Ni掺杂CoSb_3化合物的热电性能及机理研究  

Study on thermoelectric properties and mechanism of Ni-doped CoSb_3 compounds

作　　者：朱云广[1] 沈鸿烈[1] 左连勇[1] 鲁林峰[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,江苏南京210016

出　　处：《电子元件与材料》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)

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.

关 键 词：Co3.5Ni0.5Sb12 热电性能 能带结构 态密度 

分 类 号：TN304.2[电子电信—物理电子学] O482.6[理学—固体物理]