物理化学学报2020，Vol.36Issue(7)：31-39,9.DOI:10.3866/PKU.WHXB201907072
用于超级电容器的锰钴氧化物/碳纤维材料
MnCo Oxides Supported on Carbon Fibers for High-Performance Supercapacitors
摘要
Abstract
The development of high-performance supercapacitor electrode materials is imperative to alleviate the ongoing energy crisis. Numerous transition metals (oxides) have been studied as electrode materials for supercapacitors owing to their low cost, environmental-friendliness, and excellent electrochemical performance. Among the developed binary transition metal oxides, manganese cobalt oxides typically show high theoretical capacitance and stable electrochemical performance, and are widely used in the electrode materials of supercapacitors. However, the poor conductivity and active material utilization of manganese cobalt oxide-based electrode materials limit their potential capacitance application. Cotton is mainly composed of organic carbon-containingmaterials, which can be transformed to carbon fibers after calcination. The resultant carbonaceous material exhibits a large specific surface area and good conductivity. Such advantages could potentially suppress the negative effects caused by the poor conductivity and small specific surface area of manganese cobalt oxides, thereby improving the electrochemical performance. Herein, we firstly deposited manganese cobalt oxides on cotton by a simple hydrothermal method, yielding a composite of manganese cobalt oxides and carbon fibers via subsequent calcination, to improve the electrochemical performance of the electrode material. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA), and electrochemical characterizations were used to investigate the physical, chemical, and electrochemical properties of the prepared samples. The fabricated manganese cobalt oxides in the composite were uniformly dispersed on the carbon fiber surface, which increased the contact between the interface of the electrode material and electrolyte, and enhanced electrode material utilization. The electrode material was confirmed to have well contacted with the electrolyte during a contact angle test. Hence, a pseudo-capacitance reaction completely occurred on the manganese cobalt oxide material. Moreover, the addition of carbon fibers reduced the resistance of the material, resulting in excellent capacitive performance. The capacitance of the prepared composite was 854 F·g?1 at a current density of 2 A·g?1. The capacitance was maintained at 72.3％ after 2000 cycles at a current density of 2 A·g?1. These results indicate that the manganese cobalt oxide and carbon fiber composite is a promising electrode material for high-performance supercapacitors. The findings presented herein provide a strategy for coupling with carbon materials to enhance the performance of supercapacitor electrode materials based on manganese cobalt oxides. Thus, novel insights into the design of high-performance supercapacitors for energy management are provided.关键词
锰钴氧化物/碳纤维/超级电容器/复合材料/接触Key words
Manganese cobalt oxide/Carbon fiber/Supercapacitor/Composite/Contact分类
化学化工引用本文复制引用
王玖,吴南石,刘涛,曹少文,余家国..用于超级电容器的锰钴氧化物/碳纤维材料[J].物理化学学报,2020,36(7):31-39,9.基金项目
The project was supported by the National Natural Science Foundation of China (51922081, 21773179, U1705251, 21433007), the Natural Science Foundation of Hubei Province, China (2017CFA031), and the Fundamental Research Funds for the Central Universities, China (WUT: 2019-Ⅲ-196).国家自然科学基金(51922081, 21773179, U1705251, 21433007), 湖北自然科学基金(2017CFA031)和中央高校本科研业务费专项基金(WUT: 2019-Ⅲ-196)资助项目 （51922081, 21773179, U1705251, 21433007）
