電気化学界面でのプロペンの酸化の反応機構と選択性調整
Xiao-Chen Liu1, Tao Wang1, Zhi-Ming Zhang1
1State Key Laboratory of Physical Chemistry of Solid Surfaces, Tan Kah Kee Innovation Laboratory, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
Journal of the American Chemical Society
|November 8, 2022
まとめ
プロペンの電気化学的変換は,反応メカニズムを理解することで進みます. PdO/C触媒は,表面酸素によるPd/Cよりもプロペングリコール生成の効率が高くなります.
科学分野:
- 電気化学
- キャタリシス
- 化学工学
背景:
- プロペンの電気化学的変換は再生可能エネルギーを用いて 商品化化学物質への持続可能な経路を提供します
- プロペンの電気酸化のための効率的な電気触媒の開発には,分子レベルの反応機構を理解することが不可欠です.
- 電気化学的条件下での固体/液体界面でのプロペンの酸化のメカニズムは,熱触媒的プロセスと比較して,まだ理解されていない.
研究 の 目的:
- 炭素 (PdO/C) と炭素 (Pd/C) のパラジウムに対するプロペンの電気酸化反応のメカニズムを調査し解明する.
- PdO/CとPd/Cの反応経路の主要な違いを特定し,電解性能を比較する.
主な方法:
- 反応中介物質と経路を研究するために,電気化学的インシット減弱総反射フーリエ変換赤外線光譜法 (ATR-FTIR) が使用された.
- 酸化過程における表面酸素の役割を検証するために,H218O同位素編集実験が使用された.
主要な成果:
- プロペンの脱水は0.80V以上の電位で発生する.
- 異なる吸収構成 (PdOのμ-CCHCH3とPdのμ3-η2-CCHCH3) が特定されました.
- PdO/CはPd/Cと比較してプロペングリコール生産の周回頻度が3倍高いことが示され,これは直接酸化を促進する高表面酸素含有量によるものである.
結論:
- この研究は,熱触媒と比べると,電気化学的環境でのプロペンの電気酸化の反応経路が異なることを明らかにした.
- PdO/Cの表面酸素は,吸収されたプロペンの中間物質の酸化に直接参加することによって,触媒活性を強化する上で重要な役割を果たします.
- これらの発見は,プロペンの効率的な電気酸化のための高度な電気触媒の設計のための洞察を提供します.
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