Subsurface A-site vacancy activates lattice oxygen in perovskite ferrites for methane anaerobic oxidation to syngas.

ABSTRACT: Tuning the oxygen activity in perovskite oxides (ABO₃) is promising to surmount the trade-off between activity and selectivity in redox reactions. However, this remains challenging due to the limited understanding in its activation mechanism. Herein, we propose the discovery that generating subsurface A-site cation (La_sub.) vacancy beneath surface Fe-O layer greatly improved the oxygen activity in LaFeO₃, rendering enhanced methane conversion that is 2.9-fold higher than stoichiometric LaFeO₃ while maintaining high syngas selectivity of 98% in anaerobic oxidation. Experimental and theoretical studies reveal that absence of La_sub.-O interaction lowered the electron density over oxygen and improved the oxygen mobility, which reduced the

SUBMITTER: He J 

PROVIDER: S-EPMC11208437 | biostudies-literature | 2024 Jun

REPOSITORIES: biostudies-literature