Ultra-High-Speed Dynamics in Surface-Enhanced Raman Scattering
Ultra-High-Speed Dynamics in Surface-Enhanced Raman Scattering
复制标题
DOI：
10.1021/acs.jpcc.0c11150
复制
发表时间：
2021-03-08
影响因子：
3.7
通讯作者：
Brolo, Alexandre G.
中科院分区：
文献类型：
--
作者：
Lindquist, Nathan C.;Brolo, Alexandre G.
从这个角度来看，我们讨论了最近在表面增强拉曼散射（SERS）实验中与强度时间动力学相关的观察结果。SERS是一个成熟且高度活跃的研究领域，在分析和生物分析应用方面的潜力驱动着该技术的发展。然而，该效应的几个基本方面仍然挑战和吸引着该领域的研究人员。在这里，我们将重点关注最近的观察结果，即当实验以快速采集速率进行时，即使金属表面完全被吸附物覆盖，也可以看到强烈的SERS强度波动（SIFs）。有趣的是，SIF动态表明SERS活动的爆发只持续几百微秒，随后是更长的不活动时间。这种类型的行为已经从几种系统和结构中观察到，包括单金属纳米壳和纳米星，固定化胶体聚集体，镜面纳米粒子结构和金属包覆微球。这种多样性表明，动态行为是SERS效应的基本特征。在SERS热点的受限环境中，时间相关的原子重排被认为是驱动这些波动的主要机制。通过高速采集揭示的动态SERS行为将为原子重建和单分子与金属纳米环境相互作用的研究提供一个新的方向，其细节程度前所未有。
In this perspective, we discuss recent observations related to the temporal dynamics of intensities in surface-enhanced Raman scattering (SERS) experiments. SERS is a well-established and highly active research field, driven by the potential of the technique in analytical and bioanalytical applications. However, there are several fundamental aspects of the effect that still challenge and fascinate researchers in the area. Here we will focus on the recent observation that strong SERS intensity fluctuations (SIFs) are seen when experiments are performed at fast acquisition rates, even when the metal surface is completely covered by an adsorbate. Interestingly, the SIF dynamics indicate bursts of SERS activities that last only a few hundreds of microseconds, followed by a longer period of inactivity. This type of behavior has been observed from several systems and configurations, including single metallic nanoshells and nanostars, immobilized colloidal aggregates, nanoparticle-on-a-mirror configurations, and metal-coated microspheres. This diversity suggests that the dynamical behavior is a fundamental characteristic of the SERS effect. Time-dependent atomic rearrangements within the confined environment of the SERS hotspots are suggested as the main mechanism driving these fluctuations. The dynamical SERS behavior, revealed with high-speed acquisitions, should provide a new direction for the study of atomic reconstruction and single molecule interactions with metallic nanoenvironments with an unprecedented level of detail.