NO2 sensing properties of macroporous In2O3-based powders fabricated by utilizing ultrasonic spray pyrolysis employing polymethylmethacrylate microspheres as a template

SENSORS AND ACTUATORS B-CHEMICAL

卷:151

Article

Hyodo, Takeo¹  Hashishin, Takeshi²  Tamaki, Jun² 

[1] Nagasaki Univ, Grad Sch Sci & Technol, Dept Mat Sci & Engn, Fac Engn, Nagasaki 8528521, Japan

[2] Ritsumeikan Univ, Dept Appl Chem, Fac Sci & Engn, Kusatsu, Shiga 5258577, Japan

关键词: Gas sensor;    Indium oxide;    Ultrasonic spray pyrolysis;    Polymethylmethacrylate;    Macropores;   

DOI  :  10.1016/j.snb.2010.09.002

来源: Elsevier

【 摘 要 】

Macroporous (mp-) In2O3-based microspheres as a NO2 sensing material were prepared by the pyrolysis of atomized In(NO3)(3) aqueous solutions containing polymethylmethacrylate (PMMA) microspheres (150 nm in diameter) as a template. Well-developed spherical macropores (less than 100 nm in diameter) reflecting the morphology of the PMMA microsphere templates could be formed in the In2O3-based microspheres. The introduction of macropores into In2O3-based microspheres was very effective in improving the NO2 response of their thick films fabricated on an alumina substrate equipped with inter-digitated Pt electrodes (gap size: ca. 200 mu m) by screen-printing. In addition, the addition of a little amount of SnO2 to the mp-In2O3 microspheres not only lowered the resistance in air but also improved the NO2 response. NO2 sensing properties of non-stacked microspheres of the mp-In2O3 mixed with SnO2 were also investigated by utilizing nano-gap Au electrodes (gap size: ca. 200 nm). The non-stacked microspheres showed fast response and recovery speeds to NO2, because of better diffusion capability of NO2. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

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