Cyanide Recognition and Phase‐Selective Removal of Toxic Cationic Dyes from Water Using a New Naphthalimide‐coupled Poly (aryl ether) Gelator

Abstract

In the work, a new naphthalimide‐linked poly(aryl ether) gelator 1 has been designed and synthesized. It forms gels in various organic and aquous organic solvents and exhibits aggregation‐induced enhancement of emission (AIEE) through the tuning of gelling solvent. Gels are of good viscoelastic nature showing higher magnitude of G′ over G′′ and exhibit fibrous morphology. Among the different gels, DMSO : H2O (7 : 3, v/v) gel with considerable rigidity selectively detects CN− over the other anions via deprotonation mechanism and involves a gel‐to‐sol colour change. In addition, n‐butanol : H2O (9 : 2, v/v) gel shows the same property. The water in gelling medium has the pertinent role in anion recognition selectivity, aggregation and AIEE. While in solution F− interferes in CN− sensing, there is no interference of it in the gel state. Besides sensing, n‐butanol gel of 1 removes the toxic cationic dyes from wastewater to the extent of 98–99 % in phase selective manner.