Zhou Jiachao, Wang Yingchao, Chen Linli, Zhao Wenna, Han Lei
State Key Laboratory Base of Novel Functional Materials and Preparation Science, School of Materials Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China.
School of Biological and Chemical Engineering, Ningbotech University, Ningbo, Zhejiang 315100, China.
Dalton Trans. 2023 Sep 19;52(36):12978-12987. doi: 10.1039/d3dt01991h.
Layered double hydroxides (LDHs) and metal sulfides (MSs) have been widely used as promising electrode materials for supercapacitors, and the rational architectural design of MS/LDH heterogeneous structures is critical to optimize large energy storage. Herein, a precisely designed hollow CoS nanotubes@CoNi-LDH nanosheet heterostructure on Ni foam, facilely prepared by an ingenious strategy in this CoS nanoarray was first used as the self-sacrificing template and metal source to synthesize Co-ZIF-67 polyhedron to form the CoS@ZIF-67 heterostructure, and then CoS@ZIF-67 was etched successfully using Ni ions to form the final CoS@CoNi-LDH/NF core-shell nanoarray. This synthetic strategy to fabricate the heterostructure is conducive to boosting the structural stability, modifying the electric structure and regulating the interfacial charge transfer. Due to the synergistic effect and tight heterogeneous interface, CoS@CoNi-LDH/NF displayed an outstanding capacitance of 9.65 F cm at a current density of 2 mA cm and excellent capacitance retention rate of 91.7% after 5000 cycles. In addition, the ASC device assembled with AC has an extremely high energy density of 1.0 mW h cm at 2 mA cm and maintains 96.9% capacitance retention after 5000 cycles. This work provides a skillful strategy for the precise design and synthesis of MS/LDH heterostructures with fascinating features for electrochemical energy storage applications.
层状双氢氧化物（LDHs）和金属硫化物（MSs）作为超级电容器极具潜力的电极材料已被广泛应用，而MS/LDH异质结构的合理架构设计对于优化大容量储能至关重要。在此，通过一种巧妙的策略在泡沫镍上精确设计并轻松制备了一种中空的CoS纳米管@CoNi-LDH纳米片异质结构，该CoS纳米阵列首先用作自牺牲模板和金属源来合成Co-ZIF-67多面体以形成CoS@ZIF-67异质结构，然后使用镍离子成功蚀刻CoS@ZIF-67以形成最终的CoS@CoNi-LDH/NF核壳纳米阵列。这种制备异质结构的合成策略有利于提高结构稳定性、修饰电子结构并调节界面电荷转移。由于协同效应和紧密的异质界面，CoS@CoNi-LDH/NF在2 mA cm的电流密度下显示出9.65 F cm的出色电容，并且在5000次循环后具有91.7%的优异电容保持率。此外，与活性炭组装的不对称超级电容器（ASC）器件在2 mA cm下具有1.0 mW h cm的极高能量密度，并且在5000次循环后保持96.9%的电容保持率。这项工作为精确设计和合成具有迷人特性的MS/LDH异质结构以用于电化学储能应用提供了一种巧妙的策略。
