Rational design of a colorimetric and fluorescence turn-on chemosensor with benzothiazolium moiety for cyanide detection in aqueous solution

Abstract A novel colorimetric and fluorescence turn-on chemosensor TBB with benzothiazolium moiety has been explored, which exhibited the high selectivity for cyanide ion (CN − ) in THF–H 2 O (2:8, v /v) mixture. The aqueous solution of sensor TBB was scarcely emissive. In the presence of CN − ion, the nucleophilic addition of CN − with the benzothiazolium C N bond of TBB produced the new species TBB–CN , consequently resulting in the intense orange–red emission by aggregation-induced emission (AIE) effect. Meanwhile, the color of solution was changed from orange-yellow to light yellow. The sensing mechanism was verified by Mass spectrometry, NMR analysis and DFT calculations.