Sensitivity characteristics of ZnO-based semi-conductor gas sensors to etha
nol vapours have been investigated with lanthanum oxide and palladium. The
sensitivity of the sintered elements were promoted by the addition of La2O3
and Pd. Further, the sensor operating temperature was reduced with the nob
le metal. These elements have been tested for cross sensitivity for differe
nt gases and it has been confirmed that these are highly sensitive and sele
ctive for ethanol vapours at 175 degrees C in air atmosphere. The promoting
effect of the sensitivity of the sensor elements with lanthanum oxide seem
s to be related to the selectivity to oxidation of ethanol vapours. (C) 200
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