Preparation of H2 and LPG gas sensor

Among the various metal oxide additives tested, Ag2O is outstanding in promoting the sensing proper-ties of gamma-Fe2O3 element to H-2 in air. The gamma-Fe2O3 element loaded with 6 wt.% Ag2O is very sensitive to H, at 320 degreesC, while it is also sensitive to many other gases, especially C2H5OH. The element is highly sensitive and selective to H-2 and LPG, after it is modified with the surface-coat of Al2O3 containing 1.5 wt.% PtO. The response of this element to H-2 and C4H10 is rather rapid (only 4 and 6 s, respectively). and its resistance only changes 8.9% even when the ambient relative humidity varies broadly (from 10 to 98%). So the element is very useful to detect the leakage of coal gas or LPG in domestic appliances. (C) 2002 Elsevier Science B.V. All rights reserved.