The energy storage device has been urgently studied and developed to meet the increasing demand for energy and sustainable development. Due to the excellent conductivity of graphene and high performance of ZnCo₂O₄ and NiCo₂O₄, we design a self-supporting electrode based on vertically grown two-dimensional/two-dimensional (2D/2D) NiCo₂O₄/ZnCo₂O₄ hierarchical flakes on the carbon-based conductive substrate (NiCo₂O₄/ZnCo₂O₄@graphene/carbon nanotubes, NZ@GC). The density functional theory calculations indicate that the high OH⁻ adsorption capacity of the NiCo₂O₄/ZnCo₂O₄ nanosheets can significantly enhance the electrochemical reaction activity. NZ@GC shows a high capacitance of 1128.6 F g⁻¹ at 1 A g⁻¹. The capacitance retains 84.0% after 6000 cycles even at 10 A g⁻¹. A hybrid supercapacitor is fabricated using NZ@GC and activated carbon, exhibiting a large energy density of 50.8 W h kg⁻¹ at the power density of 800 W kg⁻¹. After 9000 charge/discharge cycles, the supercapacitor still has 86.1% capacitance retention. The NZ@GC film has showed the potential as promising electrodes in high efficiency electrochemical energy storage devices.

为了满足日益增长的能源需求和可持续发展的需求，储能装置得到了迫切的研究和开发。由于石墨烯的优异导电性和 ZnCo ₂ O ₄和NiCo ₂ O ₄的高性能，我们设计了一种基于垂直生长的二维/二维（2D/2D）NiCo ₂ O ₄ /ZnCo的自支撑电极。碳基导电基板上的₂ O _{4分级薄片（NiCo 2} O ₄ /ZnCo ₂ O ₄ @石墨烯/碳纳米管，NZ@GC）。密度泛函理论计算表明，高 OH^{− NiCo} ₂ O ₄ /ZnCo ₂ O ₄纳米片的吸附能力可以显着提高电化学反应活性。NZ@GC在 1 A g ^-1下显示出 1128.6 F g ^-1的高电容。即使在 10 A g ^-1下，电容在 6000 次循环后仍保持 84.0% 。使用 NZ@GC 和活性炭制造混合超级电容器，在 800 W kg ^{-1的功率密度下表现出 50.8 W h kg -1的大能量密度}. 经过 9000 次充电/放电循环后，超级电容器仍有 86.1% 的电容保持率。NZ@GC 薄膜在高效电化学储能装置中显示出作为有前途的电极的潜力。