Sub-3 nm Aluminum Nanocrystals Exhibiting Cluster-Like Optical Properties.

Metal nanoclusters with distinct photophysical and photochemical properties have drawn intense research interests for their applications in optoelectronics, catalysis, and biomedicine. Herein, strong evidence is provided that light metal is capable of generating comparable optical responses of noble metal nanoclusters, but at much shorter wavelength. Air-stable, size-uniform, sub-3 nm aluminum nanocrystals are prepared with simple solution based synthetic procedures, with photoluminescence located in the ultraviolet range and short exciton lifetime. Partial modulation of the photoluminescence is achieved, indicating the key role of surface oxides. This work is envisioned to inspire new frontiers of nanocluster research with light metals.