<p>Silver selenide (Ag<sub>2</sub>Se) is a promising n-type thermoelectric material because of its excellent thermoelectric performance near room temperature, but conventional methods for fabricating bulk Ag<sub>2</sub>Se require high temperatures and pressures making scalable production a challenge. Here, a facile and scalable strategy is presented for fabricating high-performance dense Ag<sub>2</sub>Se<sub>1.2</sub> thermoelectric material by incorporating excess Se in solution-processed Ag<sub>2</sub>Se powders. The excess Se facilitates liquid-phase-assisted grain growth during annealing at 623&#xa0;K under ambient pressure, which greatly improves microstructural properties such as the grain connectivity and bulk density. In experiments, Ag<sub>2</sub>Se<sub>1.2</sub> exhibited a high-power factor and reduced lattice thermal conductivity leading to a maximum figure of merit of 0.927 at 393&#xa0;K. The shape-conformable nature of Ag<sub>2</sub>Se<sub>1.2</sub> also allows for the fabrication of cylindrical thermoelectric generators with a stable output voltage and power at various temperature differences. This strategy is a highly effective approach for improving not only the thermoelectric and mechanical performances of Ag<sub>2</sub>Se but also its applicability in curved or flexible energy harvesting devices.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Facile and scalable strategy for fabricating dense bulk Ag2Se as a high-performance thermoelectric material

  • Myeong Hoon Jeong,
  • Byoungwook Park,
  • Jungwon Kim,
  • Mijeong Han,
  • Young Hun Kang

摘要

Silver selenide (Ag2Se) is a promising n-type thermoelectric material because of its excellent thermoelectric performance near room temperature, but conventional methods for fabricating bulk Ag2Se require high temperatures and pressures making scalable production a challenge. Here, a facile and scalable strategy is presented for fabricating high-performance dense Ag2Se1.2 thermoelectric material by incorporating excess Se in solution-processed Ag2Se powders. The excess Se facilitates liquid-phase-assisted grain growth during annealing at 623 K under ambient pressure, which greatly improves microstructural properties such as the grain connectivity and bulk density. In experiments, Ag2Se1.2 exhibited a high-power factor and reduced lattice thermal conductivity leading to a maximum figure of merit of 0.927 at 393 K. The shape-conformable nature of Ag2Se1.2 also allows for the fabrication of cylindrical thermoelectric generators with a stable output voltage and power at various temperature differences. This strategy is a highly effective approach for improving not only the thermoelectric and mechanical performances of Ag2Se but also its applicability in curved or flexible energy harvesting devices.