Efficient Near‐Infrared Electrochemiluminescence from Au18 Nanoclusters

• Published in: Chemistry : a European journal Vol. 27; no. 60; pp. 14821 - 14825
• Main Authors: Hesari, Mahdi, Ding, Zhifeng
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 25.10.2021
• Subjects: Chemistry; Efficiency; Electrochemiluminescence; gold nanoclusters; nano-electrochemistry; Nanoclusters; Near infrared radiation; near-IR electrochemiluminescence; Oxidation; Photoluminescence; Photons; Spectroscopy; Spooling; spooling photoluminescence spectroscopy
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202102926

Bright, near‐infrared electrochemiluminescence (NIR–ECL) of Au18 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, Au180*, Au181+* and Au182+*, with a considerably high ECL efficiency of 5.5 relative to that of the gold standard Ru(bpy)32+/TPrA (with 5–6 % reported ECL efficiency). The unprecedentedly high efficiency is due to the overlapped oxidation potentials of Au180 and tri‐n‐propylamine as co‐reactant, the exposed facets of Au180 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. Highest ECL quantum efficiency: Near‐infrared electrochemiluminescence (NIR–ECL) of Au18(SC6H11)140 nanoclusters was explicitly explored; it reveals the highest ever quantum efficiency of 5.5 relative to that of standard Ru(bpy)32+ for the Au nanocluster family. ECL peak wavelengths of 832 and 848 nm were assigned unambiguously to the emission from Au180*, Au181+* and Au182+* in terms of spooling ECL and photoluminescence spectroscopy.