Lanthanum-Based Perovskite-Type Oxides La1−xCexBO3(B = Mn and Co) as Catalysts: Synthesis and Characterization

摘要

La1−xCexCoO3 (x = 0, 0.2, 0.4) and La1−xCexMnO3 (x = 0, 0.2) perovskite-type oxides were prepared by sol-gel process. Characterization techniques EDS, FTIR, XRD, BET, and XPS experiments were performed to survey the composition, bulk structure, and the surface properties of perovskites. The reduction behavior, thermal stability, and catalytic activity were studied by H2-TPR and catalytic performance. All synthesized samples showed well crystalline perovskite structure, 8–22 nm crystallite sizes, and SSA with 2–27 m2 g−1. The XRD results showed that the Ce substitution promoted the structural transformation for LaCoO3 from rhombohedral into cubic and for LaMnO3 no change in lattice geometry. Substitution with cerium (x = 0.2) showed smaller crystallite size, higher SSA, and the highest reducibility and catalytic activity for LaCoO3.