M Sinduja, Amirthapandian S, Magudapathy P, Srivastava S K, Asokan K
Materials Physics Division, Indira Gandhi Centre for Atomic Research, HBNI Kalpakkam, Kalpakkam 603102, India.
Materials Science Division, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India.
ACS Omega. 2018 Dec 27;3(12):18411-18419. doi: 10.1021/acsomega.8b02379. eCollection 2018 Dec 31.
The present study reports an enhancement of the power factor of BiTe nanorods NRs) by helium (He) ion irradiation. High-resolution transmission electron microscopy studies revealed the formation of amorphous layers on the surface of the NRs at the high ion fluence. This amorphous nature is due to the accumulation of migrating point defect clusters at the surface of the NRs. Raman scattering experiments provide further insight to the observed structural modifications. At higher ion fluence, impurity-dominated scattering processes significantly enhance the value of the Seebeck coefficient of BiTe NRs. The He ion irradiation up to the ion fluence of 1 × 10 ions/cm improves the thermoelectric transport properties with the highest power factor, 8.2 μW/m K, at 390 K. Further investigations may result in the possibility of fabricating the BiTe NRs as thermoelectric generators with a high power factor for space applications.
本研究报告了通过氦（He）离子辐照提高BiTe纳米棒（NRs）的功率因数。高分辨率透射电子显微镜研究表明，在高离子通量下，NRs表面形成了非晶层。这种非晶性质是由于迁移的点缺陷簇在NRs表面积累所致。拉曼散射实验为观察到的结构变化提供了进一步的见解。在较高的离子通量下，杂质主导的散射过程显著提高了BiTe NRs的塞贝克系数值。在离子通量达到1×10 ions/cm之前的He离子辐照，在390 K时以最高功率因数8.2 μW/m K改善了热电传输性能。进一步的研究可能会使制造具有高功率因数的BiTe NRs作为空间应用的热电发电机成为可能。
