Xie Yiming, Yin Jie, Zheng Juanjuan, Wang Lingjie, Wu Jihuai, Dresselhaus Mildred, Zhang Xingcai
Engineering Research Center of Environment-Friendly Functional Materials, Ministry of Education, Institute of Materials Physical Chemistry , Huaqiao University , Xiamen 361021 , China.
John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States.
ACS Appl Mater Interfaces. 2019 Sep 4;11(35):32244-32250. doi: 10.1021/acsami.9b06934. Epub 2019 Aug 22.
The preparation of green, facile, and cost-effective energy storage materials remains a big challenge. In this paper, a cobalt sulfide/porous carbon (CoS/PC) composite electrode is facilely prepared using the natural eggshell membrane (ESM) as a basal substrate. Under hydrothermal conditions, CoS is grown on the ESM to form CoS/ESM and carbonized to form CoS/PC. The as-synthesized CoS/PC composite is used as an electrode material. The carbide from the ESM shows a porous structure and high specific surface area, which provides large space for CoS attaching and ion migrating. CoS/PC shows much higher specific capacitance values than the sum of CoS and PC electrodes, indicating a significant synergistic effect. More importantly, the CoS is a typical faradic material, which exchanges Faraday charge with an electrolyte and subsequently transmits an electron to the whole electrode due to the high conductivity of the carbonized ESM. Such a synergistic effect offers the as-synthesized CoS/PC electrode a significant improvement in performance over both the ESM-derived carbon and the original CoS. Besides, the CoS/PC electrode shows a wide potential window, low resistance, and high specific capacitance. After 1000 cycles, the electrode retains a high cycling capacity. This study provides a novel insight for high-performance biomass-derived carbon preparation for pseudocapacitors and other electrochemical devices.
制备绿色、简便且具有成本效益的储能材料仍然是一项巨大挑战。本文以天然蛋壳膜（ESM）为基础基底，简便地制备了硫化钴/多孔碳（CoS/PC）复合电极。在水热条件下，CoS在ESM上生长形成CoS/ESM，然后碳化形成CoS/PC。所合成的CoS/PC复合材料用作电极材料。来自ESM的碳化物呈现出多孔结构和高比表面积，为CoS附着和离子迁移提供了较大空间。CoS/PC的比电容值远高于CoS电极和PC电极之和，表明存在显著的协同效应。更重要的是，CoS是一种典型的法拉第材料，它与电解质交换法拉第电荷，随后由于碳化ESM的高导电性将电子传输到整个电极。这种协同效应使所合成的CoS/PC电极在性能上比源自ESM的碳和原始CoS都有显著提升。此外，CoS/PC电极具有宽电位窗口、低电阻和高比电容。经过1000次循环后，该电极仍保持高循环容量。本研究为用于赝电容器和其他电化学器件的高性能生物质衍生碳的制备提供了新的见解。
