n型Ge基Ba_8Ga_(16-x)Zn_xGe_(30)Ⅰ-型笼合物的制备及电传输特性  

Synthesis and Electrical Transport Properties of n-type Ge-based Ba_8Ga_(16-x)Zn_xGe_(30) Type-Ⅰ Clathrates

作　　者：邓书康[1] 申兰先[1] 郝瑞亭[1] 田晶[1] 杨培志[1] 

机构地区：[1]云南师范大学教育部可再生能源材料先进技术与制备重点实验室,昆明650092

出　　处：《人工晶体学报》2010年第1期237-241,共5页Journal of Synthetic Crystals

基　　金：国家自然科学青年基金(No.50902119);云南省社会发展基础研究项目(No.2008CD114;2007E197M)

摘　　要：用熔融法结合放电等离子体烧结技术,采用Zn掺杂制备了具有半导体传导特性的n型Ba8Ga16-xZnxGe30I-型笼合物,研究了Zn部分置换Ga对化合物电传输特性的影响。研究表明所制备的化合物为单相的具有空间群Pm3-n的I-型笼合物。Zn掺杂前对应化合物表现为金属传导特性,Zn掺杂后对应化合物表现为典型的杂质半导体传导特性。室温下,随Zn掺杂量的增加,化合物的载流子浓度和载流子有效质量逐渐降低;Zn掺杂对室温载流子迁移率无明显影响。在300～900K温度范围内,随Zn掺杂量的增加对应化合物的电导率逐渐降低,Seebeck系数逐渐增加。Zn掺杂后对应化合物的功率因子与掺杂前相比有所降低,且达到最大值的温度都向低温方向偏移。n-type Ba8Ga16-xZnxGe30 type-I clathrates with conduction characteristic of semiconductor were prepared by combining melting method with spark plasma sintering （SPS） method.Effects of Zn partial substitute for Ga on the electrical transport properties were investigated.The results reveal that the obtained samples possess of single phase of type-I clathrates with space group pm3-n.The compound without Zn doping behaves metal conduction characteristic,but for Zn-doped samples show conduction characteristic of typical impurity semiconductor.The carrier concentration and the effective carrier mass decrease with the increasing of Zn content at room temperature;and Zn doping has no obvious effect on the carrier mobility at room temperature.The electrical conductivity decreases while Seebeck coefficient increases with the increasing of Zn content in the temperature range from 300 K to 900 K.The power factor of the Zn-doped samples is decreased to a certain degree compared with that of Ba8Ga16Ge30,and the temperature which the power factor reaches its maximum value shift toward the lower temperature after Zn doping.

关 键 词：I-型笼合物 热电材料 电传输特性 

分 类 号：O472[理学—半导体物理]