A novel hierarchical 3D core-shell material [NF@NiCo₂O₄ @NiCoMn(OH)] were fabricated for supercapacitors, in which the ultrathin NiCoMn(OH) nanosheets were coated on the NiCo₂O₄ nanoarray supported on Ni foam. At the optimal Co-doping (Co/Ni molar ratio = 1: 5 at (Co+Ni)/Mn molar ratio of 4.0), the NiCoMn(OH)_1/5 had better rate capability and higher specific capacitance than the NiMn(OH) precursor, which improved the electrochemical properties. To further enhance the electrochemical performance, the NF@NiCo₂O₄ @NiCoMn(OH) core-shell material was designed and prepared, which exhibited a much higher specific capacitance of 2300 F·g⁻¹ than the NiCoMn(OH)_1/5 (1417 F·g⁻¹) at 1 A∙g⁻¹ and 87.7% retention at 5 A∙g⁻¹ for 2 000 cycles. The excellent capacitive properties were ascribed to the unique 3D hierarchical structure and strong synergistic effect between the ultrathin NiCoMn(OH) nanosheets shell and NF@NiCo₂O₄ nanoarray core. As a result of the asymmetric supercapacitor, the NiCo₂O₄ @NiCoMn(OH)//AC device showed a remarkably high energy density (61.3 Wh∙kg⁻¹) at a power density of 850 W∙kg⁻¹. The strategy can be extended to other core-shell electrode material toward energy storage applications.

为超级电容器制造了一种新型的分层 3D 核壳材料 [NF@ NiCo ₂ O ₄ @NiCoMn(OH)]，其中超薄 NiCoMn(OH) 纳米片被涂覆在 NiCo ₂ O ₄纳米阵列上，该纳米阵列支撑在泡沫镍上。在最佳共掺杂条件下（Co/Ni 摩尔比 = 1:5，(Co+Ni)/Mn 摩尔比为 4.0），NiCoMn(OH) _1/5比 NiMn( OH) 前驱体，提高了电化学性能。为了进一步提高电化学性能，我们设计并制备了NF@ NiCo ₂ O ₄ @NiCoMn(OH)核壳材料，其比电容高达2300 F·g ^-1比 NiCoMn(OH) _1/5 (1417 F·g ^-1 ) 在 1 A∙g ^-1和 87.7% 在 5 A∙g ^-1循环 2 000 循环。优异的电容特性归因于独特的3D层次结构和超薄NiCoMn(OH)纳米片壳与NF@NiCo ₂ O ₄纳米阵列核之间的强协同效应。由于采用了不对称超级电容器， NiCo ₂ O ₄ @NiCoMn(OH)//AC 器件在 850 W∙kg ^-1的功率密度下表现出非常高的能量密度（61.3 Wh∙kg ^-1 ） 。该策略可以扩展到其他核壳电极材料的储能应用。