Abstract: This invention provides a composition comprising a mixture or a fired product of a material of the general formula Sr.sub.(1+x)/2 La.sub.(1-x)/2 Co.sub.1-x Me.sub.x O.sub.3-.delta. (wherein Me: at least one of Fe, Mn, Cr and V; O.ltoreq.x.ltoreq.1; .delta.: loss of oxygen) and SrMeO.sub.3 (wherein Me: at least one of Ti, Zr and and Hf), and a catalyst and a multi-functional sensor using such composition. With this composition it is possible to improve the catalytic performance for cleaning exhaust gas grom combusters or internal combustion engines and to improve sensitivity or response characteristics of the sensors for detecting stoichiometric composition.

Abstract: This invention provides a composition comprising a mixture or a fired product of a material of the general formula Sr.sub.(1+x)/2 La.sub.(1-x)/2 Co.sub.1-x Me.sub.x O.sub.3-.delta. (wherein Me: at least one of Fe, Mn, Cr and V; 0.ltoreq.x.ltoreq.1; .delta.: loss of oxygen) and SrMeO.sub.3 (wherein Me: at least one of Ti, Zr and and Hf), and a catalyst and a multi-functional sensor using such composition. With this composition it is possible to improve the catalytic performance for cleaning exhaust gas from combusters or internal combustion engines and to improve sensitivity or response characteristics of the sensors for detecting the stoichiometric composition.