{"title":"Enhanced Thermoelectric and Mechanical Properties of ZrNiSn Half-Heusler Compounds by Excess Ag Doping at Ni Sites","authors":"Xinghui Wang, Yu Yan, Wen Zhang, Huijun Kang, Enyu Guo, Zongning Chen, Rongchun Chen, Tongmin Wang","doi":"10.1007/s40195-025-01853-x","DOIUrl":null,"url":null,"abstract":"<div><p>Different from full-Heusler compounds, four vacancies in the face-centered cubic crystal structure provide extra sites for enhancing the thermoelectric properties of half-Heusler compounds (HHs). Herein, excess Ag is introduced to the Ni-site vacancies of ZrNiSn to optimize thermoelectric properties. The ZrNiAg<sub><i>x</i></sub>Sn (<i>x</i> = 0, 0.01, 0.02, and 0.03) samples were synthesized by levitation melting and spark plasma sintering. Remarkably, the introduction of excess Ag significantly improves the Seebeck coefficient of ZrNiAg<sub>0.01</sub>Sn, and a peak power factor of ~ 4.52 mW/(m K<sup>2</sup>) is achieved in ZrNiAg<sub>0.01</sub>Sn at 923 K, which is enhanced by 22.8% than that of pristine ZrNiSn. As a result, the figure of merit <i>zT</i> of pristine ZrNiSn is enhanced from ~ 0.60 to ~ 0.72 of ZrNiAg<sub>0.01</sub>Sn at 923 K. Additionally, grain refinement effectively increases the Vickers hardness of ZrNiAg<sub>0.01</sub>Sn, which is enhanced by 32.8% than that of pristine ZrNiSn. These results demonstrate a viable doping strategy for designing ZrNiSn-based HHs with excellent thermoelectric and mechanical properties.</p></div>","PeriodicalId":457,"journal":{"name":"Acta Metallurgica Sinica-English Letters","volume":"38 5","pages":"763 - 771"},"PeriodicalIF":2.9000,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Acta Metallurgica Sinica-English Letters","FirstCategoryId":"1","ListUrlMain":"https://link.springer.com/article/10.1007/s40195-025-01853-x","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"METALLURGY & METALLURGICAL ENGINEERING","Score":null,"Total":0}
引用次数: 0
Abstract
Different from full-Heusler compounds, four vacancies in the face-centered cubic crystal structure provide extra sites for enhancing the thermoelectric properties of half-Heusler compounds (HHs). Herein, excess Ag is introduced to the Ni-site vacancies of ZrNiSn to optimize thermoelectric properties. The ZrNiAgxSn (x = 0, 0.01, 0.02, and 0.03) samples were synthesized by levitation melting and spark plasma sintering. Remarkably, the introduction of excess Ag significantly improves the Seebeck coefficient of ZrNiAg0.01Sn, and a peak power factor of ~ 4.52 mW/(m K2) is achieved in ZrNiAg0.01Sn at 923 K, which is enhanced by 22.8% than that of pristine ZrNiSn. As a result, the figure of merit zT of pristine ZrNiSn is enhanced from ~ 0.60 to ~ 0.72 of ZrNiAg0.01Sn at 923 K. Additionally, grain refinement effectively increases the Vickers hardness of ZrNiAg0.01Sn, which is enhanced by 32.8% than that of pristine ZrNiSn. These results demonstrate a viable doping strategy for designing ZrNiSn-based HHs with excellent thermoelectric and mechanical properties.
期刊介绍:
This international journal presents compact reports of significant, original and timely research reflecting progress in metallurgy, materials science and engineering, including materials physics, physical metallurgy, and process metallurgy.