Bismuth Doping in Nanostructured Tetrahedrite: Scalable Synthesis and Thermoelectric Performance

Enhanced Thermoelectric Performance of Cu2Se via Nanostructure and Compositional Gradient

Forming co-alloying solid solutions has long been considered as an effective strategy for improving thermoelectric performance. Herein, the dense Cu_2−x(MnFeNi)_xSe (x = 0–0.09) with intrinsically low thermal conductivity was prepared by a melting-ball milling-hot pressing process. The influences of nanostructure and compositional gradient on the microstructure and thermoelectric properties of Cu₂Se were evaluated. It was found that the thermal conductivity decreased from 1.54 Wm⁻¹K⁻¹ to 0.64 Wm⁻¹K⁻¹ at 300 K via the phonon scattering mechanisms caused by atomic disorder and nano defects. The maximum zT value for the Cu_1.91(MnFeNi)_0.09Se sample was 1.08 at 750 K, which was about 27% higher than that of a pristine sample.

Gram-Scale Production of Photothermally Active Tetrahedrite Nanoparticles for Solar-Driven Water Evaporation

Pristine and substituted tetrahedrite nanoparticles have shown immense potential as low-cost and sustainable materials for energy conversion applications. However, the commonly used synthetic methods for their production are cumbersome and are not easily scalable. In this work, we report a facile colloidal synthetic protocol for the preparation of phase-pure samples of pristine (Cu₁₂ Sb₄ S₁₃ ) and Zn-substituted (Cu₁₁ ZnSb₄ S₁₃ ) tetrahedrite nanoparticles on the gram scale. Both tetrahedrite compositions were found to be photothermally responsive, enabling their use in solar-driven water evaporation.