A One‐Pot Synthesized Chemodosimetric Chemosensor for Highly Sensitive Cyanide Ion Detection in Aqueous Media and from Tobacco Smoke

Abstract A sustainable future world consistently attributes to the development of eco‐friendly methods and materials for detection and elimination of toxic substances from the environment. While addressing the issues, pyrazole carbonitrile derived Schiff base PYR−TZ has been designed and employed for colorimetric and turn on fluorometric cyanide ion sensing. PYR−TZ demonstrated high cyanide ion (CN − ) sensitivity with a 1 : 1 binding stoichiometry in aqueous solution. By preventing intramolecular charge transfer, the PYR−TZ sensor demonstrated excellent selectivity towards CN, which caused a color transition from colorless to yellow and impressive “turn‐on” fluorescence emission. The detection thresholds for CN − are 6.5 nm for absorbance spectra and 0.396 nm emission spectra, respectively. Under typical ecological and physiological settings (pH 1–12), the PYR−TZ sensor can function as an effective chemical sensor for detecting the CN − ions. Additionally, the sensor can find CN in tobacco commercial products like cigarettes and cigars. PYR−TZ is a great cyanide sensor probe that has a number of benefits, which includes simple synthesis, distinct color and emission change, a high degree of selectivity, lesser limit of detection, reversibility, and good anti‐interference ability to analyze solution and tobacco commercial things, together with fluorescence imaging. The theoretical optimized structure and electronic transitions were confirmed by DFT and TDDFT studies. On the basis of theoretical and experimental calculations (DFT), the mechanism of the metal ion complex is postulated.