Field emission from in situ-grown vertically aligned SnO2 nanowire arrays.

State Key Laboratory of Electronic Thin Film and Integrated Devices, School of Microelectronics and Solid-State Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China. .
Nanoscale Research Letters (Impact Factor: 2.52). 02/2012; 7:117. DOI: 10.1186/1556-276X-7-117
Source: PubMed

ABSTRACT Vertically aligned SnO2 nanowire arrays have been in situ fabricated on a silicon substrate via thermal evaporation method in the presence of a Pt catalyst. The field emission properties of the SnO2 nanowire arrays have been investigated. Low turn-on fields of 1.6 to 2.8 V/μm were obtained at anode-cathode separations of 100 to 200 μm. The current density fluctuation was lower than 5% during a 120-min stability test measured at a fixed applied electric field of 5 V/μm. The favorable field-emission performance indicates that the fabricated SnO2 nanowire arrays are promising candidates as field emitters.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Monocrystal SnO2 and Pd-SnO2 nanoribbons have been successfully synthesized by thermal evaporation, and novel ethanol sensors based on a single Pd-SnO2 nanoribbon and a single SnO2 nanoribbon were fabricated. The sensing properties of SnO2 nanoribbon (SnO2 NB) and Pd-doped SnO2 nanoribbon (Pd-SnO2 NB) sensors were investigated. The results indicated that the SnO2 NB showed a high sensitivity to ethanol and the Pd-SnO2 NB has a much higher sensitivity of 4.3 at 1,000 ppm of ethanol at 230°C, which is the highest sensitivity for a SnO2-based NB. Pd-SnO2 NB can detect ethanol in a wide range of concentration (1 ~ 1,000 ppm) with a relatively quick response (recovery) time of 8 s (9 s) at a temperature from 100°C to 300°C. In the meantime, the sensing capabilities of the Pd-SnO2 NB under 1 ppm of ethanol at 230°C will help to promote the sensitivity of a single nanoribbon sensor. Excellent performances of such a sensor make it a promising candidate for a device design toward ever-shrinking dimensions because a single nanoribbon device is easily integrated in the electronic devices.
    Nanoscale Research Letters 01/2014; 9(1):503. · 2.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Since the photo-electric response and charge carriers transport can be influenced greatly by the density and spacing of the ZnO nanorod arrays, controlling of these geometric parameters precisely is highly desirable but rather challenging in practice. Here, we fabricated patterned ZnO nanorod arrays with different density and spacing distance on silicon (Si) substrate by electron beam lithography (EBL) method combined with the subsequent hydrothermal reaction process. By using the EBL method, patterned ZnO seed layers with different areas and spacing distances were obtained firstly. ZnO nanorod arrays with different density and various morphologies were obtained by the subsequent hydrothermal growth process. The combination of EBL and hydrothermal growth process was very attractive and made us could control the geometric parameters of ZnO nanorod arrays expediently. Finally, the vertical transport properties of the patterned ZnO nanorod arrays were investigated through the micro probe station equipment and the I-V measurement results indicated that back-to-back Schottky contacts with different barriers height were formed in dark conditions. Under UV light illumination, the patterned ZnO nanorod arrays showed a high UV light sensitivity, and the response ratio was about 104. The controllable fabrication of patterned ZnO nanorod arrays and understanding for their photo-electric transport properties were helpful to improve the performance of nanodevices based on them.
    Nanoscale Research Letters 05/2012; 7(1):246. · 2.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Here we present a method to produce TiO2 nanocrystals coated by thin layer of graphitic carbon. The coating process was prepared via chemical vapor deposition (CVD) with acetylene used as a carbon feedstock with TiO2 used as a substrate. Different temperatures (400°C and 500°C) and times (10, 20, and 60 s) of reaction were explored. The prepared nanocomposites were investigated by means of transmission electron microscopy, Raman spectroscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy/diffuse reflectance spectroscopy and ultraviolet-vis (UV-vis)/diffuse reflectance spectroscopy. Furthermore, photocatalytic activity of the materials was investigated under visible and UV-vis light irradiation in the process of phenol decomposition. It was found that TiO2 modification with carbon resulted in a significant increase of photoactivity under visible irradiation and decrease under UV-vis light irradiation. Interestingly, a shorter CVD time and higher process temperature resulted in the preparation of the samples exhibiting higher activity in the photocatalytic process under visible light irradiation.
    Nanoscale Research Letters 04/2012; 7(1):235. · 2.52 Impact Factor

Full-text (2 Sources)

Available from
Jun 6, 2014