A new in situ methodology for the quantification of the oxygen storage potential in perovskite-type materials

Abstract

A well known perovskite-type material, LaFeO₃, was prepared by citrate–nitrate auto-combustion synthesis and used to formulate a new in situ approach for the analytical evaluation of the redox properties of this class of material. Carbon monoxide was used as a reducing agent-probe, while molecular oxygen was used as an oxidizing agent-probe. In situ FTIR spectroscopy was applied for a qualitative characterization of the interaction probe-material, and microgravimetry was used in order to quantify the extent of the interaction. The results obtained indicated that simple molecules, such as CO and O₂, are able to define the redox properties of the material without inducing any important modification as in the case of the more classical temperature-programmed reduction and oxidation methods. The described procedure can be successfully applied for the evaluation of the oxygen mobility/availability and storage potential of other perovskite-type materials.