Augmentation in the thermoelectric performance by integrating the natural minerals with synthetic tetrahedrite compounds

Thermoelectric (TE) materials -based devices are useful in converting heat into electricity. The cost of thermoelectric materials is mainly incurred from the purified pure metals used to make the efficient TE device. In the current study, tetrahedrite materials are considered due to their low cost, as these materials are abundant in mining waste of copper ores and also the most extensive sulfosalt on earth. Hence, to add value addition to mine waste materials, the composite approach has been employed to integrate the natural tetrahedrite (mine waste/ tailings product) materials with synthetically developed tetrahedrite materials in the lab for the current investigation. Further, the optimum quantity of mine waste addition is optimized by the systematic investigation of TE performance with varying the mine waste percentage addition to the synthetic tetrahedrite. The p -type synthetic Cu 10 FeZnSb 4 S 13 (Sample -A) tetrahedrite compound and 70 (Cu 10 FeZnSb 4 S 13 ) + 30 (natural/mine waste) (Sample -B) have been synthesized employing hot-press at 773 K along with the pristine (Cu 10 Fe 2 Sb 4 S 13 ) tetrahedrite compound. Moreover, the Seebeck coefficient is increased by 36 % (220 mu V/K to 300 mu V/K) for Sample -B, as compared to sample A and it is similar to 2 times higher as compared to the pristine compound. The power factor is increased by similar to 3 times that of the Sample -A (0.05 mW/mK 2 to 0.15 mW/mK 2 ). In addition, the thermal conductivity of Sample -B compound was further reduced by 30 % than Sample -A (0.98 W/mK to 0.69W/mK) and similar to 44 % more than the pristine compound. Finally, the zT of Sample -B increased to almost 3 times than Sample -A (0.05 - 0.15).