College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, 030024, P.R. China.
Shanxi Key Laboratory of New Energy Materials and Devices, Taiyuan University of Technology, Taiyuan, 030024, P.R. China.
Chemistry. 2020 Jan 13;26(3):650-658. doi: 10.1002/chem.201902859. Epub 2019 Oct 24.
Zinc-cobalt double-metal sulfides (ZCS) as Faradic electrode materials with high energy density have great potential for supercapacitors, but their poor transfer efficiency for electrons and ions hinders their electrochemical response. Herein, ZnCo (CO ) (OH) @ZCS microflower hybrid arrays consisting of thin nanolayer petals were anchored on three-dimensional graphene (ZnCo (CO ) (OH) @ZCS/3DG) by a simple hydrothermal method and additional ion-exchange process. A ZnCo (CO ) (OH) @ZCS/3DG electrode delivered high capacitance (2228 F g at 1 A g ) and long cycling life (85.7 % retention after 17 000 cycles), which are ascribed to the multicomponent structural design. The 3DG conductive substrate improves the electron-transfer dynamics of the electrode material. Meanwhile, the microflowers consisting of thin nanolayer petals could not only provide many active sites for ions to improve the capacitance, but also alleviate the volume expansion to ensure the structural stability. Furthermore, an all-solid-state asymmetric supercapacitor based on a ZnCo (CO ) (OH) @ZCS/3DG electrode achieved a high energy density of 27 W h kg at 528.3 W kg and exhibits exceptional cyclic stability for 23 000 cycles. Its ability to light a blue LED for 9 min verified the feasibility of its application for energy storage devices.
锌钴双金属硫化物（ZCS）作为具有高能量密度的法拉第电极材料，在超级电容器方面具有巨大的潜力，但它们电子和离子传输效率差，阻碍了其电化学响应。在此，通过简单的水热法和额外的离子交换过程，将由薄纳米层花瓣组成的 ZnCo（CO）（OH）@ZCS 微花杂化阵列锚定在三维石墨烯（ZnCo（CO）（OH）@ZCS/3DG）上。ZnCo（CO）（OH）@ZCS/3DG 电极具有高电容（在 1 A g 下为 2228 F g）和长循环寿命（在 17000 次循环后保持 85.7%），这归因于多组分结构设计。3DG 导电基底改善了电极材料的电子转移动力学。同时，由薄纳米层花瓣组成的微花不仅可以提供许多离子的活性位点以提高电容，还可以缓解体积膨胀以确保结构稳定性。此外，基于 ZnCo（CO）（OH）@ZCS/3DG 电极的全固态不对称超级电容器实现了 27 W h kg 的高能量密度，在 528.3 W kg 时具有出色的循环稳定性，循环 23000 次后仍保持稳定。其为一个蓝色 LED 供电 9 分钟的能力验证了其在储能设备中应用的可行性。
