductivity, and open space among these nanosheets can act as an "ion reservoir", the increment of active sites and the contribution of capacitive effects. Finally, the [email protected] NBs directly grown on Cu foam could avoid the "dead" volume caused by the tedious process of mixing active materials with polymer binders/conductive additives. As expected, the CO/[email protected] NBs exhibited the high specific capacitance, the good rate performance and the excellent electrochemical stability.