Design of a Solvation-Based Chemiluminescence Sensing Platform for Water in Organic Solvents

Chemiluminescence (CL) sensing has emerged as a promising paradigm due to its advantages of high sensitivity, simple operation, low cost, and low background. However, the availability of effective chemiluminophores remains limited, which substantially impedes their practical applications. Herein, we utilized the donor 4-[2-(4-formylphenyl)ethynyl]benzaldehyde (EDA) and the photosensitive acceptor 2,4,6-trimethyl-1,3,5-triazine (TMT) to synthesize a D-A COF (EDA-TMT) with excellent charge transfer, charge carrier separation efficiencies, and fluorescence properties. For the first time, it was found that the DMSO suspension of EDA-TMT can be induced to produce distinct CL by water after being exposed to natural light for a period. The CL mechanism was unveiled in-depth by various characterization techniques and analyses. The results indicated that solvation and the annihilation/recombination of EDA•+-TMT and EDA-TMT•- are core to the CL. Based on this, a solvation-based CL sensing platform for water in organic solvents with an exceptionally wide linear range, impressive sensitivity, and reproducibility has been successfully constructed. This study builds a bridge between photocatalysis and CL, which opens up a novel pathway to obtain effective chemiluminophores and design a CL sensing platform for practical application.