摘要
用水热法在473K下反应24h,制备了Bi-Te-Se三元合金。其粉末产物由结构相同成份接近的两相Bi-Te-Se合金组成。粉末在523K,50MPa压力下热压成的块材也是两相结构。粉末和块体材料的微观形貌均由层片状颗粒组成,层片厚度为100nm左右。通过改变Te的相对含量,可以调节施主掺杂浓度。材料具有很低的热导率,在349K时试样Bi2Te2.85Se0.45具有晶格热导率最低值为0.33W/m.K。此时,它也具有最高的ZT值为0.60。
Bi-Te-Se alloys were synthesized by hydrothermal method at 473K for 24h. The synthesized powders were composed of two kinds of Bi-Te-Se ternary alloys with the same structure. The powders were hot pressed into pellets at 523K under 50MPa, which were composed of two phases too. Both the powders and pellets exhibited layered particles with the thickness of about 100nm. The doping concentration can be optimized by changing the content of Te. The materials have remarkably low thermal conductivity. The lowest lattice thermal conductivity was found to be 0.33W/m·K at 349K and the maximum ZT value 0.60 in Bi2Te2.85Se0.45. Improved thermoelectric properties could be expected by synthesizing anisotropic materials and doping with iodine based on this work.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2006年第10期1561-1563,共3页
Journal of Functional Materials
基金
国家自然科学基金资助项目(50471039
50522203)
