| Abstract Scope |
Bismuth telluride has long been the benchmark n-type thermoelectric material for near-room-temperature applications. However, its reliance on the scarce and toxic element tellurium motivates the development of more sustainable alternatives. In this study, we investigate tellurium-free systems including antimony-doped bismuth (Bi(Sb)) solid solutions and bismuth selenide (Bi2Se3) single crystals, synthesized via the Bridgman method. Bridgman-grown Bi(Sb) crystals achieved a room-temperature figure of merit of 0.4 at 300 K, representing a 30% improvement over previously reported values for polycrystalline SPS samples or Czochralski single crystals. Meanwhile, Bi2Se3 single crystals exhibited a 60% enhancement in power factor compared to polycrystalline counterparts, primarily due to improved electrical conductivity. These findings highlight the potential of Bridgman-grown Bi(Sb) and Bi2Se3 as non-toxic, and tellurium-free alternatives. Further studies on carrier mobility, defect chemistry, phase homogeneity, and band structure are ongoing to elucidate the mechanisms behind these performance enhancements and to guide future optimization of these systems. |