Interlayer Spacing Regulation of NiCo-LDH Nanosheets with Ultrahigh Specific Capacity for Battery-Type Supercapacitors.
Interlayer Spacing Regulation of NiCo-LDH Nanosheets with Ultrahigh Specific Capacity for Battery-Type Supercapacitors.
复制标题
DOI：
10.1021/acsami.1c19320
复制
发表时间：
2021-11
影响因子：
9.5
通讯作者：
Qianfeng Pan;F. Zheng;Dingfei Deng;Bo Chen;Yang Wang
中科院分区：
文献类型：
--
作者：
Qianfeng Pan;F. Zheng;Dingfei Deng;Bo Chen;Yang Wang
过渡金属层状双金属氢氧化物（LDHs）由于其优异的电化学活性和可调的化学组成，作为一种新型的功能纳米材料得到了广泛的研究。本文以醋酸根（Ac-）为插层元素，采用简单的水热法制备了不同插层量和水热溶液体积的NiCo-LDH纳米片阵列。最佳的Ac-阴离子用量使LDH纳米片的层间距从0.8 nm扩大到0.94 nm.在1Ag ~（-1）时的比容量为1200 Cg ~（-1）（不含Ac ~（-1）时为690 Cg ~（-1）），在30 Ag ~（-1）时的倍率性能为72.5%，循环4500次后的循环稳定性为79.90%，这主要归因于较高的Ac ~（-1）层间距。层间距的增大有利于LDHs α相的稳定，促进电化学反应中电子传递和电解质渗透。该研究揭示了NiCo-LDH纳米片层间距调控的机理，并为通过整合其独特的层状结构和层间阴离子交换特性来合成具有优异电化学性能的功能纳米材料提供了一种有前途的策略。
The transition metal-based layered double hydroxides (LDHs) have been extensively studied as promising functional nanomaterials owing to their excellent electrochemical activity and tunable chemical composition. In this work, using acetate anions (Ac-) as intercalating elements, the NiCo-LDH nanosheets arraying on Ni foam with different amounts of Ac- anion intercalation or volume of hydrothermal solution were prepared by a simple hydrothermal method. The optimized amount of Ac- anions expanded the interlayer space of LDH nanosheets from 0.8 to 0.94 nm. An ultrahigh specific capacity of 1200 C g-1 at 1 A g-1 (690 C g-1 without Ac- anions), an outstanding rate capability of 72.5% at 30 A g-1, and a cycle stability of 79.90% after 4500 cycles were mainly attributed to the higher interlayer spacing of Ac- anion intercalation. The enlarged interlayer spacing was beneficial for stabilizing the α-phase of LDHs and accelerating the electron transport and electrolyte penetration in the electrochemical reaction. This work sheds light on the mechanisms of the interlayer spacing regulation of NiCo-LDH nanosheets and offers a promising strategy to synthesize functional nanomaterials with excellent electrochemical performance via integrating their unique layered structure and interlayer anion exchange characteristics.