Enhancing the Thermoelectric Performance of Cu2S/CuO Nanocomposites Through Energy-Filtering effect and Phonon Scattering

• Published in: Journal of inorganic and organometallic polymers and materials 2024-04, Vol.34 (4), p.1548-1563
• Main Authors: Mani, J., Radha, S., Prita, F. Jeni, Rajkumar, R., Arivanandhan, M., Anbalagan, G.
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Clean energy; Copper oxides; Copper sulfides; Electron microscopes; Energy conversion; Figure of merit; Inorganic Chemistry; Nanocomposites; Organic Chemistry; Polymer Sciences; Power factor; Seebeck effect; Thermal conductivity; Thermoelectric materials
• ISSN: 1574-1443; 1574-1451
• DOI: 10.1007/s10904-023-02885-5

Recently, thermoelectric (TE) materials have seized great attention for their role in clean energy conversion applications. Cu 2 S are p-type super-ionic conductors featuring a narrow band gap of 1.7 eV while exhibiting outstanding thermoelectric characteristics. The Cu 2 S matrix and the CuO nanoinclusions were successfully synthesized via solvothermal and hydrothermal routes, respectively. The morphological observations made through scanning and transmission electron microscope ensured the homogeneous distribution of CuO nanoinclusions in the Cu 2 S matrix, hence, the formation of standard Cu 2 S/CuO composites. In this work, we have introduced a “combined strategy” to boost the figure of merit (zT). The Seebeck coefficient reached the maximum of 271.86 μVK −1 at 573 K for the 20 wt% CuO sample (a 71.45% gain when compared to the pure Cu 2 S) owing to the filtration of low-energy carriers at the CuO potential barriers (2.5 eV). The Cu 2 S/20 wt% CuO sample achieved the minimum thermal conductivity values. At 573 K, We recorded a vast power factor value of 952.66 μWm −1  K −2 (32.23% gain) for the Cu 2 S/15 wt% CuO sample. These values are vastly higher than previously reported for the copper sulfides-based TE materials. Consequently, an optimised zT value of 0.44 (214.29% gain) was accomplished for the Cu 2 S/15 wt% CuO sample at 573 K. The strategy presented in our study can also be extended to other TE materials, especially for the promising copper chalcogenides to improve their zT values.