Mg-Ni非晶合金吸氢形成焓随Ni含量的变化及其对自放电的影响
来源期刊:中国有色金属学报2000年第6期
论文作者:张耀 孙俊才 季世军 雷永泉 王启东
文章页码:882 - 886
关键词:Mg-Ni非晶合金; 吸氢形成焓;自放电特性
Key words:Mg-Ni amorphous alloys; hydrogen absorption enthalpy; self-discharge property
摘 要:通过电化学实验方法以及Miedema理论模型计算分别获得了Mg-Ni非晶合金的吸氢形成焓ΔH,两者对比较为接近,说明该模型可被用于估算非晶合金的吸氢形成焓。对形成焓随Ni含量的变化趋势进行了研究,结果表明,当Ni含量(摩尔分数)高于55%时,合金吸氢稳定性随Ni含量的增加而升高;而当Ni含量低于55%时,稳定性的改变恰好相反。此外还分析了这种变化趋势对MgNi非晶合金电极的自放电特性的影响,结果表明,吸氢形成焓越负的合金,其自放电效应越弱。
Abstract: The hydrogen absorption enthalpies of Mg-Ni amorphous alloys were determined by means of electrochemical test and compared with those obtained by mathematical evaluation according to Miedema's model. The values werefound agreed well. The result demonstrates that the model can be used in theevaluation of the hydrogen absorption enthalpies of amorphous alloys. Through investigating the enthalpies varied with Ni content, it can be concluded that thealloys hydrogen absorption stability increases with the Ni content increasing when Ni content(mole fraction) is higher than 55%, and the change is on the contrary when Ni content(mole fraction) is less than 55%. The effect of Ni content on the selfdischarge properties of amorphous Mg-Ni electrodes was also examined. The result shows that the more negative the ΔH value is, the less the selfdischarge.