A highly sensitive “ON–OFF” optical sensor for the selective detection of cyanide ions in 100% aqueous solutions based on hydrogen bonding and water assisted aggregation induced emission

Abstract

Nanoparticles N,N′-(pyridine-2,6-diyl)bis(2-(2,4-dichlorophenoxy)acetamide) (1) exhibited an “on–off” emission response toward cyanide (CN⁻) ions in 100% aqueous solutions based on AIE features. AIEgen 1 is an easy-to-use probe that exhibits rapid response (5 s), extremely high sensitivity (limit of detection = 8.2 nM) and excellent selectivity. The sensing performance of CN⁻ through a test kit and bitter seed solutions was good. The experimental results show that compound 1 is planar and can self-assemble into a supramolecular system and show blue emission. Then, CN⁻ destroys both hydrogen bonds and the aggregates of 1 and quenches the emission. This process is reversible upon the addition of HCl solution.