Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
University of Science and Technology of China, Jinzhai Rd. 96, Hefei, 230026, China.
Nanoscale Res Lett. 2016 Dec;11(1):308. doi: 10.1186/s11671-016-1510-x. Epub 2016 Jun 24.
Physical vapour deposition (PVD) is used to grow millimetre-long Bi2Te3 sub-micron belts catalysed by TiO2 nanoparticles. The catalytic efficiency of TiO2 nanoparticles for the nanostructure growth is compared with the catalyst-free growth employing scanning electron microscopy. The catalyst-coated and catalyst-free substrates are arranged side-by-side, and overgrown at the same time, to assure identical growth conditions in the PVD furnace. It is found that the catalyst enhances the yield of the belts. Very long belts were achieved with a growth rate of 28 nm/min. A ∼1-mm-long belt with a rectangular cross section was obtained after 8 h of growth. The thickness and width were determined by atomic force microscopy, and their ratio is ∼1:10. The chemical composition was determined to be stoichiometric Bi2Te3 using energy-dispersive X-ray spectroscopy. Temperature-dependent conductivity measurements show a characteristic increase of the conductivity at low temperatures. The room temperature conductivity of 0.20 × 10(5) S m (-1) indicates an excellent sample quality.
采用物理气相沉积（PVD）在 TiO2 纳米颗粒催化下生长毫米级 Bi2Te3 亚微米带。通过扫描电子显微镜比较了 TiO2 纳米颗粒对纳米结构生长的催化效率和无催化剂生长。将涂覆催化剂和无催化剂的衬底并排排列，并同时进行外延生长，以确保在 PVD 炉中具有相同的生长条件。结果发现，催化剂提高了带的产量。以 28nm/min 的生长速率获得了非常长的带。经过 8 小时的生长，获得了长度约为 1mm、具有矩形横截面的带。通过原子力显微镜确定了厚度和宽度，其比值约为 1:10。使用能谱仪确定了化学成分为化学计量比的 Bi2Te3。温度相关的电导率测量表明，在低温下电导率具有特征性增加。20×10(5)S m(-1)的室温电导率表明样品质量优异。
