We have studied topological insulator Bi2Te3 nanoparticles mixed with insulating Al2O3 nanoparticles by means of 125Te nuclear magnetic resonance (NMR) and impedance spectroscopy. Our 125Te NMR lineshape measurements revealed the Knight shift of a satellite peak that increased with the mixing ratio of the Al2O3 nanoparticles, indicating that the mixing increases the surface-to-volume ratio of the Bi2Te3 nanoparticles. It is also shown that the impedance spectroscopy can be employed as a simple and effective means of distinguishing the surface electrical properties of the topological insulators in general.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (Project Nos. 2016R1D1A1A09917003 and 2016R1D1A1B03931144). The Korea Basic Science Institute (KBSI) is acknowledged for the measurements.
© 2018 IOP Publishing Ltd.
- Te nuclear magnetic resonance
- impedance spectroscopy
- surface electrical properties
- topological insulator BiTe nanoparticles
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Polymers and Plastics
- Metals and Alloys