Hierarchical architectures of Co3O4 ultrafine nanowires grown on Co3O4 nanowires with fascinating electrochemical performance†
Abstract
A facile method to synthesize hierarchical architectures of Co3O4 nanowires@Co3O4 ultrafine nanowires grown on Ni foam was developed here. The unique architectures consisting of numerous ultrafine Co3O4 nanowires (shell) well grown on the surface of a Co3O4 nanowire (core) delivered remarkable electrochemical performance with ultrahigh specific capacitance (1640 F g−1 at a current density of 2 mA cm−2), superior rate capability (66% retention of the initial capacitance from 2 mA cm−2 to 50 mA cm−2) and outstanding cycling stability (∼99.03% retention of the initial capacitance after 10 000 cycles). Such fascinating capacitive behaviors can make these hierarchical architectures of Co3O4 nanowires@Co3O4 ultrafine nanowires promising electrode materials in electrochemical applications.