Plasmonic structures and their applications in nanoelectrochemistry and single-molecule spectroelectrochemistry

我们的研究项目集中在金属纳米结构的发展及其在表面增强现象、化学传感和光谱电化学(SEC)中的应用。我们特别感兴趣的是在可见光范围内支持表面等离子激元(SP)激发(定域或传播SP)的纳米结构(等离子体结构)。最近，我们在等离子体方面取得了以下重要突破，这将导致单分子光谱电化学(SM-SEC)和纳米电化学新方法的发展：1)我们观察到吸附在电极表面的染料的单分子表面增强拉曼散射(SM-SERS)，并能够通过改变外加电位来控制单分子动力学；2)我们证明了金属薄膜中的纳米孔对吸附敏感，并支持增强光谱。我们建议利用这些突破，进一步扩大SM-SEC在氧化还原系统和蛋白质吸附方面的应用。我们还将使用“孔内”传感的概念来研究纳米孔内物种的电化学。纳米孔的光学性质将取决于吸附分子的氧化状态，这将是从纳米孔结构进行SEC的基础。还将探索使用成形纳米孔的表面增强型SEC。

Our research program is centered on the development of metallic nanostructures and their applications in surface-enhanced phenomena, chemical sensing and spectroelectrochemistry (SEC). We are particularly interested in nanostructures that support surface plasmon (SP) excitations (either localized or propagating SPs) in the visible range (plasmonic structures). Recently, we have achieved the following important breakthroughs in plasmonics that will culminate in the development of new approaches for single-molecule spectroelectrochemistry (SM-SEC) and nanoelectrochemistry: 1) We observed single-molecule surface-enhanced Raman scattering (SM-SERS) from dyes adsorbed on an electrode surface and were able to control the single-molecule dynamics by changing the applied potential; 2) We demonstrated that nanoholes in metal films are sensitive to adsorption and support enhanced spectroscopy. We propose to capitalize on these breakthroughs by further extending the application of SM-SEC to redox systems and protein adsorption. We will also use the concept of "in-hole" sensing to study the electrochemistry of species inside the nanoholes. The optical properties of the nanoholes will depend on the oxidation state of the adsorbed molecules, which will be the basis for the SEC from the nanohole structures. Surface-enhanced SEC using shaped nanoholes will also be explored.