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Activating Molecules, Ions, and Solid Particles with Acoustic Cavitation
Published on: April 11, 2014
ハロゲン誘発によるプラチナの腐食
Enrico Doná1, Michael Cordin, Clemens Deisl
1Institute of Physical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria.
Journal of the American Chemical Society
|February 11, 2009
まとめ
塩素とプラチナ (Pt) の表面の相互作用は,表面の侵食とPtCl(4) の形成を引き起こします. 解熱は欠陥を修復し,電解質堆積の結果に似た順番の付加層を作成します.
科学分野:
- 表面科学とは,地表科学である.
- 材料化学 材料化学について
- 物理化学 物理化学
背景:
- アドソーベートと表面の相互作用を理解することは,触媒と材料科学にとって極めて重要です.
- プラチナ表面は,触媒に広く使用されており,ハロゲンとの反応性が重要な研究分野となっています.
研究 の 目的:
- 超高真空 (UHV) 条件下で,塩素 (Cl) とプラチナ (Pt) の表面 (Pt) の相互作用を調査する.
- Clの吸収とPtの圧縮で生じる構造的,化学的変化を明らかにする.
主な方法:
- スキャントンネル顕微鏡 (STM) は,原子スケールの表面イメージングを目的としています.
- 表面構造分析のための低エネルギー電子 difraktion (LEED) について.
- 温度プログラムされた脱吸収 (TPD) で,脱吸収運動を研究する.
- 理論的な洞察のための密度関数理論 (DFT) 計算.
主要な成果:
- Clの0.5個までの単層 (ML) は,Pt{110}上で安定したアドソルベート構造を形成する.
- Clをより高いカバーに圧縮すると,Pt原子の侵食が誘発され,PtCl ((4)) ペンタマーが形成されます.
- 解熱はPt表面の欠陥を修復し,長距離に並べられたPtCl(4)/Cl/Pt(110) 付加層を形成する.
- COとの共吸収により,揮発性産物なしでPtCl(4) の形成が始まります.
- ブロム (Br) は腐食活動が低く,Pt表面は無傷のままです.
結論:
- 塩素はPt(110) の表面構造を著しく変化させ,欠陥形成とPtCl(4) の種に繋がります.
- 解熱後の観察された付加層構造は,電解質の堆積によって形成されたものと類似しています.
- ブロミンとの比較研究は,プラチナ表面のハロゲンの反応性の違いを強調しています.
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