摘要
用机械合金化法制备了Mn15Bi34Te51和La15Bi34Te51合金,XRD分析表明Mn15Bi34Te51和La15Bi34Te51分别在真空球磨150h和100h后实现合金化,La15Bi34Te51在真空球磨150h后形成了纳米结构的合金,镧原子的加入有助于Bi2Te3基合金的晶粒细化及非晶化。对La15Bi34Te51合金的XRD结构分析表明镧原子有可能进入了Bi2Te3层状结构的Te-Te原子层间。La15Bi34Te51合金Seebeck系数的测量表明当晶粒尺寸减小到纳米尺寸时,载流子散射机制有可能发生改变,导致了Seebeck系数的大幅上升。
According to XRD the alloys Mn15Bi34Te51 and La15Bi34Te51 were formed after ball milling for 150 h and 100 h, respectively. Nanostructured La15Bi34Te51 resulted from extending the ball milling time to 150 h, It is suggested that the addition of La may refine the grain size and help to promote amorphism in Bi2Te3 based alloys. Further detailed XRD analysis of La15Bi34Te51 alloys suggests that the La atoms may intercalate between the Te Te layers of the Bi2Te3 layer structure. The Seeback coefficient measurements on the La15Bi34Te51 alloys indicates that the carrier scattering mechanism changes when the grain sizes are decreased to a few nanometers leading to a dramatic increase in the Seeback coefficient.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2002年第4期287-290,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金资助项目(59971044)
教育部博士点基金资助项目(97033518)
