Catalytically active composite materials with porous aluminum oxide matrix modified by γ-MnO2 nanoparticles

Abstract

Manganese dioxide has been deposited on the surface of an aluminum foil anodized in 3% solution of oxalic acid using the methods of thermal decomposition of manganese nitrate and potassium permanganate, as well as chemical synthesis, in the same solutions with intermediate drying and subsequent annealing. It has been demonstrated that the method of thermal decomposition of potassium permanganate is the most suitable for producing thermally stable “ultradispersed γ-MnO₂/nanostructured Al₂O₃/Al” composites. The produced composites are active in the reaction of oxidation of CO into CO₂ at temperatures above 180°C. Studies by means of the methods of scanning electron and atomic force microscopies have shown that the concentration and surface distribution of γ-MnO₂ particles depend on the morphological structure of aluminum oxide that is determined by conditions of the metal surface pretreatment and application of the pore broadening operation.