Self-Quenching-Resistant Carbon Dot with Tunable Solid-State Fluorescence

Abstract

Aggregation-induced emission quenching (ACQ) of carbon dots (CDs) is the main obstacle to their solid-state application. Herein, self-quenching-resistant CDs with tunable solid-state fluorescence (SSF) were obtained via the electrochemical method in separate electrodes simultaneously, where redox reactions from the cathode and anode are employed to construct a differentiated strategy for surface-state modulation with modifying molecules. The key feature of this approach is the tunable emission from morphological changes of o-phenylenediamine within the anode and cathode, considerable steric hindrance from long chains and guanidino groups on CDs introduced by D-arginine. The guanidino groups, in particular, enhanced spatial steric hindrance in situ and suppressed ACQ through a hydrogen-bonding network. Furthermore, such SSF CDs with emission at 550 nm (Y-CD) and a main emission at 646 nm (R-CD) exhibit great potential for applications of light emitting diodes (LEDs) and multi mode anti-counterfeiting.