Sadia Yatir, Lumbroso Dan, Gelbstein Yaniv
The Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva 8400711, Israel.
Nuclear Research Center of the Negev, NRCN, Beer-Sheva 8400711, Israel.
Materials (Basel). 2023 Feb 25;16(5):1902. doi: 10.3390/ma16051902.
Most high-performance thermoelectric materials require either expensive, rare, or toxic elements. By doping TiNiSn, a low-cost, abundant thermoelectric compound, with copper as an n-type donor, some optimization can be performed for such materials. Ti(NiCu)Sn was synthesized by arc melting followed by heat treatment and hot pressing. The resulting material was analyzed for its phases using XRD and SEM and its transport properties. Cu undoped and 0.05/0.1% doped samples showed no additional phases in addition to the matrix half-Heusler phase, while the 1% copper doping initiated some TiSn and TiSn precipitation. The transport properties showed that copper acts as an n-type donor while also lowing the lattice thermal conductivity of the materials. the sample containing 0.1% copper showed the best figure of merit, ZT, with a maximal value of 0.75 and an average value of 0.5 through 325-750 K showing a 125% improvement over the undoped sample of TiNiSn.
大多数高性能热电材料需要昂贵、稀有或有毒的元素。通过用铜作为n型施主掺杂低成本、储量丰富的热电化合物TiNiSn，可以对这类材料进行一些优化。通过电弧熔炼，然后进行热处理和热压合成了Ti(NiCu)Sn。使用X射线衍射（XRD）和扫描电子显微镜（SEM）对所得材料的相及其输运性质进行了分析。未掺杂铜以及掺杂0.05%/0.1%铜的样品除了基体半赫斯勒相外没有显示出其他相，而1%铜掺杂引发了一些TiSn和TiSn沉淀。输运性质表明，铜作为n型施主，同时也降低了材料的晶格热导率。含0.1%铜的样品显示出最佳的优值ZT，在325 - 750K范围内最大值为0.75，平均值为0.5，比未掺杂的TiNiSn样品提高了125%。
