Thermoelectric properties of nanostructured half-Heusler Hf0.25Zr0.75NiSn0.99Sb0.01 were characterized before and after 2.5 MeV proton irradiation. A unique high-sensitivity scanning thermal microprobe was used to simultaneously map the irradiation effect on thermal conductivity and Seebeck coefficient with spatial resolution less than 2 μm. The thermal conductivity profile along the depth from the irradiated surface shows excellent agreement with the irradiation-induced damage profile from simulation. The Seebeck coefficient was unaffected while both electrical and thermal conductivities decreased by 24%, resulting in no change in thermoelectric figure of merit ZT. Reductions in thermal and electrical conductivities are attributed to irradiation-induced defects that act as scattering sources for phonons and charge carriers.
Copyright (2018) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in:
Kempf, N., Karthik, C., Jaques, B.J., Gigax, J., Shao, l., Butt, D.P.,... Zhang, Y. (2018). Proton Irradiation Effect on Thermoelectric Properties of Nanostructured N-Type Half-Heusler Hf0.25Zr0.75NiSn0.99Sb0.01. Applied Physics Letters, 112(24), 243902.
and may be found at doi: 10.1063/1.5025071
Chinnathambi, Karthik and Jaques, Brian J.. (2018). "Proton Irradiation Effect on Thermoelectric Properties of Nanostructured N-Type Half-Heusler Hf0.25Zr0.75NiSn0.99Sb0.01". Applied Physics Letters, 112(24), 243902-1 - 243902-4.