A highly stable and efficient benzothiadiazole-based fluorescence sensor for salicylaldehyde in aqueous solution

A Cd II -based coordination polymer with the formula [Cd(BIBT)(3,4-TDC)] n ( JXUST-27 , BIBT = 4,7-bi(1 H -imidazol-1-yl)benzo-[2,1,3]thiadiazole and 3,4-H 2 TDC = thiophene-3,4-dicarboxylic acid) was synthesized under solvothermal conditions. Single-crystal structural determination reveals that JXUST-27 adopts a two-dimensional structure with sql topology. JXUST-27 can keep stable up to 317 °C and in common solvents. In particular, JXUST-27 exhibits excellent stability when the samples are immersed in aqueous solutions with pH values of 2-13 or in boiling water for 24 hours. Furthermore, JXUST-27 could selectively detect salicylaldehyde (SA) through turn-off effect with a detection limit of 0.087 μM. More importantly, JXUST-27 represents the first Cd II coordination polymer based fluorescence sensor toward SA in aqueous solution. In addition, the portable fluorescent film and light-emitting diode lamp based on JXUST-27 were further developed for the detection of SA. A water-stable and pH-stable CP-based fluorescence probe ( JXUST-27 ) can sense SA via fluorescence quenching with high selectivity and sensitivity. Remarkably, the fluorescence film and LED lamp have been further developed to detect SA.