A smart chitosan nonwoven fabric coated with coumarin-based fluorophore for selective detection and efficient adsorption of mercury (II) in water

Abstract

Mercury ion (Hg2+) has been considered as a hazardous heavy metal pollution in water, thus the development of a material for the sensitive detection and efficient adsorption of Hg2+ ions is significant. Herein, a novel coumarin-dithioacetal fluorophore named CA-S was synthesized, and then successfully coated on the chitosan nonwoven fabric. This functionalized fabric exhibited sensitive sensing and efficient adsorption toward Hg2+ ions. The fluorescence response mechanism of the functionalized fiber toward Hg2+ ions was confirmed by experiment and calculation. The detection limit of the functionalized fabric toward Hg2+ ions was 1.26 × 10−7 M. Moreover, this fabric showed favor adsorption capacity (over 1000 mg/g) and adsorption efficiency (within 10 min) toward Hg2+ ions. Meanwhile, this fabric was able to remove almost 99 % Hg2+ ions in real industrial water samples that satisfied the wastewater discharge standard.