Ingenious dual-emitting Ru@UiO-66-NH2 composite as ratiometric fluorescence sensor for detection of mercury in aqueous

The increasing deterioration of ecosystem derived from heavy metals residues brings about the environmental and food contamination , which presses the exploration of facile platform for monitoring heavy metals. Herein, a ratiometric fluorescence sensor was designed for Hg 2+ detection based on the compound of UiO-66-NH 2 and Ru(bpy) 3 2+ (Ru@UiO-66-NH 2 ) which was synthesized by situ encapsulation. The innovative composite displayed two emission peaks at 437 and 604 nm, and the addition of Hg 2+ could only quench the blue fluorescence due to static quenching and photo-induced electron transfer mechanism, providing an internal standard to promote the precision. Under optimal conditions, the ratiometric Ru@UiO-66-NH 2 probe revealed outstanding anti-interference capability and performed with a great limit of detection (LOD) of 0.053 μM for Hg 2+ , which was 2-fold lower than that of single-color UiO-66-NH 2 . By merit of Ru@UiO-66-NH 2 , test hydrogels were fabricated to provide a tactics for visual, rapid and on-site detection of Hg 2+ . Additionally, the dual-emitting sensing platform presented satisfactory recoveries and reliabilities in lake water, tap water , and drink water, demonstrating the application potential of this proposed ratiometric fluorescence sensor for monitoring Hg 2+ .