Surface regulation of perovskite LaPd0.1Mn0.9O3 for improved toluene oxidation activity

Surface regulation is a crucial technique for improving catalytic performance in heterogeneous catalysis. Although perovskite oxides containing noble metals show good performance and excellent thermal stability, the encapsulation of noble metals in perovskite lattice restricts the exposure/usage of active sites. Herein, a method of high-temperature calcination coupling with selective dissolution was adopted to tune the physicochemical environment on the LaPd_0.1Mn_0.9O₃ catalyst surface. The X-ray diffraction (XRD) and Raman results reveal that more Pd species emerge on the surface by elevating the calcination temperature, resulting in improved catalytic toluene oxidation activity. A further acid-etching of the LPMO-900 catalyst can also boost catalytic performance, being attributed to the enhanced redox ability and abundant surface oxygen vacancies. In addition, the optimized catalyst also exhibits excellent resistance to sintering and water vapor. This study provides new avenues for the rational design of highly efficient perovskite-based catalysts.