Enhanced Charge Transport at the Interface in P3HT-Tellurium Nanowires Hybrid Materials for High Thermoelectric Performance

The combination of inorganic nanostructured materials within organic conducting polymers have attracted tremendous interest for designing new organic-inorganic hybrid thermoelectric (TE) materials for harvesting waste heat energy. Due to their mechanical flexibility and simple fabrication process, inorganic-organic hybrid TE materials are considered to be promising candidates for flexible energy harvesting devices. In this research, we explored the influence of the molecular weight of poly(3-hexylthiophene-2,5-diyl) (P3HT) combined with longer lengths (~10µm) of tellurium (Te) nanowires on the thermoelectric transport characteristics of organic-inorganic hybrid thermoelectric materials. Our findings indicate that the integration of longer tellurium nanowires with P3HT of different molecular weights (ranging from 50 to 143 kDa) enhances the thermoelectric properties of the hybrid material, resulting in a power factor of 303±38 µW/mK² for Te₈₀-P3HT₂₀ hybrid material with optimal doping. Thermal conductivity measurements were performed, and value of 0.25 W/m-K was achieved for Te₈₀-P3HT₂₀. ZT value of 0.36 was attained at room temperature, marking the highest reported value for such Te-P3HT based hybrid materials to date. This research offers critical insights into the synergistic effects of nanowire length and polymer molecular weight, setting the stage for the development and refinement of advanced thermoelectric materials tailored for efficient energy conversion applications.

Reference:
Oxidation Control to Augment Interfacial Charge Transport in Te-P3HT Hybrid Materials for High Thermoelectric Performance, Adv. Sci. , DOI:10.1002/advs.202400802
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