Wu Jyh Ming
Department of Material Science and Engineering, Feng Chia University, 100 Wenhwa Rd., Seatwen, Taichung 40724, Taiwan.
J Nanosci Nanotechnol. 2012 Feb;12(2):1434-9. doi: 10.1166/jnn.2012.4659.
Sn-doped rutile TiO2 nanowires were synthesized by a thermal reactive evaporation route. Field emission scanning electron microscopy (FESEM) imaging reveals that the Sn-doped TiO2 nanowires exhibited diameters of 80-150 nm and 2-3 microns in length. High-resolution transmission electron microscopy (HRTEM) imaging makes it possible to observe that Sn-doped TiO2 nanowires show a certain lattices fringe of approximately 0.32 nm, which demonstrates that the nanowires are single crystalline with rutile structure and grow along the [110] axis. Cathodoluminescence (CL) reflected that on the surface of Sn-doped TiO2 nanowires, many oxygen vacancies and defect states were formed during the crystal growth. These defect states raised a broad emission peak around the red-orange band. The ethanol sensing properties of Sn-doped rutile TiO2 nanowires at a temperature of 190 degrees C for the ethanol concentrations of 50, 100, 150, 200, 400, 500, and 600 ppm, correspond to the sensor' sensitivity of 7, 12, 18, 19, 23, and 26%, respectively. The sensitivity increased with an increase in the ethanol concentration. As-synthesized TiO2 nanowires revealed a turn-on field, approximately 5.1 V/microm, at a current density of 1 microAcm(-2).
通过热反应蒸发法合成了掺锡金红石型TiO₂纳米线。场发射扫描电子显微镜（FESEM）成像显示，掺锡TiO₂纳米线的直径为80 - 150 nm，长度为2 - 3微米。高分辨率透射电子显微镜（HRTEM）成像使得观察到掺锡TiO₂纳米线呈现出约0.32 nm的特定晶格条纹成为可能，这表明纳米线是具有金红石结构的单晶，并沿[110]轴生长。阴极发光（CL）表明，在掺锡TiO₂纳米线表面，晶体生长过程中形成了许多氧空位和缺陷态。这些缺陷态在红橙色波段周围产生了一个宽发射峰。掺锡金红石型TiO₂纳米线在190℃下对乙醇浓度为50、100、150、200、400、500和600 ppm时的乙醇传感特性，对应的传感器灵敏度分别为7%、12%、18%、19%、23%和26%。灵敏度随乙醇浓度的增加而增加。合成的TiO₂纳米线在电流密度为1 μAcm⁻²时显示出约5.1 V/μm的开启场。
