Efficient Near-Infrared Electrochemiluminescence from Au18 Nanoclusters

Bright, near-infrared electrochemiluminescence (NIR-ECL) of Au-18 nanoclusters is reported herein. Spooling ECL and photoluminescence spectroscopy were used to track and link NIR emissions at 832 and 848 nm to three emissive species, Au-18(0)*, Au-18(1+)* and Au-18(2+)*, with a considerably high ECL efficiency of 5.5 relative to that of the gold standard Ru(bpy)(3)(2+)/TPrA (with 5-6 % reported ECL efficiency). The unprecedentedly high efficiency is due to the overlapped oxidation potentials of Au-18(0) and tri-n-propylamine as co-reactant, the exposed facets of Au-18(0) gold core, and electrocatalytic loops. These discoveries will add a new member to the efficient NIR-ECL gold nanoclusters family and bring more potential applications.

Automated summary

This study reports the bright near-infrared electrochemiluminescence (NIR-ECL) of Au-18 nanoclusters with a high ECL efficiency of 5.5. The overlapping oxidation potentials of Au-18(0) and co-reactant tri-n-propylamine, exposed facets of Au-18(0) gold core, and electrocatalytic loops contribute to this unprecedentedly high efficiency, potentially expanding the applications of gold nanoclusters in efficient NIR-ECL.