Light-excited energetic electrons, or so-called hot electrons (HEs), in plasmonic metal nanostructures have received much attention in the past few years. Plasmonic metal nanostructures, acting as light absorbers with higher efficiency and adjustability than dye molecules and inorganic semiconductors, can generate HEs under specific light conditions. However, the overall efficiency of the plasmonic systems remain unsatisfactory. Therefore, it is important to study the generation and transfer processes of plasmon-induced HEs, which are necessary for efficient plasmon-enhanced applications. In this review, we summarize the basic concepts and mechanisms of HE generation and transportation, then highlight the use of in situ surface-enhanced Raman spectroscopy (SERS) as a probe for HE-induced chemical reactions. We also discuss the opportunities and remaining challenges in promoting fundamental understanding of, and practical applications for, HEs.

在过去几年中，等离子体金属纳米结构中的光激发高能电子或所谓的热电子（HE）受到了广泛关注。等离子体金属纳米结构，比染料分子和无机半导体具有更高的效率和可调节性，可以在特定的光照条件下生成HE。但是，等离子体系统的整体效率仍然不能令人满意。因此，重要的是研究等离激元诱导的HE的生成和转移过程，这对于有效的等离激元增强应用是必需的。在这篇综述中，我们总结了HE产生和运输的基本概念和机制，然后重点介绍了原位使用表面增强拉曼光谱（SERS）作为HE诱导化学反应的探针。我们还将讨论在促进对HE的基本了解和实际应用方面的机会和尚存的挑战。