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用真空电弧熔炼方法制备了Zr1-xScxMn0.6V0.2Ni1.2Co0.1(x=0～1)AB2型储氢合金,研究了Sc元素替代Zr对合金的微观组织结构、气态储氢及电化学性能的影响。研究结果表明,Zr1-xScxMn0.6V0.2Ni1.2Co0.1合金主要是由FCC型C15相、CsCl型结构的(ScZr)Ni相和少量的Ni10Zr7相组成,随Sc含量的增加,C15相丰度逐渐减小,(ScZr)Ni相丰度逐渐增加,当x=0.2时Ni10Zr7相基本消失;Sc元素对合金的首次气态吸氢动力学行为影响较大,随Sc含量的增加,合金吸氢动力学性能逐渐变缓,但吸氢容量逐渐提高,直至达x=1.0时的最大吸氢量1.87%;Sc元素对合金吸氢PCT曲线平衡氢压的影响规律不明显,随Sc含量增加,合金氢化物的形成焓ΔH从-26.66 kJ.mol-1逐渐减小到-8.14 kJ.mol-1。Sc元素的加入可明显改善合金电极的活化性能,提高放电容量,随Sc含量的增加,合金电极最大放电容量从x=0时的350.3 mAh.g-1增加到x=1时的429.8 mAh.g-1,呈先减小后增大的趋势,但电极容量的保持率S100随Sc含量增加而快速下降。
Zr1-xScxMn0.6V0.2Ni1.2Co0.1 (x = 0 ~ 1) AB2 hydrogen storage alloys were prepared by vacuum arc melting method. The effects of Sc element substitution Zr on the microstructure, gas storage hydrogen and electrochemical The impact of performance. The results show that the Zr1-xScxMn0.6V0.2Ni1.2Co0.1 alloy is mainly composed of FCC type C15 phase, CsCl type (ScZr) Ni phase and a small amount of Ni10Zr7 phase. With the increase of Sc content, the C15 phase abundance (ScZr) Ni phase abundance gradually increased, Ni10Zr7 phase basically disappeared when x = 0.2; Sc element on the kinetics of the first gaseous hydrogen absorption kinetics greatly affected, with the increase of Sc content, the alloy hydrogen absorption power The hydrogen absorption capacity gradually increased until the maximum hydrogen absorption rate of 1.87% when x = 1.0. The effect of Sc on hydrogen balance pressure of PCT hydrogen absorption curve was not obvious. With the increase of Sc content, Hydride formation enthalpy ΔH decreased from -26.66 kJ · mol-1 to -8.14 kJ · mol-1. The addition of Sc can obviously improve the activation performance of the alloy electrode and increase the discharge capacity. With the increase of Sc content, the maximum discharge capacity of the alloy electrode increases from 350.3 mAh.g-1 at x = 0 to 429.8 mAh at x = 1. g-1, first decreased and then increased, but the retention of electrode capacity S100 decreased rapidly with the increase of Sc content.