Interparticle Charge-Transport-Enhanced Electrochemiluminescence of Quantum-Dot Aerogels

Angew Chem Int Ed Engl. 2023 Jan 9;62(2):e202214487. doi: 10.1002/anie.202214487. Epub 2022 Dec 2.

Abstract

Electrochemiluminescence (ECL) represents a widely explored technique to generate light, in which the emission intensity relies critically on the charge-transfer reactions between electrogenerated radicals. Two types of charge-transfer mechanisms have been postulated for ECL generation, but the manipulation and effective probing of these routes remain a fundamental challenge. Here, we demonstrate the design of quantum dot (QD) aerogels as novel ECL luminophores via a versatile water-induced gelation strategy. The strong electronic coupling between adjacent QDs enables efficient charge transport within the aerogel network, leading to the generation of highly efficient ECL based on the selectively improved interparticle charge-transfer route. This mechanism is further verified by designing CdSe-CdTe mixed QD aerogels, where the two mechanistic routes are clearly decoupled for ECL generation. We anticipate our work will advance the fundamental understanding of ECL and prove useful for designing next-generation QD-based devices.

Keywords: Charge Transfer; Electrochemiluminescence; Electrochemistry; Quantum Dots; Sol-Gel Processes.