Interrogating Near-Infrared Electrogenerated Chemiluminescence of Au_(25)(SC_2H_4Ph)_(18)~+ Clusters

摘要

The electrochemistry, near-infrared photo-luminescence (NIR-PL) spectroscopy, and electrogenerated chemiluminescence (ECL) of Au_(25)(SC_2H_4Ph)_(18)~+-C_6F_5CO_2~-(Au_(25)~+) clusters were investigated. For the first time, NIR-ECL emission was observed in both annihilation and coreactant paths. Our newly developed spooling spectroscopy was employed during the ECL evolution and devolution processes along with explicit NIR-PL spectroscopy to elucidate light generation mechanisms. It was discovered that the electronic relaxation of the Au_(25)~-excited state to the ground state plays a key role in giving off ECL at 893 nm, while intermediate, strong, and weak NIR-PL emissions at 719/820, 857, and 1080 nm can be attributed to the excited states higher than the HOMO-LUMO gap, across the HOMO-LUMO gap, and of semirings, respectively.