摘要
The CO response of Pd-doped tin oxide ceramics in both pellet and thick film versions is investigated. The porous thick film samples exhibit more sensitive CO response than pellet ones. A linear relation between CO concentration and sample resistance change is observed for samples doped with one wt.% PdCl 2 , while semi-logarithmic relations are obtained for samples doped with 2, 3 and 5 wt.% PdCl 2 . An optimum PdCl 2 content of 2 wt.% yields the best response to CO gas. The existence of the optimum catalyst content is attributed to a synergistic reaction. A possible mechanism for the CO sensing of tin oxide ceramics is explored. © 1988 The Metallurgical of Society of AIME.