Zeng Linlin, Zhou Meng, Jin Rongchao
Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
Chemphyschem. 2024 Jul 2;25(13):e202300687. doi: 10.1002/cphc.202300687. Epub 2024 Apr 25.
Metal nanomaterials have been extensively investigated owing to their unique properties in contrast to bulk counterparts. Gold nanoparticles (e. g., 3-100 nm) show quasi-continuous energy bands, while gold nanoclusters (<3 nm) and complexes exhibit discrete energy levels and display entirely different photophysical properties than regular nanoparticles. This review summarizes the electronic dynamics of these three types of gold materials studied by ultrafast spectroscopy. Briefly, for gold nanoparticles, their electronic relaxation is dominated by heat dissipation between the electrons and the lattice. In contrast, gold nanoclusters exhibit single-electron transitions and relatively long excited-state lifetimes being analogous to molecules. In gold complexes, the excited-state dynamics is dominated by intersystem crossing and phosphorescence. A detailed understanding of the photophysical properties of gold nanocluster materials is still missing and thus calls for future efforts. The fundamental insights into the discrete electronic structure and the size-induced evolution in quantum-sized nanoclusters will promote the exploration of their applications in various fields.
与块状材料相比，金属纳米材料因其独特的性质而受到广泛研究。金纳米颗粒（例如，3 - 100纳米）显示出准连续能带，而金纳米团簇（<3纳米）和配合物则表现出离散的能级，并且与常规纳米颗粒相比具有完全不同的光物理性质。本综述总结了通过超快光谱研究的这三种金材料的电子动力学。简而言之，对于金纳米颗粒，其电子弛豫主要由电子与晶格之间的热耗散主导。相比之下，金纳米团簇表现出单电子跃迁，并且具有与分子类似的相对较长的激发态寿命。在金配合物中，激发态动力学主要由系间窜越和磷光主导。对金纳米团簇材料光物理性质的详细理解仍然缺失，因此需要未来的努力。对量子尺寸纳米团簇中离散电子结构和尺寸诱导演化的基本认识将促进其在各个领域应用的探索。
