应用化学 ›› 2020, Vol. 37 ›› Issue (5): 579-586.DOI: 10.11944/j.issn.1000-0518.2020.05.190315

• 研究论文 • 上一篇    下一篇

镍钴氢氧化物的制备及其电化学性能

安露露,米杰()   

  1. 太原理工大学,煤科学与技术国家重点实验室 太原 030024
  • 收稿日期:2019-11-25 接受日期:2020-03-11 出版日期:2020-05-01 发布日期:2020-04-29
  • 通讯作者: 米杰
  • 基金资助:
    山西省重大科技专项(MC2015-04)资助

Synthesis of Nickel Cobalt Hydroxide and Its Electrochemical Properties

AN Lulu,MI Jie()   

  1. State Key Laboratory of Coal Science and Technology, Taiyuan University of Technology,Taiyuan 030024,China
  • Received:2019-11-25 Accepted:2020-03-11 Published:2020-05-01 Online:2020-04-29
  • Contact: MI Jie
  • Supported by:
    Supported by the Major Projects of Shanxi Province(No.MC2015-04)

摘要:

采用化学共沉淀法成功制备了片状镍钴氢氧化物,并探究了不同镍钴物质的量比对样品形貌及电化学性能的影响。 通过X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱仪(XPS)及比表面积孔径分析仪(BET)对样品的结构、形貌进行了表征,并利用循环伏安法、恒电流充放电法等对其电化学性能进行了分析。 结果表明,n(Ni):n(Co)=4:1的样品直接用作电极材料时,具有最好的电化学性能:在0.5 A/g的电流密度下拥有1852 F/g的高比容量;电流密度增大20倍时,仍拥有1330 F/g的高比容量。 以镍钴氢氧化物为正极,活性炭为负极组装的非对称式超级电容器在346 W/kg的功率密度下,能量密度达52 Wh/kg,在循环10000圈之后电容保持率为92%。 优异的电化学性能表明,片状镍钴氢氧化物是很有应用潜力的电极材料之一。

关键词: 镍钴氢氧化物, 超级电容器, 循环稳定性

Abstract:

In this work, the flake nickel cobalt hydroxide was successfully prepared by the chemical co-precipitation method, and the effect of nickel to cobalt molar ratios on the morphologies and electrochemical properties were explored. The structures and morphologies of samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscope (XPS) and specific surface area and pore size analyzer (BET). The electrochemical properties were analyzed by cyclic voltammetry, galvanostatic charge/discharge, etc. The results show that when nickel cobalt hydroxide (n(Ni):n(Co)=4:1) is directly used as electrode material, it has a high specific capacitance of 1852 F/g at a current density of 0.5 A/g. When the current density is increased by 20 times, it still has a high specific capacitance of 1330 F/g. The asymmetric supercapacitor is assembled with nickel cobalt hydroxide as the positive electrode material and active carbon as the negative electrode material. The asymmetric cell possesses a high energy density of 52 Wh/kg at a power density of 346 W/kg, and superior cycle stability (the capacitance retention of 92% after 10000 cycles). Excellent electrochemical properties indicate that flake nickel cobalt hydroxide is one of the most promising electrode materials.

Key words: nickel cobalt hydroxide, supercapacitors, cycle stability