Interaction between carbon oxides, hydrogen and Fe2O3 and An + 1FenO3n + 1 (A = Gd, Sr, n = 1, 2, …, ∞)

Resumo

The interaction between carbon oxides and hydrogen and surfaces of iron(III) oxide and A_{n + 1}Fe_nO_{3n + 1} (where A = Gd, Sr, and n = 1, 2, …, ∞ is the number of perovskite layers) complex oxides is studied for the first time by means of thermal programmed desorption. It is shown that carbon oxides are adsorbed in molecular form with the formation of carbonate–carboxylate complexes, and in dissociative form. The ratios of the adsorption forms of both oxides are determined by the structure of ferrites, the number of perovskite layers, and the valence state and coordinative saturation of iron. The presence of weakly and strongly bonded hydrogen forms is established, and it is suggested that hydrogen dissolves in the bulk of a perovskite.