Preparation of LaXCoO3 (X = Mg, Ca, Sr, Ce) catalysts and their performance for steam reforming of ethanol to hydrogen

Abstract

Perovskite nanocomposite catalysts LaXCoO3 (X = Mg, Ca, Sr, or Ce; n(La):n(X) = 3:2) have been prepared by a citric acid-complexing method and used for steam reforming of ethanol (SRE), leading to hydrogen generation. The samples were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, N2 adsorption-desorption, and H2 temperature-programmed reduction. The effects of elemental substitution in the LaCoO3 perovskite were studied, and the catalytic performance and primary stability of the hydrogen production from SRE were investigated. In the highly substituted samples, only the Ce-doped sample was isolated as the pure perovskite phase. The presence of a Co3O4 phase in the Ca-doped or Sr-doped samples was beneficial for the reduction of the active Co component, while Sr-doped or Ce-doped samples showed good activity and stability. The sample incorporating Sr demonstrated better catalytic performance than those of other samples.