【摘要】 通过一步水热的方法在泡沫镍（NF）基底上生长了镍钴层状双金属氢氧化物（NiCo-LDHs）阵列。研究了Ni和Co的物质的量比对其晶相结构、形貌和电容性能的影响。在n（Ni）∶n（Co）=2∶2时获得高电容量和高循环稳定性的Ni₂Co₂-LDH有序致密的多孔纳米针阵列。在电流密度1 A·g^-1时，比电容高达2 381 F·g^-1;在电流密度10 A·g^-1时，电容率保持率为57.1%;4 500次充放电循环后电容率保持高达60%。最后，以Ni₂Co₂-LDH@NF为正极，以活性炭为负极构建了非对称电容器。在电流密度为1 A·g^-1时，该非对称电容器的比容量为211.4 F·g^-1。在电流密度5 A·g^-1时，5 000次充放电循环后电容保持率高达90%。在11.6 kW·kg^-1的功率密度下拥有73.1 Wh·kg^-1的能量密度。更多还原

【Abstract】 In this paper, nickel-cobalt layered double hydroxides（NiCo-LDHs） were synthesized on nickel foam（NF） by one-step hydrothermal method. The effects the molar ratio Ni and CO on the crystal structure, morphology and capacitive properties were studied. When n（Ni）∶n（Co）=2∶2,ordered and dense porous Ni₂Co₂-LDHs nanoneedle arrays with high capacitance and high cycle stability were obtained. The specific capacitance is 2 381 F·g^-1 at 1 A·g^-1, the capacitance retention rate is 57.1% at 10 A·g^-1 and 60% after 4 500 charge discharge cycles, respectively. Finally, an asymmetric supercapacitor was constructed with Ni₂Co₂-LDH@NF as the positive electrode material and commercial activated carbon as the negative electrode material. The specific capacitance is 211.4 F·g^-1 at 1 A·g^-1, the capacitance retention rate is 90% after 5 000 charge-discharge cycles at 5 A·g^-1. It has an energy density of 73.1 kW·kg^-1 at a power density of 11.6 kW·kg^-1.更多还原