Catalytic Coatings for Improving the Environmental Safety of Internal Combustion Engines

AK9 silumin samples (Al-Si) were treated by plasma electrolytic oxidation (PEO) in order to obtain surface oxide layer. These samples were not enough active as catalysts in CO oxidation (1% CO vol in air). Palladium activated samples were more active. Thus the temperature of 50% CO conversion for Pd/SiO2/Al-Si sample is T50 = 152 ̊C and T99 is 170 ̊C. According to IR spectroscopy and Raman spectroscopy as well as scanning electron microscopy data, the active layer of the most active sample Pd/SiO2/Al-Si presents by noncrystalline SiO2 with γ-alumina and palladium inclusions. the covering has of 10-20 nm Accordingly to atomic force microscopy data the roughness of surface layer is ∼ 10 – 20 nm.