Theoretical study on electronic structure and thermoelectric properties of PbS_xTe_1-x（x = 0.25, 0.5, and 0.75） solid solution

【摘要】 The electronic structure and thermoelectric（TE） properties of PbS_xTe_1-x（x = 0.25, 0.5, and 0.75） solid solution have been studied by combining the first-principles calculations and semi-classical Boltzmann theory. The special quasirandom structure（SQS） method is used to model the solid solutions of PbS_xTe_1-x, which can produce reasonable electronic structures with respect to experimental results. The maximum zT value can reach 1.67 for p-type PbS0.75Te0.25 and 1.30 for PbS0.5Te0.5 at 800 K, respectively. The performance of p-type PbS_xTe_1-x is superior to the n-type ones, mainly attributed to the higher effective mass of the carriers. The z T values for PbS_xTe_1-x solid solutions are higher than that of pure Pb Te and Pb S, in which the combination of low thermal conductivity and high power factor play important roles.更多还原

【Abstract】 The electronic structure and thermoelectric（TE） properties of PbS_xTe_1-x（x = 0.25, 0.5, and 0.75） solid solution have been studied by combining the first-principles calculations and semi-classical Boltzmann theory. The special quasirandom structure（SQS） method is used to model the solid solutions of PbS_xTe_1-x, which can produce reasonable electronic structures with respect to experimental results. The maximum zT value can reach 1.67 for p-type PbS0.75Te0.25 and 1.30 for PbS0.5Te0.5 at 800 K, respectively. The performance of p-type PbS_xTe_1-x is superior to the n-type ones, mainly attributed to the higher effective mass of the carriers. The z T values for PbS_xTe_1-x solid solutions are higher than that of pure Pb Te and Pb S, in which the combination of low thermal conductivity and high power factor play important roles.更多还原