Enhanced thermoelectric performance of PbTe within the orthorhombic P n m a phase

摘要: The thermoelectric properties of PbTe within the NaCl (B1) and orthorhombic $Pnma$ phases are extensively studied by ab initio calculations using full-potential linearized augmented plane-wave method semiclassical Boltzmann theory. $n$- $p$-type Seebeck coefficients for B1 structure suggested that energy band gap plays an important role in determining properties, but only at lower carrier concentrations. We found $n$-doped phase $6.5\phantom{\rule{0.3em}{0ex}}\mathrm{GPa}$ has a larger coefficient than zero pressure, comparable electric conductivity. This fact could be well understood large density states conduction anisotropy constant surface. Our also predicted largest $n$-type ZT values 300 $600\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ can reach up to 0.9 1.59, respectively, which two times those pressure. current theory strongly suggests is excellent material. It desirable synthesize ambient pressure making use its high performance.