在环境条件下,原子分散的 Pt-N3C1 位点使素模型中的有效和选择性的电催化C-C键裂变成为可能
Tingting Cui1, Lina Ma2, Shibin Wang3
1Department of Chemistry, Tsinghua University, Beijing 100084, China.
Journal of the American Chemical Society
|June 17, 2021
概括
纳米管上的原子分散的--碳位点可以选择性地切割C-C键. 这种绿色电催化方法使用最小的,实现高产值的有价值的芳香化合物,提供一种可持续的树脂价值化方法.
科学领域:
- 催化剂
- 材料科学
- 绿色化学
背景情况:
- 碳-碳 (C-C) 键的选择性裂变对于生产有价值的芳香化合物至关重要.
- 电催化氧化在温和条件下提供一种可持续的木质素降解方法.
- 目前的电催化剂具有较低的选择性和C-C键裂变的低产量.
研究的目的:
- 开发一种高活性和选择性的电催化剂,用于素模型化合物的C-C键裂变.
- 调查原子分散金属部位的潜力,以有效地提升其价值.
主要方法:
- 通过聚合-碳化-静电吸附在添加的碳纳米管上合成原子分散的--碳位点 (Pt1/N-CNTs).
- 在环境条件下电催化氧化β-O-4素模型化合物.
- 密度功能理论 (DFT) 的计算以阐明催化机制.
主要成果:
- Pt1/N-CNT实现了99%的基质转化和81%的甲产量,优于现有的电催化剂.
- 与散装Pt电极和商业Pt/C相比,该催化剂的性能仅为0.41%重量.
- DFT计算表明,原子分散的 Pt-N3C1 位点通过基质中间路径促进了 Cα-Cβ 键裂变.
结论:
- 在N-CNT上,原子分散的Pt-N3C1位点在素模型中对Cα-Cβ键裂变具有高度活性和选择性.
- 这种电催化方法使得高效的素价值化能够显著减少贵金属的使用.
- 这些发现开辟了可持续和绿色的电化学转化成芳香化学品的新途径.
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