通过内置的Pt--碳网状异构连接来开启-关闭光催化演变的切换
Leonardo Cognigni1, Thomas Gobbato1, Elisabetta Benazzi1
1Department of Chemical Sciences, University of Padova, Via Marzolo 1, Padova, Italy.
ChemSusChem
|October 18, 2024
概括
具有定义的N-doped位点的工程COF材料使控制的光催化演变成为可能. 基于异类素的COF-Naph-Tp由于Pt-N-C位点表现出卓越的性能,超过了NAPH模拟物.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 纳米技术纳米技术
背景情况:
- 碳材料的传统N-doping方法存在"黑子"的缺点,阻碍了定向设计.
- 在COF中,网状N兴奋剂提供了一个精确控制材料特性和催化功能的平台.
- 了解光电子,波段对齐和活性位点的相互作用对于优化光催化是至关重要的.
研究的目的:
- 为控制光催化演化 (PHE) 开发一个COF平台.
- 调查特定的N-doped站点及其协调环境在PHE监管中的作用.
- 为设计先进的碳基光催化剂制定结构反应性准则.
主要方法:
- 使用β-氨酸胺链接合成两个双COF平台 (COF-Naph-Tp和COF-IsoQ-Tp).
- 对COF结构,光电子特性和表面接口的描述.
- 光电化学测量和光催化H2进化实验.
- 进行X射线光电子光谱 (XPS) 和密度函数理论 (DFT) 计算以探测活性位点.
主要成果:
- 两种COF都表现出类似的结构和光电子特性,光收获长度高达700nm.
- COF-IsoQ-Tp显著提高了光电化学性能和PHE率 (11.3 mmol g-1 h-1).
- 不活跃的COF-Naph-Tp作为对照,突出显示了异类素部分的重要性.
- 在COF-IsoQ-Tp中,XPS和DFT证实了Pt-Npyridine-carbon异质连接的形成,作为活性位点.
结论:
- 在COF中的异类残留物对于形成Pt-Npyridine-碳活性位点至关重要,使得高效的光催化H2进化成为可能.
- 具有量身定制的金属--碳活性位点的工程化COF为设计高性能催化剂提供了途径.
- 这项工作为用于催化应用的碳基材料的合理设计提供了关键指南.
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