Non stoichiometric La1-yFeO3 perovskite-based catalysts as alternative to commercial three-way-catalysts? – Impact of Cu and Rh doping

A series of La1-yFe1-xCuxO3 catalysts with y = 0, 0.33 and x = 0, 0.17, 0.2 was prepared by a conventional sol-gel method. The catalytic activity in Three-Way Catalysis (TWC) of perovskite-based solids was compared to a commercial reference which contains Pd and Rh. The combination of Lanthanum-deficient synthesis and iron substitution by copper in LaFeO3 solid largely contributed to the enhancement of oxidation reactions especially for CO and propene whereas Rh doping activated the NO reduction in stoichiometric conditions. A better yield to nitrogen was obtained with much lower formation of ammonia at high temperature compared to the commercial reference. The characterization of perovskite-based catalyst (XRD, XPS, BET, H2-TPR) highlighted the specific properties due to Lanthanum-deficient synthesis and iron substitution by copper in LaFeO3.