Hierarchical shell/core electrodes with CuO nanowires based on carbon cloths for high performance asymmetric supercapacitors

Abstract Transition metal oxides/hydroxides are important pseudocapacitive materials for supercapacitors, however, low electron transfer capability and poor long-term cycle stability limit their applications. Constructing transition metal oxide/hydroxide nanoarrays on conducting collectors is an effective way to solve the above problems. In this thesis, CuO nanowires based on carbon cloths (CuO–CCs) were firstly grown by chemical copper plating and thermal oxidation, and then Ni(OH)2@CuO–CCs and Fe2O3@CuO–CCs were constructed by chemical bath deposition and hydrothermal methods, respectively. The ASC device using Ni(OH)2@CuO–CCs as positive electrodes and Fe2O3@CuO–CCs as negative electrodes were assembled. The results demonstrate that the optimal specific capacities of Ni(OH)2@CuO–CCs and Fe2O3@CuO–CCs are 2.282 F cm−2 (at 1 mA cm−2) and 0.772 F cm−2 (at 2.5 mA cm−2), respectively. The ASC device reaches the energy density of 81.12 Wh kg−1 at a power density of 2.88 kW kg−1, and exhibit the capacitance maintenance of 97.9% after 10,000 cycles.