Simple chemical solution coating and gas sensing properties of α-Fe2O3/chrysotile fibrous composites

alpha-Fe2O3/chrysotile fibrous composites were prepared by a simple chemical solution coating method for the gas sensitivity improvement of alpha-Fe2O3. X-ray diffraction (XRD) and atomic force microscope (AFM) analyses indicate that corundum-type alpha-Fe2O3 nanoparticles with a mean particle size similar to 20 nm are dense and well-proportioned on the surface of chrysotile fibers due to the mechanism that positively charged Fe(OH)(3) particles can be adsorbed onto the negatively charged chrysotile fibers in acidic liquids. The fabricated sensor devices were characterized for their electrical and gas sensing properties, it is found that the sensitivities of alpha-Fe2O3/chrysotile fibrous composites to H-2 and CH4 all increase by similar to 35% than those of the single alpha-Fe2O3 nanoparticles. Such simple coating treatment is an effective way in improving the continuities and gas sensing properties of nanogranular thick films. (C) 2012 Elsevier B.V. All rights reserved.