ABSTRACT

The ZnO@NiCo-LDH core-shell nanostructures on carbon cloth (CC) are synthesised by a combination of hydrothermal and electrochemical deposition method. The effects of deposition times on the morphology, structure and electrochemical properties of the product are studied. The results show that deposition times at 300 s NiCo-LDH sheets are anchored onto the surface of ZnO NRs, forming a three-dimensional (3D) interconnected thin-walled network structure. ZnO@NiCo-LDH300s electrode shows excellent electrochemical performance, such as areal capacitance of 667.3 mF cm⁻² at 1 mA cm⁻², and good cycle stability (86.78% capacitance retention after 2000 cycles), which may be attributed to the larger contact area and rich active sites between electrode provided by the NiCo-LDH grown on ZnO NRs. Furthermore, the asymmetric supercapacitor (ASC) is assembled with the ZnO@NiCo-LDH300s and active carbon (AC) as the electrodes, which exhibits an energy density of 0.044 mWh cm⁻² at 1.17 mW cm⁻².

摘要

碳布（CC）上的ZnO@NiCo-LDH核壳纳米结构是通过水热和电化学沉积法相结合的方法合成的。研究了沉积时间对产物形貌、结构和电化学性能的影响。结果表明，300 s NiCo-LDH 片材的沉积时间锚定在 ZnO NRs 表面，形成三维 (3D) 互连薄壁网络结构。ZnO@NiCo-LDH300s 电极表现出优异的电化学性能，例如在 1 mA cm ^{-2时的面积电容为 667.3 mF cm -2}，以及良好的循环稳定性（2000 次循环后电容保持率 86.78%），这可能是由于在 ZnO NR 上生长的 NiCo-LDH 提供的电极之间更大的接触面积和丰富的活性位点。此外，不对称超级电容器（ASC）由ZnO@NiCo-LDH300s和活性炭（AC）作为电极组装而成，其在1.17 mW cm ^{-2时的能量密度为0.044 mWh cm -2}。