A novel colorimetric and fluorescent sensor for cyanide anions detection based on triphenylamine and benzothiadiazole.

A chemical sensor containing triphenylamine and benzothiadiazole for cyanide anions detection was designed and synthesized, whose structural feature is a donor-acceptor-donor (D-A-D) molecular configuration, which is substituted with a dicyanovinyl group served as a sensing unit. The nucleophilic addition of cyanide ion to the dicyanovinyl moiety was activated in the principle of Michael addition, which broken the electron-withdrawing interaction of dicyanovinyl moiety. The obstruction in the intramolecular charge transfer (ICT) induced remarkable changes in the absorption and emission spectra. The sensor exhibited splendid selectivity and anti -interference performance towards CN − over other anions (F − , Cl − , Br − , I − , NO 2 − , NO 3 − , HCO 3 − , H 2 PO 4 − , HS − , HSO 3 − , NCO − , SCN − , SO 3 2− , SO 4 2− , HPO 4 2− , CO 3 2− ). The mechanism was investigated by absorption and emission spectra together with 1 H NMR titration. [ABSTRACT FROM AUTHOR]