Understanding Hot-Electron Generation and Plasmon Relaxation in Metal Nanocrystals: Quantum and Classical Mechanisms

By L. Besteiro, X. Kong, Zhiming M. Wang, Gregory Hartland, A. Govorov. 2017

302 citations recorded by the source corpus.

Generation of energetic (hot) electrons is an intrinsic property of any plasmonic nanostructure under illumination. Simultaneously, a striking advantage of metal nanocrystals over semiconductors lies in their very large absorption cross sections. Therefore, metal nanostructures with strong and tailored plasmonic resonances are very attractive for photocatalytic applications in which excited electrons play an important role. However, the central questions in the problem of plasmonic hot electrons are the number of optically excited energetic electrons in a nanocrystal and how to extract such electrons. Here we develop a theory describing the generation rates and the energy distributions of hot electrons in nanocrystals with various geometries. In our theory, hot electrons are generated due to surfaces and hot spots. As expected, the formalism predicts that large optically excited nanocrystals show the excitation of mostly low-energy Drude electrons, whereas plasmons in small nanocrystals involve mostly hig...

Subfields: Electronic, Optical and Magnetic Materials, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/e2dae53c1509f151d324a7ec3fc8cdbd108498a2