プラチナ表面における酸素アドスペーシスの移動性と反応性
Wei Wang1, Jie Zhang1, Fangfang Wang1
1State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China.
Journal of the American Chemical Society
|July 12, 2016
まとめ
燃料電池における触媒の無効化を防ぐには,プラチナ表面での酸素の移動性が重要です. この表面拡散の理解は,触媒の再活性化と中毒抵抗に役立ちます.
科学分野:
- 電気化学
- 表面科学
- 材料科学
背景:
- 燃料電池における主要な課題は,一酸化炭素 (CO) によってプラチナ (Pt) 触媒の無効化である.
- 酸素の吸附とPt上の移動性を理解することは,CO酸化に極めて重要です.
- 酸素添加物の表面移動性は,触媒の性能と長寿に影響する.
研究 の 目的:
- プラチナの表面上の酸素の移動性を調査する.
- 酸素アドスペーシスの表面拡散係数を決定する.
- CO酸化とPt触媒の抗毒性における酸素添加種の移動性の役割を明らかにする.
主な方法:
- ナノ電極と超マイクロ電極の技術を活用した.
- H2O吸収とCO反応による酸素アドスペーシスの観測された表面移動性.
- 拡散係数を決定するために,スキャンの速度に対する脱吸収電荷の依存性を分析した.
主要な成果:
- 酸素アドスペーシスの脱吸収電荷は,スキャンの速度の平方根の互換に比例する.
- 25 °Cで酸素アドスペーシスの表面拡散係数を (5.61 ± 0.84) × 10−10 cm2/sと決定した.
- CO酸化と酸素の表面移動に関連した2つの現在のピークを特定しました.
結論:
- 酸素アドスペーシスの表面移動性は,Pt触媒の抗毒および再活性化において重要な要因である.
- 観測された現象は,燃料電池のPt触媒の効率を維持するための洞察を提供します.
- この研究は,触媒プロセスにおける表面ダイナミクスの重要性を強調しています.
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