高インデックスファセットと高電気酸化活動を持つテトラヘクサヘドラルプラチナナノ結晶の合成
Na Tian1, Zhi-You Zhou, Shi-Gang Sun
1State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
Science (New York, N.Y.)
|May 5, 2007
まとめ
独特の四六角形のプラチナナノ結晶が合成されました. これらの新しい形状は,燃料電酸化のための触媒活性が著しく強化されていることを示しています.
科学分野:
- マテリアルサイエンス 材料科学
- 電気化学 電気化学について
- ナノテクノロジー ナノテクノロジー
背景:
- 高貴金属ナノ結晶 (NCs) は,通常,{111}と{100}の側面によって定義された形状を採用します.
- 一般的な形状には立方体,四面体,八面体などがあります.
研究 の 目的:
- 珍しい四六角形 (THH) 形を持つプラチナナノ結晶 (NC) を合成する.
- 小型の有機燃料の電気酸化のためのこれらのTHHNCの触媒的性質を調査する.
主な方法:
- グラス状の炭素に支えられたプラチナナノスフィアの電気化学処理は,正方形の波電位を用いて行われます.
- 結果となる単結晶THHNCの特徴.
主要な成果:
- シングル結晶THHプラチナNCの高収量合成.
- THH NCは24の高インデックスファセット ({730},{210},{520}) に囲まれており,高密度の原子ステップとぶら下がる結合を特徴としています.
- これらの表面は,優れた熱安定性 (800°Cまで) と化学安定性を示しています.
- 同等なPt表面積と比較して,キノコ酸とエタノールの電酸化のための触媒活性 (400%まで) が著しく向上しました.
結論:
- テトラヘクサヘドラルプラチナNCは,高度な触媒化のための有望なプラットフォームを提供します.
- THH NCの高インデックスの側面は,燃料電酸化における優れた触媒性能の鍵です.
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