Speakers

Developing efficient and eco-friendly thermoelectric materials requires precise control over structural symmetry and electronic transport. Tin monosulfide (SnS), a layered IV–VI semiconductor, has emerged as a promising candidate for these applications in the moderate temperature range, benefiting from inherently low thermal conductivity due to strong lattice anharmonicity from its distorted rock-salt structure. We’ve grown both poly and single crystalline SnS utilizing solid state reaction and Bridgeman method, respectively. Co-doping of Na and Ag into SnS yield enhanced electric conductivity and high thermoelectric properties. The combination of the symmetry engineering and the dopant characteristics generated the band convergence for favorable thermoelectric properties, resulting in a record high power factor of ~104 µW cm^-1 K^-2 at room temperature. With this advancement, our single-crystalline SnS exhibited a relatively high zT value of 1.1 and 2.04 at 300 and 523 K, respectively. This high zT was supported by a conversion efficiency of 3.3% under a 250 K temperature gradient. Overall, these findings establish a viable route for utilizing SnS as low-cost thermoelectric power generation near ambient conditions and expanding its potential for solid-state cooling applications.