Scalable Polyol Synthesis of Doped Bi ₂ Te ₃ with Enhanced Thermoelectric Performance

Bi2Te3-based compounds remain one of the most effective thermoelectric materials for low-temperature applications, and their properties can be further enhanced by nanostructuring and dopant incorporation. This work demonstrates significant enhancement of n-type Bi2Te3 synthesized by scalable, solution-based methods through the incorporation of copper, sulfur, and selenium. A peak zT of 1.23 at 383 K and an average zT of 1.11 between 314 and 533 K were achieved. Multiple dopant incorporation strategies were evaluated to identify the most effective approach for achieving uniform dopant distribution, and anisotropy effects arising from preferred crystallite orientation were investigated, demonstrating its influence on transport properties. Overall, this study demonstrates a fast, cost-effective, and scalable synthesis route for Bi2Te3 with enhanced thermoelectric performance, advancing the development of efficient materials for waste heat recovery and sustainable energy technologies.