摘要
为了解Pr取代La对La-Mg-Ni系(AB3.5型)储氢合金性能的影响,研究了La0.65-xPrxNd0.12Mg0.23Ni3.4Al0.1(x=0.0,0.1和0.2)储氢合金的电化学性能,重点考察了其电化学动力学特性。试验表明,Pr取代La使合金的储氢容量有所降低,但循环稳定性没有明显的变化。Pr取代La对合金的电化学动力学性能产生了明显的影响,随Pr的添加,合金电极在放电电流密度为1800mA.g-1的高倍率放电能力(HRD)从26.0%(x=0.0)显著地增加到60.0%(x=0.1),然后缓慢减小到55.8%(x=0.2)。电化学阻抗谱、线性极化曲线、阳极极化曲线及氢扩散系数测量结果均表明,合金中添加Pr改善了合金电极的电化学动力学特性。
In order to research the effect of the substitution of Pr for La on the electrochemical properties of the La-Mg-Ni （ AB3.5-type ） hydrogen storage alloy, the electrochemical properties of the La0.65-x Prx Nd0.12 Mg0.23Ni3.4Al0. 1 （x =0.0, 0.1,0.2） hydrogen storage alloys were investigated. The electrochemical testing showed that the substitution of Pr for La mildly decreased the hydrogen storage life of the alloys. However, ability （HRD） of the alloy capacity and the cycling the high-rate discharge- electrodes remarkably in-creased from 26.0% （x =0.0） to 60.0% （x = 0.1）, and then slowly decreased to 55. 8% （x = 0.2） at the high discharge current density of 1800 mA.g^-1. Meanwhile, the results from the electrochemical impedance spectroscopy, linear polarization, anode polarization, and hydrogen diffusion coefficient measurements indicated that the electrochemical kinetic properties of the alloy electrodes were improved by the addition of Pr in the present alloys.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2009年第3期423-429,共7页
Journal of the Chinese Society of Rare Earths
基金
国际科技合作项目(2006DFB52550)
国家自然科学基金项目(20363001)资助
关键词
稀土系储氢合金
AB3.5型储氢合金
金属氢化物电极
电化学性能
电化学动力学
rare earth based-hydrogen storage alloy
AB3.5-type hydrogen storage alloy
MH electrode
electrochemical properties
electrochemical kinetic property
