{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T15:01:02Z","timestamp":1786114862936,"version":"build-2736575974"},"reference-count":39,"publisher":"American Chemical Society (ACS)","issue":"30","license":[{"start":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T00:00:00Z","timestamp":1784246400000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T00:00:00Z","timestamp":1784246400000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T00:00:00Z","timestamp":1784246400000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"name":"Department of Science and Technology, Ministry of Science and Technology","award":["AI\/1\/65\/ARCI\/2014"],"award-info":[{"award-number":["AI\/1\/65\/ARCI\/2014"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Nanostructured PbTe-based compounds, including n-type LAST-m (AgPbmSbTem+2) and p-type LASTT-m (Ag(Pb1\u2212xSnx)mSbTem+2), exhibit high thermoelectric performance, but their long-term thermal stability remains a major limitation for high-temperature applications. In this work, we provide detailed insights into the origin of thermal instabilities in p-type LASTT compounds by studying the Ag0.9(Pb0.5Sn0.5)10Sb0.8Te12 (LASTT-10) composition synthesized via melting, annealing, and spark plasma sintering. The prepared bulk samples exhibit a high zT of \u223c1.05 \u00b1 0.10 at 673 K. Systematic thermal cycling and isothermal annealing experiments reveal that the observed irreversible changes in transport properties stem from microstructural evolution of Te-rich (Ag1\u2212xSbx)1+yTe2 (x = 0.12, y = 0.18) secondary phases located at the grain boundaries. Differential thermal analysis of LASTT-10 identifies an endothermic reaction \u223c630 K associated with the thermodynamic instability of the grain boundary phases. Beyond 610 K, (Ag1\u2212xSbx)1+yTe2 undergoes multiple phase transformations, which lead to macroscopic thermal instability. Cyclic power generation tests indicate a stable performance for LASTT-10 below 610 K, with maximum power density \u223c0.51 W\/cm2 and conversion efficiency \u223c4.3% at \u0394T \u223c316 K. These findings clarify the mechanisms underlying the thermal degradation in LASTT-10 and highlight critical parameters for improving the thermal robustness of PbTe-based thermoelectric materials for high-temperature power generation.<\/jats:p>","DOI":"10.1021\/acsami.6c08078","type":"journal-article","created":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T17:09:11Z","timestamp":1784308151000},"page":"41226-41235","source":"Crossref","is-referenced-by-count":0,"title":["Role of Grain Boundary Features in the Thermal Stability of LASTT-10 Thermoelectric Materials"],"prefix":"10.1021","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1182-6655","authenticated-orcid":true,"given":"Jayachandran","family":"Babu","sequence":"first","affiliation":[{"name":"International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), IIT Madras Research Park , , ,","place":["Chennai, India, 600 113"]},{"name":"Indian Institute of Technology (IIT), Bombay , , ,","place":["Mumbai, India, 400 076"]},{"name":"National Institute for Materials Science (NIMS) , , Namiki , ,","place":["Tsukuba, Japan, 305 0044"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5442-6328","authenticated-orcid":true,"given":"Ravi","family":"Gautam","sequence":"additional","affiliation":[{"name":"National Institute for Materials Science (NIMS) , , Sengen , ,","place":["Tsukuba, Japan, 305 0047"]},{"name":"Malaviya National Institute of Technology (MNIT) , , ,","place":["Jaipur, India, 302017"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7856-7897","authenticated-orcid":true,"given":"Hossein","family":"Sepehri-Amin","sequence":"additional","affiliation":[{"name":"National Institute for Materials Science (NIMS) , , Sengen , ,","place":["Tsukuba, Japan, 305 0047"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2682-1846","authenticated-orcid":true,"given":"Takao","family":"Mori","sequence":"additional","affiliation":[{"name":"National Institute for Materials Science (NIMS) , , Namiki , ,","place":["Tsukuba, Japan, 305 0044"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8261-9784","authenticated-orcid":true,"given":"Titas","family":"Dasgupta","sequence":"additional","affiliation":[{"name":"Indian Institute of Technology (IIT), Bombay , , ,","place":["Mumbai, India, 400 076"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3771-2939","authenticated-orcid":true,"given":"Duraisamy","family":"Sivaprahasam","sequence":"additional","affiliation":[{"name":"International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), IIT Madras Research Park , , ,","place":["Chennai, India, 600 113"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,7,17]]},"reference":[{"key":"2026080518114660600_cit1","doi-asserted-by":"publisher","first-page":"1314","DOI":"10.1016\/j.apenergy.2018.10.102","article-title":"Quantification of Global Waste Heat and Its Environmental Effects","volume":"235","author":"Firth","year":"2019","journal-title":"Appl. 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