Wei Meng, Ma Hong-Li, Nie Min-Yue, Li Ying-Zhen, Zheng Zhuang-Hao, Zhang Xiang-Hua, Fan Ping
Shenzhen Key Laboratory of Advanced Thin Films and Applications, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes), UMR6226, F-35000 Rennes, France.
Materials (Basel). 2023 Feb 2;16(3):1271. doi: 10.3390/ma16031271.
The Skutterudites CoSb material has been the focus of research for the conversion applications of waste heat to electricity due to its ability to accommodate a large variety of ions in the cages that have been proven effective in improving the thermoelectric performance. Although the co-doped CoSb bulk materials have attracted increasing attention and have been widely studied, co-doped CoSb thin films have been rarely reported. In this work, Ag and Ti were co-doped into CoSb thin films via a facile in situ growth method, and the influence of doping content in the thermoelectric properties was investigated. The results show that all the Ag and Ti co-doped CoSb thin films contain a pure well-crystallized CoSb phase. Compared to the un-doped thin film, the co-doped samples show simultaneous increase in the Seebeck coefficient and the electrical conductivity, leading to a distinctly enhanced power factor. The high power factor value can reach ~0.31 mWmK at 623 K after appropriate co-doping, which is two times the value of the un-doped thin film we have been obtained. All the results show that the co-doping is efficient in optimizing the performance of the CoSb thin films; the key point is to control the doping element content so as to obtain high thermoelectric properties.
方钴矿CoSb材料因其能够在笼状结构中容纳多种离子，且已被证明对提高热电性能有效，故而成为废热转化为电能应用研究的焦点。尽管共掺杂的CoSb块体材料已引起越来越多的关注并得到广泛研究，但共掺杂的CoSb薄膜却鲜有报道。在本工作中，通过一种简便的原位生长方法将Ag和Ti共掺杂到CoSb薄膜中，并研究了掺杂含量对热电性能的影响。结果表明，所有Ag和Ti共掺杂的CoSb薄膜均含有纯的结晶良好的CoSb相。与未掺杂薄膜相比，共掺杂样品的塞贝克系数和电导率同时增加，导致功率因数显著提高。经过适当的共掺杂后，在623 K时高功率因数值可达到约0.31 mWmK，这是我们所获得的未掺杂薄膜值的两倍。所有结果表明，共掺杂对于优化CoSb薄膜的性能是有效的；关键在于控制掺杂元素的含量以获得高热电性能。
