机械合金化法制备非晶Nb60TM40-MgH2(TM=Ni,Fe)复合储氢材料的吸放氢性能

Hydrogen Storage Properties of Amorphous Nb 60 TM 40-MgH 2(TM=Ni,Fe)Composites Prepared by Mechanical Alloying

采用机械合金化法制备了Nb60Ni40及Nb60Fe40非晶合金,再通过球磨法向MgH2中分别掺杂10%上述非晶,并利用XRD、SEM、P-C-T、DSC等分析测试手段对样品的微观结构及吸放氢性能进行了表征。XRD结果表明,通过机械合金化法得到了Nb-Ni和Nb-Fe非晶。SEM观察显示,掺杂非晶后,MgH2粉末颗粒得到了细化。P-C-T测试结果表明,非晶Nb60Ni40及Nb60Fe40的掺杂未改善MgH2的吸放氢热力学性能,但非晶Nb60Ni40-MgH2及非晶Nb60Fe40-MgH2复合粉体的吸氢速率有一定的提升;放氢动力学测试表明,非晶掺杂加快了MgH2的放氢速率,350℃下10min即可实现完全放氢。DSC测试结果显示,非晶Nb60Ni40-MgH2体系和非晶Nb60Fe40-MgH2体系的放氢激活能分别为146.14和145.65kJ/mol,与纯MgH2相比分别降低了22.68和23.17kJ/mol。

In the research,amorphous alloys including Nb 60 Ni 40 and Nb 60 Fe 40 were synthesized by mechanical alloying,and were doped into MgH 2 with 10%through ball milling.XRD,SEM,P-C-T,and DSC tests were carried out to investigate microstructure and hydrogen storage properties of the composites.XRD patterns indicated that Nb-Ni and Nb-Fe powders were obtained from mechanical alloying in amorphous state.SEM observations showed that the size of MgH 2 particles were refined after doping with amorphous.The addition of amorphous alloys Nb 60 Ni 40 and Nb 60 Fe 40 did not change thermodynamic properties but enhanced the hydrogenation kinetics of Mg.With the addition of amorphous Nb 60 Ni 40 and Nb 60 Fe 40,the dehydriding activation energy of MgH 2 was reduced to 146.14 and 145.65 kJ/mol,about 22.68 and 23.17 kJ/mol lower than that of the pure MgH 2,respectively.Besides,full dehydrogenation can be achieved within 10 mins at 350℃.