Pt5Gdは,酸素電還元のための高度に活性で安定した触媒である.
María Escudero-Escribano1, Arnau Verdaguer-Casadevall, Paolo Malacrida
1Center for Individual Nanoparticle Functionality, Department of Physics, Building 312, Technical University of Denmark (DTU), DK-2800 Lyngby, Denmark.
Journal of the American Chemical Society
|September 25, 2012
まとめ
プラチナ-ガドリニウム (Pt(5) Gd) 触媒は,純粋なプラチナと比較して,酸素還元反応 (ORR) の活性が5倍に増加することを示しています. 圧縮圧延によるこの強化された活動により,Pt(5) Gdは燃料電池触媒の有望な材料となっています.
科学分野:
- 電気化学 電気化学について
- マテリアルサイエンス 材料科学
- カタリシス カタリシス カタリシス
背景:
- 効率的な電気触媒の開発は,燃料電池技術の進歩に不可欠です.
- プラチナ基の合金は,酸素還元反応 (ORR) の触媒として広く研究されています.
研究 の 目的:
- 酸素還元反応 (ORR) のためのプラチナ-ガドリニウム (Pt(5) Gd) の活性と安定性を調査する.
- Pt(5) Gd.の触媒性能の強化の背後にあるメカニズムを解明する.
主な方法:
- 電気化学測定について
- 角解像度X線光電子スペクトロスコピー (AR-XPS)
- 密度関数理論 (DFT) の計算
主要な成果:
- スプッターで浄化されたPt(5) Gdは,0.9Vで純粋なPtと比較してORR活性が5倍増加した.
- AR-XPSは,電気化学的試験の後,Pt(5) Gdにプラチナのオーバーレイヤの形成を明らかにしました.
- 強化された活動は,触媒構造内の圧縮性ストレスの効果に起因する.
結論:
- Pt(5) Gdは,ORRの活動が著しく強化され,高い安定性を示しています.
- これらのバイメタリック電気触媒は,将来の燃料電池カソッドアプリケーションに大きな希望を示しています.
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