Li Zhandong, Kurouski Dmitry
Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, USA.
Nanoscale. 2021 Jul 15;13(27):11793-11799. doi: 10.1039/d1nr02478g.
We present a label-free approach that is based on tip-enhanced Raman spectroscopy (TERS) for a direct in situ assessment of the molecular reactivity in plasmon-driven reactions. Using this analytical approach, named cargo-TERS, we investigate the relationship between the chemical structure of aromatic halides and the catalytic probability of the Suzuki-Miyaura coupling reaction on gold-palladium bimetallic nanoplates (Au@PdNPs). We demonstrate that cargo-TERS can be used to quantify the yield of biphenyl-4,4'-dithiol (BPDT), the product of the coupling reaction. Our results also show that the halide reactivity decreases from bromo through chloro to fluorohalides. Finally, we employ this novel imaging technique to unravel the nanoscale reactivity and selectivity of Au@PdNPs. We find that the edges and corners of these nanostructures exhibit the highest catalytic reactivity, while the flat terraces of Au@PdNPs remain catalytically inactive.
我们提出了一种基于针尖增强拉曼光谱（TERS）的无标记方法，用于直接原位评估等离子体驱动反应中的分子反应活性。使用这种名为“货物-TERS”的分析方法，我们研究了芳基卤化物的化学结构与金-钯双金属纳米板（Au@PdNPs）上铃木-宫浦偶联反应的催化概率之间的关系。我们证明“货物-TERS”可用于量化偶联反应产物4,4'-二硫醇联苯（BPDT）的产率。我们的结果还表明，卤化物反应活性从溴化物到氯化物再到氟化物逐渐降低。最后，我们采用这种新型成像技术来揭示Au@PdNPs的纳米级反应活性和选择性。我们发现这些纳米结构的边缘和角落表现出最高的催化反应活性，而Au@PdNPs的平坦表面则保持催化惰性。
