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Effect of Ba Content on the Activity of La_1-x Ba _x MnO₃ Towards the Oxygen Reduction Reaction.

ABSTRACT: The electrocatalytic activity of La_1-x Ba _x MnO₃ nanoparticles towards the oxygen reduction reaction (ORR) is investigated as a function of the A-site composition. Phase-pure oxide nanoparticles with a diameter in the range of 40 to 70 nm were prepared by using an ionic liquid route and deposited onto mesoporous carbon films. The structure and surface composition of the nanoparticles are probed by XRD, TEM, EDX, and XPS. Electrochemical studies carried out under alkaline conditions show a strong correlation between the activity of La_1-x Ba _x MnO₃ and the effective number of reducible Mn sites at the catalysts layer. Our analysis demonstrates that, beyond controlling particle size and surface elemental segregation, understanding and controlling Mn coordination at the first atomic layer is crucial for increasing the performance of these materials.

SUBMITTER: Gobaille-Shaw GPA

PROVIDER: S-EPMC6146913 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Effect of Ba Content on the Activity of La1-x Ba x MnO3 Towards the Oxygen Reduction Reaction.

Gobaille-Shaw Gael P A GPA Celorrio Veronica V Calvillo Laura L Morris Louis J LJ Granozzi Gaetano G Fermín David J DJ

ChemElectroChem 20180406 14

The electrocatalytic activity of La1-x Ba x MnO3 nanoparticles towards the oxygen reduction reaction (ORR) is investigated as a function of the A-site composition. Phase-pure oxide nanoparticles with a diameter in the range of 40 to 70 nm were prepared by using an ionic liquid route and deposited onto mesoporous carbon films. The structure and surface composition of the nanoparticles are probed by XRD, TEM, EDX, and XPS. Electrochemical studies carr ...[more]

PMID: 30263882

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