High-crystallinity OD, ID and 2D Bi_2Te_3 nanocrystals have been synthesized using the pyrolysis of organometallic compound method. The growth process of Bi_2Te_3 nanocrystals was revealed by transmission electron microscopy (TEM) images. Samples synthesized at the temperature of 35°C show a dominant morphology of OD nanoparticle or 1D nanorod, while samples synthesized at the temperature above 75 °C show a dominant morphology of 2D nanoplate. Phonon vibrational behavior was investigated by Raman spectroscopy. 2D nanoplates show similar Raman features to few-quintuple thick Bi_2Te_3 layers, while OD and ID nanostructures show a blueshifted A_(lg)~2mode and a much stronger A_(lu) mode. This is the report about Raman spectra obtained on small Bi_2Te_3 nanoparticle and nanorod whose size is within the strong quantum confinement region.
展开▼
