Perovskite catalysts for carbon monoxide oxidation: a critical review of activity-associated parameters, mechanisms, and deactivation

Abstract

Abstract: Although catalytic CO oxidation has been investigated since the early 20th century, it remains an important topic due to stricter environmental regulations. Despite the fact that precious metal-based catalysts have been commercially available for three-way catalysts, catalytic CO oxidation in industrial flue gas has been hampered due to high costs, complex flue-gas compositions and severe operating conditions. Perovskite catalysts have shown great potential for CO oxidation due to their tunable redox properties, high thermal stability, and exceptional oxygen mobility. The activity of perovskite catalysts for CO oxidation is influenced by B-site composition, A-site substitution, support condition, and synthesis route, but the relative importance of these descriptors remains difficult to disentangle across the heterogeneous literature. Therefore, a comprehensive review dedicated to resolving these complexities is still urgently needed. Here, we provide a critical review that combines an exploratory cross-study analysis of reported T50 values with a mechanistic discussion of redox chemistry, oxygen-defect properties, and deactivation pathways. This review not only systematizes the current understanding of perovskite catalysts for CO oxidation but also provides valuable insights for designing next-generation catalytic systems with enhanced activity and durability.