C-doped WO3 microtubes assembled by nanoparticles with ultrahigh sensitivity to toluene at low operating temperature

SENSORS AND ACTUATORS B-CHEMICAL

卷:155

Article

Ding, Xiaohu²  Zeng, Dawen^1,2  Zhang, Shunping¹  Xie, Changsheng¹ 

[1] Huazhong Univ Sci & Technol, Dept Mat Sci & Engn, NSSL, Wuhan 430074, Hubei, Peoples R China

[2] Huazhong Univ Sci & Technol, State Key Lab Mat Proc & Die & Mould Technol, Wuhan 430074, Hubei, Peoples R China

关键词: C-doped WO3;    Microtubes;    Toluene;    Ultrahigh sensitivity;    Low operating temperature;   

DOI  :  10.1016/j.snb.2010.11.030

来源: Elsevier

【 摘 要 】

Novel C-doped WO3 microtubes (MTs) were successfully synthesized by a facile infiltration and calcination process using the cotton fibers as templates. The prepared MTs were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), N-2 adsorption and desorption measurements and ultraviolet-visible spectroscopy. XPS spectra show the carbon was doped into the lattice of the WO3 phase, resulting in a decrease of the band gap of the C-doped WO3 MTs from 2.45 eV to 2.12 eV. Moreover, the WO3 MTs were assembled by nanoparticles in size of ca. 40 nm and had larger specific surface area (21.3 m(2)/g) due to existence of meso/macro-pores inside them. At low operating temperature of 90 degrees C, the gas sensor based on the C-doped WO3 MTs had a detected limit of 50 ppb to the toluene gas (response of 2.0). The enhancement of toluene sensing performance of C-doped WO3 MTs was attributed to a larger surface area and higher porosity, which arises from its unique MTs. Furthermore, the band gap reduction and a new intragap band formation for C-doped WO3 MTs were proposed as the reason for the decrease in optimal operating temperature. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

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