Plasmon-Mediated Chemical Reactions on Nanostructures Unveiled by Surface-Enhanced Raman Spectroscopy.,Accounts of Chemical Research

当前位置： X-MOL 学术 › Acc. Chem. Res. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Plasmon-Mediated Chemical Reactions on Nanostructures Unveiled by Surface-Enhanced Raman Spectroscopy.
Accounts of Chemical Research ( IF 16.4 ) Pub Date : 2019-09-18 , DOI: 10.1021/acs.accounts.9b00280
Chao Zhan ₁ , Xue-Jiao Chen ₂ , Yi-Fan Huang ₁ , De-Yin Wu ₁ , Zhong-Qun Tian ₁

Affiliation

Surface plasmons (SPs) originating from the collective oscillation of conduction electrons in nanostructured metals (Au, Ag, Cu, etc.) can redistribute not only the electromagnetic fields but also the excited carriers (electrons and holes) and heat energy in time and space. Therefore, SPs can engage in a variety of processes, such as molecular spectroscopy and chemical reaction. Recently, plenty of demonstrations have made plasmon-mediated chemical reactions (PMCRs) a very active research field and make it as a promising approach to facilitate light-driven chemical reactions under mild conditions. Concurrently, making use of the same SPs, surface-enhanced Raman spectroscopy (SERS) with a high surface sensitivity and energy resolution becomes a powerful and commonly used technique for the in situ study of PMCRs. Typically, various effects induced by SPs, including the enhanced electromagnetic field, local heating, excited electrons, and excited holes, can mediate chemical reactions. Herein, we use the para-aminothiophenol (PATP) transformation as an example to elaborate how SERS can be used to study the mechanism of PMCR system combined with theoretical calculations. First, we distinguish the chemical transformation of PATP to 4,4'-dimercaptoazobenzene (DMAB) from the chemical enhancement mechanism of SERS through a series of theoretical and in situ SERS studies. Then, we focus on disentangling the photothermal, hot electrons, and "hot holes" effects in the SPs-induced PATP-to-DMAB conversion. Through varying the key reaction parameters, such as the wavelength and intensity of the incident light, using various core-shell plasmonic nanostructures with different charge transfer properties, we extract the key factors that influence the efficiency and mechanism of this reaction. We confidently prove that the transformation of PATP can occur on account of the oxygen activation induced by the hot electrons or because of the action of hot holes in the absence of oxygen and confirm the critical effect of the interface between the plasmonic nanostructure and reactants. The products of these two process are different. Furthermore, we compare the correlation between PMCRs and SERS, discuss different scenario of PMCRs in situ studied by SERS, and provide some suggestions for the SERS investigation on the PMCRs. Finally, we comment on the mechanism studies on how to distinguish the multieffects of SPs and their influence on the PMCRs, as well as on how to power the chemical reaction and regulate the product selectivity in higher efficiencies.

中文翻译：

表面增强拉曼光谱揭示的纳米结构上的等离子介导化学反应。

源于纳米结构金属（Au，Ag，Cu等）中传导电子的集体振荡的表面等离激元（SP）不仅可以重新分布电磁场，还可以在时空中重新分布激发的载流子（电子和空穴）和热能。因此，SP可以参与多种过程，例如分子光谱学和化学反应。最近，大量的演示使等离激元介导的化学反应（PMCR）成为一个非常活跃的研究领域，并使其成为在温和条件下促进光驱动化学反应的有前途的方法。同时，利用相同的SP，具有高表面灵敏度和能量分辨率的表面增强拉曼光谱（SERS）成为原位研究PMCR的有力且常用的技术。通常，SP引起的各种影响（包括增强的电磁场，局部加热，受激电子和受激空穴）可以介导化学反应。在此，我们以对氨基硫酚（PATP）转化为例，结合理论计算，阐述如何利用SERS研究PMCR体系的机理。首先，我们通过一系列理论和原位SERS研究，从SERS的化学增强机理中区分出PATP向4,4'-二巯基偶氮苯（DMAB）的化学转化。然后，我们重点研究在SPs诱导的PATP到DMAB转换中解开光热，热电子和“热空穴”效应。通过改变关键的反应参数，例如入射光的波长和强度，我们使用具有不同电荷转移特性的各种核-壳等离激元纳米结构，我们提取了影响该反应效率和机理的关键因素。我们有把握地证明，由于热电子引起的氧活化或由于在没有氧的情况下热空穴的作用，PATP的转化可以发生，并证实了等离子体纳米结构与反应物之间界面的关键作用。这两个过程的产品是不同的。此外，我们比较了PMCR和SERS之间的相关性，讨论了SERS就地研究过的PMCR的不同情况，并为SERS研究PMCR提供了一些建议。最后，我们对有关如何区分SP的多重效应及其对PMCR的影响的机理研究进行评论，

更新日期：2019-09-18

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南