Fe,Pd Co-Incorporated LaCoO3 Perovskites: Modification of Thermal Stability and Catalytic Activity for Gasoline Vehicle Exhaust Purification

A series of LaCo0.95–xFexPd0.05O3 (x = 0, 0.1, 0.2, 0.3) perovskite-type catalysts have been prepared by a modified sol–gel method. Their structures and physicochemical properties have been studied by powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), the Brunauer–Emmett–Teller (BET) isotherm technique, and temperature-programmed reduction (TPR). Structural characterization showed that Fe had been successfully doped into the perovskite lattice and that Fe doping improves the stability of LaCo0.95Pd0.05O3. A study of the catalysts showed that aged samples maintain the perovskite structure. They all exhibited similar catalytic performance, which has been ascribed to the similar state of palladium at the surface of the catalysts. Of these as-prepared catalysts, the Fe-doped perovskites achieved better catalytic activities than LaCo0.95Pd0.05O3, and LaCo0.65Fe0.3Pd0.05O3 showed the optimal catalytic performance for vehicle emission purification.