Characteristics and electrochemical performances of lotus-like CuO/Cu(OH)2 hybrid material electrodes

The hierarchical structure of flower-like CuO standing on Cu(OH)2 nanowire arrays was directly fabricated on the surface of copper foil via a simple and cost-effective liquid–solid reaction. The morphology and structure of lotus-like CuO/Cu(OH)2 hierarchical arrays were examined by scanning electron microscopy and X-ray diffraction spectroscopy. Under varying polarization cut-offs and scan rates, cyclic voltammetry curves display the lotus-like CuO/Cu(OH)2 array electrode with highly reversible features and good rate abilities, respectively. Significantly, this lotus-like CuO/Cu(OH)2 array electrode exhibited the excellent specific capacitance of 278 Fg−1, which corresponds to the energy density of 23.3 Wh kg−1 by use of galvanostatic charge/discharge test at a current density of 2 mA cm−2. Capacitance loss of 15% over 5000 cycles further indicates suitability of the cupric complex oxide as a potential electrode material for supercapacitors.

► Flower-like CuO standing on Cu(OH)2 nanowire arrays was fabricated on copper foil.
► Electrode exhibited the capacitance of 278 Fg−1 with energy density of 23.3 Wh kg−1.
► Capacitance loss of 15% over 5000 cycles indicates suitability of copper oxide.