【摘 要】
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The electronic structure and the thermoelectric properties of M2Zn5As4 (M=K,Rb) are studied by the first principles and the semiclassical BoltzTraP theory.It is determined that they are semiconductors
【机 构】
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College of Physics and Electrical Engineering, Anyang Normal University, Anyang Henan,455000China
【出 处】
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2014年全国博士后新材料技术与应用学术论坛
论文部分内容阅读
The electronic structure and the thermoelectric properties of M2Zn5As4 (M=K,Rb) are studied by the first principles and the semiclassical BoltzTraP theory.It is determined that they are semiconductors with an indirect band gap about 1 eV, which is much larger than that of Ca5Al2Sb6 (0.50 eV).The calculated electronic localization function indicates that they are typical Zintl bonding compounds.The combination of heavy and light bands near the valence band maximum may improve their thermoelectric performance.Rb2Zn5As4 exhibits relatively large Seebeck coefficients,high electrical conductivities, and the large "maximum" thermoelectric figures of merit(ZeT).Compared with Ca5Al2Sb6, the highest ZeT of Rb2Zn5As4 appears at relative low carrier concentration.For Rb2Zn4As5, the p-type doping may achieve a higher thermoelectric performance than n-type doping.The thermoelectric properties of Rb2Zn5As4 are possibly superior to those of Ca5Al2Sb6.
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