About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Alloys and Compounds for Thermoelectric and Solar Cell Applications XIV
|
| Presentation Title |
Multication Vacancy Engineering Creating Van der Waals Gap Pathways Unlocks High‑Performance SnSe Thermoelectrics |
| Author(s) |
Bo-Chia Chen, Ching-Yu Chiang, Wan-Zhen Hsieh, Ying-Chun Chao, Cheng-Rong Hsing, Hung-Wei Yen, Ching-Ming Wei, Hsin-Jay Wu |
| On-Site Speaker (Planned) |
Bo-Chia Chen |
| Abstract Scope |
Layered SnSe offers high in‑plane conductivity through its VDW gaps, but abundant Sn vacancies keep hole density below the optimum value. Earlier studies mitigated this deficiency with sodium doping, which boosted carriers, yet posed safety issues. DFT screening pinpoints Mg as a vacancy healer with strongly negative formation energy; Mg fills Sn sites, after which Ag and Cu occupy remaining vacancies or lie within VDW gaps. This dual occupancy expands interlayer conduction channels and intensifies phonon scattering, sustaining low lattice thermal conductivity. XRF and XAS mappings confirm Ag and Cu distributions between the gaps, while molecular‑dynamics simulations show lateral Ag and Cu motion inside VDW gaps along the b‑axis, rationalizing the mobility gains. The multication‑engineered single crystal delivers an average zT ~ 0.8 from 300–600 K and ~5 % conversion efficiency under a temperature gradient of 200 K, establishing a sodium‑free path to robust mid‑temperature thermoelectrics. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Energy Conversion and Storage, Machine Learning, |