摘要
采用机械合金化结合冷等静压的方法制备了CoSb3和Co3.5Ni0.5Sb12化合物,并测量了其热电性能。利用基于密度泛函理论赝势平面波的方法对Ni掺杂前后的CoSb3的能带结构和态密度进行了计算,实验和理论计算结果表明:CoSb3的费密面位于导带和价带之间,其电阻率随温度的升高而降低,为非简并半导体;Co3.5Ni0.5Sb12的费密面进入导带,其电阻率随温度的升高而增大,为n型简并半导体;本实验条件下,Co3.5Ni0.5Sb12化合物的功率因子在550 K时出现最大值2 292.92μW/(m.K2),是未掺杂CoSb3化合物最大值的12倍。
CoSb3 and Co3.5Ni0.5Sb12 compounds were prepared by mechanical alloying combined with cold isostatic pressing methods.Their thermoelectric properties were also tested.The electronic structure of Ni-doped and undoped compounds were calculated using the first principle plane-wave pseudo-potential based on the density function theory.The experimental and calculated results show that the Fermi surface of CoSb3 locates between conduction band and valence band,CoSb3 is a semiconductor and its resistivity decreases with increasing temperature.The Fermi surface of Co3.5Ni0.5Sb12 moves to the conduction band and its resistivity increases with increasing temperature,exhibiting n-type degenerated semiconductor character.Under the condition of the experiment,the maximum value 2 292.92 μW /（m·K^2） of power factor for Co3.5Ni0.5Sb12 is obtained at 550 K,which is about 12 times as much as that of CoSb3.
出处
《电子元件与材料》
CAS
CSCD
北大核心
2010年第11期38-42,共5页
Electronic Components And Materials
基金
江苏省科技支撑计划资助项目(No.BE2008020)
