A high-surface-area La-Ce-Mn mixed oxide with enhanced activity for CO and C3H8 oxidation

A high-surface-area La-Ce-Mn mixed oxide was synthesized by citrate method, with further acid etching to dissolve the La 3   + ions in the lattice. The acid etching process efficiently improved the specific surface area, increased the ratios of Mn 4   + /Mn n   + , Ce 3   + /Ce n   + , O α /O tot , and enhanced the oxygen mobility of the catalyst, which were responsible for the superior catalytic performance. Compared to the pristine La 0.8 Ce 0.2 MnO 3   +   δ catalyst, the etched one could convert CO and C 3 H 8 more efficiently, with 90% conversion of CO and C 3 H 8 at only 73 and 196   °C, respectively. Such superior catalytic performance made it possible to be used for automotive emission control during cold-start period.