PURPOSE: To perform quantity production of an element and mount the element also to an existing internal-combustion engine, by secondarily mounting the element, previously and separately worked and held with a catalyst, to a non-slided part of the internal wall of an internal-combustion engine and displaying a catalytic function.

CONSTITUTION: Temperature of a catalytic layer is held to a controlled condition at 500°C or less for an external wall surface cooled internal-combustion engine and about 800°C for a heat insulated internal-combustion engine, and oxidizing reaction of contact low temperature is caused to hydrocarbon of an anti-inflammatory layer formed on internal wall surfaces 21, 22 to burn while stirring a fuel mixture in the vicinity. Then the reaction heat is propagated to a fuel mixture compressed in combustion chambers 11, 12 and guided to efficient combustion reaction to efficiently perform combustion without causing the misfiring also of a lean mixture. A catalytic layer 5 consisting of a catalyst not necessary to endure high temperature at least 1,000°C is secured to the surface of an element mounted to the surfaces 21, 22 of a non-slided part. Metallic powder of platinum system is used as the catalyst and welded under pressure to the surface of the element by the method of hot press or the like.