J Mater Sci Technol ›› 2008, Vol. 24 ›› Issue (04): 667-674.

• Research Articles • Previous Articles    

Porous Cube-like In2O3 Nanoparticles and Their Sensing Characteristics toward Ethanol

Chih-Chia HUANG, Chen-Sheng YEH   

  • Received:2007-09-22 Revised:2008-08-20 Online:2008-07-28 Published:2009-10-10
  • Contact: Chen-Sheng YEH

Abstract: Porous cube-like crystalline In2O3 nanoparticles with an average diagonal length of 34.8 nm were fabricated by a laser ablation-reflux process to form In(OH)3, followed by a calcination treatment to yield porous In2O3. HRTEM (high-resolution transmission electronic microscopy), XRD (X-ray diffraction), BET (Brunauer-Emmett-Teller), and XPS (X-ray photoelectron spectroscopy) analysis were used to characterize their crystalline structures, grain sizes, surface areas, and surface compositions. The as-prepared porous indium oxides were tested for their sensing properties toward ethanol. Non-porous In2O3 nanopowder (about 40 nm) was also examined in order to compare the results with the as-prepared porous In2O3 nanomaterials. The porous In2O3 exhibited much better performance than that of non-porosus In2O3, and showed enhanced sensitivity with a lower detection limit than other reported In2O3-based materials when exposed to ethanol. Good gas sensitivity and linear behavior as a function of ethanol concentration were observed in the porous In2O3 nanoparticles.

Key words: In2O3, Porosity, Nanoparticles, Gas sensor