Enhanced Lattice Symmetry via Mn Doping Boosts Electrical Transport Performance in Rhombohedral GeSe Thermoelectric Materials.

ABSTRACT: Low-symmetry thermoelectric material GeSe exhibits inherently low thermal conductivity but suppressed electrical transport properties. Here, we demonstrate that Mn doping in AgBiTe₂-alloyed rhombohedral GeSe introduces band engineering and further significantly enhances lattice symmetry. Mn-induced resonant energy levels enhance the density of states effective mass and significantly optimize the Seebeck coefficient. Crucially, elevated lattice symmetry reduces deformation potential and weakens phonon-electron coupling, triggering a 185% surge in carrier mobility despite a ~1.2-fold increase in the effective mass. The synergistically optimized Seebeck coefficient and electrical conductivity enable the high-symmetry (GeMn_0.005Se)_0.9(AgBiTe₂)_0.

SUBMITTER: Wang S 

PROVIDER: S-EPMC12645029 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature