【摘要】 本文利用第一性原理计算并结合玻尔兹曼输运方程，预测了一种热电性能优良的新型Bi₂Te₃基材料，即单层BiSbTeSe₂。通过系统计算单层BiSbTeSe₂的电子能带结构和热电输运性质，发现单层BiSbTeSe₂在300 K时的塞贝克系数达到最高值(522μV·K^-1),在500 K时功率因子与弛豫时间的比值最大为5.78 W·m^-1·K^-2·s^-1。除此之外，单层BiSbTeSe₂还具有较低的晶格热导率和较高的迁移率。在最佳p型掺杂下，单层BiSbTeSe₂在500 K时的热电优值ZT高达3.95。单层BiSbTeSe₂的优良性能表明其在300～500 K的中温热电器件领域具有潜在的应用价值，可以为进一步开发高性能Bi₂Te₃基热电材料提供设计依据。更多还原

【Abstract】 Based on the first-principles calculation and Boltzmann transport equation, a new Bi₂Te₃-based material with excellent thermoelectric properties, namely monolayer BiSbTeSe₂, is predicted. By systematically calculating the electronic band structure and thermoelectric transport properties of monolayer BiSbTeSe₂, it is found that the maximum Seebeck coefficient of monolayer BiSbTeSe₂ reaches the highest value(522 μV·K^-1) at 300 K, and the maximum ratio of power factor to relaxation time at 500 K is 5.78 W·m^-1·K^-2·s^-1. In addition, the monolayer BiSbTeSe₂ has lower lattice thermal conductivity and higher mobility. Under the optimum p-type doping, the thermoelectric figure of merit ZT of monolayer BiSbTeSe₂ at 500 K is as high as 3.95. The excellent performance of monolayer BiSbTeSe₂ shows that it has potential application value in the field of medium-temperature electrical devices in the temperature range of 300～500 K, which can provide design basis for further developing high-performance Bi₂Te₃-based thermoelectric materials.更多还原