原子分散型 Pt-N3C1環境条件下における効率的かつ選択的な電触媒C-C結合割れを可能にする場所
Tingting Cui1, Lina Ma2, Shibin Wang3
1Department of Chemistry, Tsinghua University, Beijing 100084, China.
Journal of the American Chemical Society
|June 17, 2021
まとめ
ナノチューブの原子的に分散したプラチナ-窒素-炭素部位は,選択的なリグニンC-C結合分裂を可能にします. この緑の電気触媒法では,価値ある芳香化合物の高い収量を得ることができ,プラチナを最小限に使用し,リグニンの評価に持続可能なアプローチを提供します.
科学分野:
- キャタリシス
- 材料科学
- 緑の化学
背景:
- リグニンの炭素-炭素 (C-C) 結合の選択的分裂は,貴重な芳香化合物の生成に不可欠である.
- 電気触媒による酸化は,穏やかな条件下でリグニンの分解のための持続可能な方法を提供します.
- 現在の電気触媒は,C−C結合分裂の選択性と低生産性を示しています.
研究 の 目的:
- リグニンモデル化合物のC−C結合分裂のための高活性で選択的な電気触媒を開発する.
- 効率的なリグニン価値化のための原子的に分散した金属の場所の可能性を調査する.
主な方法:
- 窒素ドーピングされた炭素ナノチューブ上の原子分散プラチナ-窒素-炭素サイト (Pt1/N-CNTs) の合成は,ポリメリゼーション-炭化-静電吸附による.
- 環境条件下でβ-O-4リグニンモデル化合物の電気触媒酸化.
- 触媒メカニズムを解明するための密度関数理論 (DFT) の計算.
主要な成果:
- Pt1/N-CNTは99%の基質変換と81%のベンザルデヒド出力を達成し,既存の電解剤を上回った.
- 触媒は,散発型Pt電極と商用Pt/Cと比較して,わずか0.41%の重量で優れた性能を示した.
- DFTの計算は,原子的に分散したPt-N3C1サイトが,Cα-Cβ結合の分裂を,中間基経路を通じて促進することを示した.
結論:
- N-CNTの原子的に分散したPt-N3C1サイトは,リグニンモデルにおけるCα-Cβ結合分裂に高度に活性化し,選択的である.
- この電気触媒的アプローチは,貴金属の使用量を大幅に削減して効率的なリグニン価値化を可能にします.
- この発見は,リグニンをアロマティックな化学物質に持続可能な 緑の電気化学的変換のための新しい道を開きます.
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