MnO2 nanosheets grown on the ZnO-nanorod-modified carbon fibers for supercapacitor electrode materials

A kind of new hierarchical ZnO@Au@MnO2 core-shell nanowire structure has been designed and constructed for supercapacitor electrode materials. The nanostructure is produced by forming ultrathin self-standing MnO2 nanosheets on Au-coated ZnO nanowires grown radically on carbon fiber paper. A specific capacitance of 654 F/g at a scan rate of 2 mV/s by cyclic voltammetry and 478 F/g at a current density of 2.6 A/g are achieved for the ZnO@Au@MnO2 nanostructure electrode in 1.0 M Na2SO4 aqueous solution. In addition, the hybrid nanostructure shows an excellent long-term cycling stability. 80% of its initial capacitance remained after 2500 cycles at a large scan rate of 50 mV/s. The improved electrochemical performance of the new ZnO@Au@MnO2 core-shell nanostructure endows it a potential value as electrode materials for next generation supercapacitors. (C) 2014 Elsevier B.V. All rights reserved.