Surface characterization and catalytic performance of La0.7Sr0.3MnO3+λ coating deposited by plasma spraying

A perovskite-type oxide (La0.7Sr0.3MnO3+λ) coating was deposited on a FeCrAlRE wire-mesh support by an air plasma spraying technique. The coated samples, as well as the powder samples prepared by a normal coprecipitating technique, were investigated for three-way catalytic performance and characterized by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET) and ultrasonic wave vibration tests. La0.7Sr0.3MnO3+λ coatings exhibited 95%, 48% oxidation rates of CO and C3H8, respectively, at 550 °C, while the activity for NO reduction decreased. Furthermore, the coating could be used as the support of noble metals to achieve excellent three-way catalytic activities. The light-off temperature (T50%) of CO, C3H8 and NO was 178 °C, 292 °C and 158 °C, respectively.