Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, PR China.
Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, PR China.
J Colloid Interface Sci. 2023 Sep 15;646:753-762. doi: 10.1016/j.jcis.2023.05.128. Epub 2023 May 20.
A self-supporting composite electrode material with a unique three-dimensional structure was synthesized by in-situ growth of nanoscale NiMnLDH-Co(OH) on a nickel foam substrate via hydrothermal electrodeposition. The 3D layer of NiMnLDH-Co(OH) provided abundant reactive sites for electrochemical reactions, ensuring a solid and conductive skeleton for charge transfer and resulting in significant enhancement of electrochemical performance. The composite material showed a strong synergistic effect between the small nano-sheet Co(OH) and NiMnLDH, which promoted reaction kinetics, while the nickel foam substrate acted as a structural conductivity agent, stabilizer, and good conductive medium. The composite electrode showed impressive electrochemical performance, achieving a specific capacitance of 1870F g at 1 A g and retaining 87% capacitance after 3000 charge-discharge cycles, even at a high current density of 10 A g. Moreover, the resulting NiMnLDH-Co(OH)//AC asymmetric supercapacitor (ASC) demonstrated remarkable specific energy of 58.2 Wh kg at a specific power of 1200 W kg, along with outstanding cycle stability (89% capacitance retention after 5000 cycles at 10 A g). More importantly, DFT calculations reveal that NiMnLDH-Co(OH) facilitates charge transfer, accelerating surface redox reactions and increasing specific capacitance. This study presents a promising approach towards designing and developing advanced electrode materials for high-performance supercapacitors.
通过水热电沉积，在泡沫镍基底上原位生长纳米级 NiMnLDH-Co(OH)，合成了具有独特三维结构的自支撑复合电极材料。3D 层状 NiMnLDH-Co(OH)为电化学反应提供了丰富的反应活性位点，确保了电荷转移的坚固和导电骨架，从而显著提高了电化学性能。该复合材料表现出小纳米片 Co(OH)与 NiMnLDH 之间的强烈协同效应，促进了反应动力学，而泡沫镍基底则起到了结构导电性剂、稳定剂和良好的导电介质的作用。该复合电极表现出令人印象深刻的电化学性能，在 1 A g 下具有 1870 F g 的比电容，在 3000 次充放电循环后仍保留 87%的电容，即使在 10 A g 的高电流密度下也是如此。此外，所得到的 NiMnLDH-Co(OH)//AC 非对称超级电容器 (ASC) 在 1200 W kg 的比功率下具有 58.2 Wh kg 的显著比能量，以及出色的循环稳定性（在 10 A g 下 5000 次循环后电容保持率为 89%）。更重要的是，DFT 计算表明 NiMnLDH-Co(OH)有助于电荷转移，加速表面氧化还原反应并提高比电容。本研究为设计和开发用于高性能超级电容器的先进电极材料提供了一种有前途的方法。
