{"title":"Enhanced thermoelectric performance in AgSbTe2 with extremely low thermal conductivity via grain boundary defects","authors":"Kaiqi Zhang, Jing Wang, Shuang Liu, Xiao Ji, Chenhao Gao, Bin Zhang, Guiwen Wang, Guoyu Wang, Yuqing Wang, Yun Zhou, Honghui Wang, Xu Lu, Xiaoyuan Zhou","doi":"10.1063/5.0255308","DOIUrl":null,"url":null,"abstract":"A delicate balance between high electrical conductivity and ultra-low glass-like thermal conductivity is critical for enhancing thermoelectric performance. Here, by introducing grain boundary trapping states into the AgSbTe2 matrix, the thermally activated release of carriers at elevated temperatures enhances electrical conductivity, while the increased barrier potential induces an energy filtering effect that sustains a high Seebeck coefficient. This synergistic optimization of electrical conductivity and Seebeck coefficient significantly enhances the power factor. Additionally, numerous point defects and a higher density of grain boundaries further enhance phonon scattering, resulting in a 33% reduction in glass-like thermal conductivity compared to the pristine sample. With enhanced power factor and reduced lattice thermal conductivity, Fe-doped AgSbTe2 achieves a remarkable peak zT of 1.8 at 623 K and an impressive zTavg of 1.4 over the temperature range of 323–623 K, showcasing its leading performance in the field. By selecting proper contact layer materials with matched thermal expansion coefficients, low interfacial resistivity was achieved, enabling a single-leg thermoelectric device with ∼10% efficiency under a 323 K temperature difference.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"51 1","pages":""},"PeriodicalIF":3.6000,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Physics Letters","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1063/5.0255308","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
A delicate balance between high electrical conductivity and ultra-low glass-like thermal conductivity is critical for enhancing thermoelectric performance. Here, by introducing grain boundary trapping states into the AgSbTe2 matrix, the thermally activated release of carriers at elevated temperatures enhances electrical conductivity, while the increased barrier potential induces an energy filtering effect that sustains a high Seebeck coefficient. This synergistic optimization of electrical conductivity and Seebeck coefficient significantly enhances the power factor. Additionally, numerous point defects and a higher density of grain boundaries further enhance phonon scattering, resulting in a 33% reduction in glass-like thermal conductivity compared to the pristine sample. With enhanced power factor and reduced lattice thermal conductivity, Fe-doped AgSbTe2 achieves a remarkable peak zT of 1.8 at 623 K and an impressive zTavg of 1.4 over the temperature range of 323–623 K, showcasing its leading performance in the field. By selecting proper contact layer materials with matched thermal expansion coefficients, low interfacial resistivity was achieved, enabling a single-leg thermoelectric device with ∼10% efficiency under a 323 K temperature difference.
期刊介绍:
Applied Physics Letters (APL) features concise, up-to-date reports on significant new findings in applied physics. Emphasizing rapid dissemination of key data and new physical insights, APL offers prompt publication of new experimental and theoretical papers reporting applications of physics phenomena to all branches of science, engineering, and modern technology.
In addition to regular articles, the journal also publishes invited Fast Track, Perspectives, and in-depth Editorials which report on cutting-edge areas in applied physics.
APL Perspectives are forward-looking invited letters which highlight recent developments or discoveries. Emphasis is placed on very recent developments, potentially disruptive technologies, open questions and possible solutions. They also include a mini-roadmap detailing where the community should direct efforts in order for the phenomena to be viable for application and the challenges associated with meeting that performance threshold. Perspectives are characterized by personal viewpoints and opinions of recognized experts in the field.
Fast Track articles are invited original research articles that report results that are particularly novel and important or provide a significant advancement in an emerging field. Because of the urgency and scientific importance of the work, the peer review process is accelerated. If, during the review process, it becomes apparent that the paper does not meet the Fast Track criterion, it is returned to a normal track.