単一の孤立したPt原子,原子群,およびナノ粒子による水素進化反応に対するサイズと基板の効果を調査する
Min Zhou1, Shujuan Bao1, Allen J Bard1
1Center for Electrochemistry, Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States.
Journal of the American Chemical Society
|April 25, 2019
まとめ
単一のプラチナ原子とナノ粒子は,電気化学的水素進化反応 (HER) を触媒する. プラチナの貯蔵量と基質 (ビスミュートまたは鉛) は,単一の原子が測定可能な活性を示し,HERの運動性に大きく影響します.
科学分野:
- 電気化学
- 材料科学
- カタリシス
背景:
- 電気化学的水素進化反応 (HER) は持続可能なエネルギー技術にとって極めて重要です.
- 個々の金属原子とナノ粒子の触媒的活性を理解することは 効率的な電触媒を設計する上で鍵となるものです
- プラチナ (Pt) はよく知られているHER触媒ですが,単一原子レベルでその活性についてはさらなる調査が必要です.
研究 の 目的:
- HERのビスミュート (Bi) と鉛 (Pb) の基板上の分離されたプラチナ堆積物のサイズに依存する触媒活性を調べる.
- 単一のPt原子とナノ粒子の電気化学的性能に対する基板材料の影響を明らかにする.
- HERを触媒化できるPt堆積物の最小サイズを決定する.
主な方法:
- BiおよびPb超微電子 (UMEs) に孤立したPt堆積物 (単一の原子からナノ粒子) を準備するための電解原子対原子塗装.
- 個々のPt堆積物におけるHERの電気触媒増幅を測定するボルト測定法.
- ボルトマモグラムのシミュレーションによる運動パラメータの推定,HERのVolmerステップを仮定します.
主要な成果:
- 単一の Pt 原子は HER に対して触媒的活性を示し,拡散を制限する電流の平原を示します.
- HERの運動は,BiとPbの両方の基板で約0. 2nmから4nmまでのPt積立半径で増加します.
- Bi基板の限定的なHER運動は,大量Ptに近いが,Pb基板の運動は著しく低い.
結論:
- 単離されたPt原子はHERに対して触媒的に活性である.
- HERに対するPt堆積物の触媒的活動は,大きさと基礎基質の両方に強く依存しています.
- ビズムは,プラチナ堆積物のHER運動を強化するために,鉛よりも効果的な基材として機能します.
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