Transmission electron microscopy observation of the half-Heusler compound Ti0.5(Zr0.5Hf0.5)0.5NiSn0.998Sb0.002

Received 25 May 2008; received in revised form 24 June 2008; accepted 24 June 2008.

The high-performance thermoelectric compound Ti0.5(Zr0.5Hf0.5)0.5NiSn0.998Sb0.002 with half-Heusler lattice was studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Each half-Heusler peak in the XRD pattern was accompanied by a bump at the high-angle side. Granular domains, a few nanometers in size, were observed in a bright-field TEM image. Fourier transformation and inverse Fourier transformation of the high-resolution TEM image revealed that the granular structure consists of half-Heusler domains with ordering and with disordering between second nearest neighbor atoms.

Keywords: High-resolution electron microscopy, Half-Heusler phase, Melt spinning, X-ray diffraction, Thermoelectric material

a Graduate School of Science and Technology, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan

b Department of Materials Science and Engineering, Faculty of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan

Corresponding author. Tel.: +81 95 819 2636; fax: +81 95 819 2634.

PII: S1359-6462(08)00488-0

doi:10.1016/j.scriptamat.2008.06.039

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