Y_(2)NT_(2)(T=O,F,OH)的热电性质

Thermoelectric Properties of Y_(2)NT_(2)(T=O,F,OH)

利用第一性原理,结合玻尔兹曼输运理论,研究Y_(2)NT_(2)(T=O,F,OH)的热电性质,对电子的弛豫时间和晶格热导率分别用形变势理论和Slack模型计算.结果表明,Y_(2)NO_(2)和Y_(2)N(OH)_(2)的塞贝克系数在室温下均大于690μV/K;对比电子和声子热导率发现,电子对热导率的贡献占主要部分,Y_(2)NO_(2)和Y_(2)N(OH)_(2)在900 K时有最大ZT值,尤其是p型Y_(2)NO_(2),当载流子浓度为9.05×10^(11) cm^(-2)时达到最大值0.90,这表明它是一种潜在的中温热电材料.

The thermoelectric properties of Y_(2)NT_(2)(T=O,F,OH)were studied by first-principles calculations combined with Boltzmann transport theory.For the relaxation time of electrons and lattice thermal conductivity,deformation potential theory and Slack model were used respectively.The results show that the Seebeck coefficients of Y_(2)NO_(2) and Y_(2)N(OH)_(2) are both greater than 690μV/K at room temperature.Comparing the thermal conductivity of electrons and phonons,it is found that the contribution of electrons to the thermal conductivity occupies the main part,Y_(2)NO_(2) and Y_(2)N(OH)_(2) has a maximum ZT value at 900 K,especially for p-type Y_(2)NO_(2),which reaches a maximum value of 0.90 when the carrier concentration is 9.05×10^(11) cm^(-2).This suggests that it is a potential medium-temperature thermoelectric material.