碳纤维负载Co纳米颗粒对Co9S8储氢性能的影响-中国材料进展

文章信息/Info

Title:: Effect of Carbon Fiber Supported Cobalt Nanoparticles on the Hydrogen Storage Properties of Co9S8

Author(s):: LIU Heng; LIU Wanqiang; (School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130012, China)

Keywords:: hydrogen storage; cobalt/carbon nanofiber; electrochemistry; composite material; Co9S8

摘要:: 钴硫合金作为镍氢电池负极的优良材料在新能源领域受到广泛关注。然而在充放电过程中由于颗粒聚集和体积变化等问题导致电化学性能不尽人意，限制了其实际应用。开发出一种电化学性能优异、成本低廉、制备工艺简单的钴硫复合材料具有十分重要的研究意义和应用价值。以Co9S8为研究对象，采用静电纺丝工艺制备了负载不同含量Co纳米颗粒的碳纳米纤维(xCo/CNF)，之后通过高能球磨法将该材料掺杂到Co9S8合金中，得到一系列Co9S8+xCo/CNF复合材料。通过X射线衍射仪、场发射扫描电子显微镜对材料的物相和表面微观形貌进行表征，并对复合材料的放电容量、电化学性能、动力学性能以及耐腐蚀性进行测试。研究结果表明，当添加Co9S8+1.2Co/CNF时，所得复合材料的放电容量最高(566.2 mAh·g-1)，此外，复合电极表现出优异的高倍率放电能力、耐腐蚀性和良好的动力学性能。

Abstract:: Cobalt-sulfur alloy has been widely concerned in the field of new energy as an excellent anode material of nickel metal hydride (Ni-MH) batteries. However, the electrochemical performance is adversely affected by particles aggregation and volume change during the charging and discharging process, which limits its practical application. It is of great significance to develop a cobalt-sulfur composite with excellent electrochemical performance, low cost and simple preparation process. In this paper, Co9S8 was taken as the research object. Carbon nanofibers loaded with cobalt nanoparticles of different contents (xCo/CNF) were prepared by electrospinning and annealing process, and then being doped into Co9S8 alloy by high energy-ball milling method to obtain a series of Co9S8+xCo/CNF composites. The phases and surface morphologies of the composite materials were characterized by X-ray diffractometry (XRD) and field emission scanning electron microscopy (SEM), and the discharge capacity, electrochemical performance, kinetic properties and anti-corrosive performance of the composites were tested. The results showed that when the Co9S8+1.2Co/CNF was added, the discharge capacity of the composite was the highest (566.2 mAh·g-1). In addition, the composite electrode showed excellent high rate discharge ability, corrosion resistance and good kinetic properties.