ストレートされたLaNiO3ペロブスキートにおける強化された二機能酸素触媒
Jonathan R Petrie, Valentino R Cooper, John W Freeland1
1Advanced Photon Source, Argonne National Laboratory , Argonne, Illinois 60439, United States.
Journal of the American Chemical Society
|February 12, 2016
まとめ
圧縮圧力は,ペロブスキート酸化物の薄膜における酸素電解を著しく強化し,貴金属の性能を超える燃料電池とバッテリーの二機能活動を高めます.
科学分野:
- 材料科学
- 電気化学
- 表面科学
背景:
- ストレインエンジニアリングは,高貴な金属のフィルムの低温酸素電気触媒の最適化に不可欠です.
- ペロブスキートなどの移行金属酸化物の薄膜に対するストレスの触媒効果は,まだ十分に理解されていません.
研究 の 目的:
- 導電性ペロブスキートLaNiO3における酸素減少と酸素進化の反応に対する表層張りの影響を体系的に調査する.
- ペロブスキート酸化物におけるストレスの誘発による触媒強化の背後にあるメカニズムを理解する.
主な方法:
- LaNiO3薄膜のエピタキシアルストレイン
- 酸素還元反応 (ORR) と酸素進化反応 (OER) の電気触媒性能試験
- 電子構造,特に軌道分裂に対するストレスの影響の分析.
主要な成果:
- 圧縮ストレスはLaNiO3におけるORRとOER双機能活性の両方を有意に高めました.
- プレスされたペロブスキート触媒は,プラチナ (Pt) のような高貴金属触媒を上回った.
- ストレスを誘発した,例えば軌道分裂は,表面軌道不対称性をカスタマイズする重要な要因として識別された.
結論:
- エピタキシアルストレスは,ペロブスキート酸化物の電気触媒的活性を調節する強力なツールです.
- ストレス・エンジニアリングによるLaNiO3は,酸素の電気触媒に対する優れた二機能性能を示しています.
- この発見は,電子構造をストレスを介して操作することによって,先進的な酸化触媒の設計に関する洞察を提供します.
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