Ti_(0.096)V_(0.864)Fe_(0.04)合金的储氢性能研究与物相分析  

Study on the hydrogen storage characteristics and phase structures of Ti_(0.096)V_(0.864)Fe_(0.04) alloy

作　　者：郑坊平[1] 陈立新[1] 李露[1] 王新华[1] 陈长聘[1] 

机构地区：[1]浙江大学材化学院,浙江杭州310027

出　　处：《功能材料》2006年第2期243-246,共4页Journal of Functional Materials

基　　金：国家高技术研究发展计划(863计划)资助项目(2003AA515021);国家自然科学基金资助项目(50271064)

摘　　要：研究了Ti0.096V0.864Fe0.04合金的储氢性能、热力学特性及吸放氢物相变化。研究结果表明,该合金具有较好的吸放氢压力平台特性,合金的20℃最大吸氢量达到3.75%(质量分数),氢化物生成焓变ΔH°为-26.6kJ.(mol H2)-1,熵变ΔS°为-102.5J.(K.mol H2)-1。合金颗粒度、吸放氢循环次数对合金的吸氢速度都有较大影响。该合金具有较好的抗粉化能力,经过10次吸放氢循环后合金粉的平均粒径比吸氢前仅减小约1/5。XRD及SEM分析表明,合金未吸氢前是由单一的体心立方(BCC)结构的钒基固溶体相组成;4MPa下吸氢后生成大量面心立方(FCC)结构的Ti0.096V0.864Fe0.04H2.01和少量体心四方(BCT)结构的Ti0.096V0.864Fe0.04H0.81两种氢化物相;50℃下对0.001MPa放氢后,合金中除Ti0.096V0.864Fe0.04基BCC固溶体相外,还存在Ti0.096V0.864Fe0.04H0.81氢化物相。The hydrogen storage characteristics, thermodynamics and phase structures of Ti0.096V0.864Fe0.04 alloy were investigated systematically. The results show that the alloy has a good hydrogen absorption/desorption pressure plateau characteristics at room temperature, the maximum hydrogen absorption capacity was 3.75wt at 20℃. The thermodynamic parameters for the hydrogenation reaction of Ti0.096V0.864Fe0.04 are ΔH°=- 26.6kJ · （mol H2）^-1 and ΔS°=-102.5J · （K · mol H2）^-1. The grain size of the alloy and cycling number of hydrogen absorption/desorption affect the rate of hydrogen absorption strongly. The alloy has a good anti-pulverization behavior and the average grain size just decreases 20 percent after 10 cycles of hydrogen absorption/desorption. The XRD and SEM analysis show that the alloy consists of a single vanadium-based solid solution phase with BCC structure, and two hydrides of Ti0.096V0.864Fe0.04 H2 with FCC structure and Ti0.096V0.864Fe0.04 H1 with BCT structure form after hydrogenation.

关 键 词：储氢合金 相结构 钒基固溶体 储氢特性 热力学性能 

分 类 号：TG139.7[一般工业技术—材料科学与工程]