Advances in perovskite oxide catalysts for gaseous pollutant abatement: Design strategies, practical applications, and reaction mechanisms

Abstract

Perovskite oxides are a class of mixed metal oxides with a unique crystal structure and are widely employed for the removal of multiple gaseous pollutants. Owing to their structural versatility, nearly 90 % of the metal elements in the periodic table can be accommodated within the perovskite lattice. In this paper, the design strategy, application scenarios, and reaction mechanism of common perovskite oxides are systematically summarized, which can provide directions for optimizing the catalytic activity and removal performances, as well as for revealing the underlying mechanisms. To be specific, this review is organized into three main sections: (1) common design strategies for perovskite oxides, including morphology and structure construction, urea modulation, A-site nonstoichiometry, A-site substitution, B-site substitution, selective dissolution, interface and interaction; (2) applications of perovskite oxides in the abatement of gaseous pollutants, including CO, NO, VOCs and Hg⁰; (3) an overview of three catalytic oxidation mechanisms frequently observed in perovskite systems, namely the L-H, E-R, and MvK models. Finally, key findings and several research prospects are provided, with the aim of expanding the practical applications of perovskite oxides in flue gas purification.