Related Experiment Video
Updated: Jan 27, 2026

Synthesis of Near-Infrared Emitting Gold Nanoclusters for Biological Applications
Published on: March 22, 2020
Room-Temperature Delayed Fluorescence of Gold Nanoclusters in Zinc-Mediated Two-Dimensional Crystalline Assembly
Abstract:
We report that complexation-reaction-mediated two-dimensional crystalline assembly of gold (Au14) nanoclusters (NCs) exhibits room-temperature delayed fluorescence at 605 nm, with an unprecedented long lifetime of 0.5 ms and an exceptionally high quantum yield of 19.1 ± 0.9%. Interestingly, the as-synthesized Au NCs had a very weak delayed fluorescence signal. The enhancement in delayed fluorescence of Au NCs upon formation of assembly has been attributed to the crystallization-induced structural rigidity, which restricted the nonradiative transitions and enhanced the excited-state lifetime. The attainment of crystalline organization was substantiated by electron diffraction analysis. A possible structure was established based on experimental results and computational optimizations. Atomic force microscopy revealed the formation of multilayered two-dimensional nanosheets with thickness of 2.44 ± 0.48 nm.
Related Concept Videos
Polymer Classification: Crystallinity
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Dimensional Analysis
Conversion Factors and Dimensional Analysis
The unit...
Receptor-mediated Endocytosis
Body Temperature
The average body temperature is approximately 37°C (98.6°F) and typically ranges from 36.1–37.2°C...
Body Temperature

