To push the energy density limit of supercapacitors, proper pseudocapacitive materials with favorable nanostructures are urgently pursued. Ternary transition metal sulfides are promising electrode materials due to the better conductivity and higher electrochemical activity in comparison to the single element sulfides and transition metal oxides. In this work, we have successfully synthesized porous CuCo2S4 nanorod array (NRAs) on carbon textile through a stepwise hydrothermal method, including the growth of the Cu-Co precursor nanowire arrays and subsequent conversion into CuCo2S4 NRAs via anion exchange reaction. The CuCo2S4 NRAs electrode exhibits a greatly enhanced specific capacitance and an outstanding cycling stability. Moreover, an asymmetric supercapacitor using the CuCo2S4 NRAs as positive electrode and activated carbon as negative electrode delivers a high energy density of 56.96 W h kg−1. Such superior performance demonstrate that the CuCo2S4 NRAs are promising materials for future energy storage applications.

As a new class of pseudocapacitive material, metal sulfides possess high electrochemical performance. However, their cycling performance as conventional electrodes is rather poor for practical applications. In this article, we report an original composite electrode based on NiCo2S4@NiO core-shell nanowire arrays (NWAs) with enhanced cycling stability. This three-dimensional electrode also has a high specific capacitance of 12.2 F cm−2 at the current density of 1 mA cm−2 and excellent cycling stability (about 89% retention after 10,000 cycles). Moreover, an all-solid-state asymmetric supercapacitor (ASC) device has been assembled with NiCo2S4@NiO NWAs as the positive electrode and active carbon (AC) as the negative electrode, delivering a high energy density of 30.38 W h kg−1 at 0.288 KW kg−1 and good cycling stability (about 109% retention after 5000 cycles). The results show that NiCo2S4@NiO NWAs are promising for high-performance supercapacitors with stable cycling based on the unique core-shell structure and well-designed combinations.

Different nanostructures of copper oxide (CuO) by in-situ growth on carbon clothes (CC) are prepared to develop ultrasensitive non-enzymatic glucose sensors. The electrochemical performance of the CuO-based electrodes for detecting glucose has been investigated by cyclic voltammetry (CV) and chronoamperometry. The CuO nanosheets (CuO NSs)/CC electrode demonstrates a high sensitivity of 4902 μA mM -1 cm -2 at an applied potential of 0.55 V (vs. Ag/AgCl/ 3M KCl) in alkaline solution, and it shows 2973 μA mM -1 cm -2 and 1246 μA mM -1 cm -2 for the CuO nanowires (CuO NWs)/CC and CuO nanoparticles (CuO NPs)/CC, respectively. Ascribing to high conductivity of CC, high specific surface-area from CuO nanostructures, and facilitated charge transfer through in-situ grown structure, the electrodes demonstrate ultrasensitive, selective, stable and fast amperometric sensing (<3 s) of glucose, which presents a new strategy to develop non-enzymatic glucose sensors.

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