Anish Kumar,
- , Department of Mechanical engineering, BIT, Sindri, , India
Abstract
Thermoelectric materials capable of efficient energy conversion near room temperature are critical for waste heat recovery applications. In this work, solution-grown Bi₂Te₃ nanorods were synthesized via a trioctylphosphine-assisted thermal decomposition route, and the influence of surfactant-induced nanostructuring on their thermoelectric properties was systematically investigated. Structural analysis using X-ray diffraction and Rietveld refinement confirmed the formation of rhombohedral Bi₂Te₃ with the emergence of Bi₂Te₃–BiTe nanocomposites at higher surfactant concentrations. Electron microscopy revealed one-dimensional nanorods with crystallite sizes tunable down to ~40 nm. Raman spectroscopy showed the appearance of IR-active A₁u modes, indicating a ligand-induced breakdown of inversion symmetry due to the formation of sub-quintuple layers along the nanorod axis. Thermoelectric measurements demonstrated n-type conduction with a significant enhancement in Seebeck coefficient attributed to carrier energy filtering at grain boundaries and quantum confinement effects. An optimized surfactant concentration yielded a maximum power factor of 348.7 μW m⁻¹ K⁻² at 300 K, exceeding values reported for comparable solution-processed Bi₂Te₃ systems. The combined effects of reduced crystallite size, controlled barrier height, and nanocomposite formation establish surfactant-engineered Bi₂Te₃ nanorods as promising candidates for high-performance near-room-temperature thermoelectric applications.
Keywords: Thermoelectric materials, Bi₂Te₃ nanorods, Solution growth, Energy filtering, Nanocomposites.
[This article belongs to International Journal of Energy and Thermal Applications ]
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International Journal of Energy and Thermal Applications
| Volume | 04 | |
| Issue | 01 | |
| Received | 23/02/2026 | |
| Accepted | 07/03/2026 | |
| Published | 25/03/2026 | |
| Publication Time | 30 Days |