Aggregation induced emission-excited state intramolecular proton transfer based off-on fluorescent sensor for Al3+ ions in liquid and solid state

Benzophenone azine based schiff base exhibiting AIE and ESIPT phenomenon has been synthesised and studied the photophysical behaviour towards detection of AP' ions. The results showed that compound 2 exhibit feeble excited state intramolecular proton transfer emission in CH3CN and undergo aggregation induced emission in >70% H2O-CH3 CN. The compound 2 shows significant hydrodynamic diameter change from 20 nm to 200 nm upon increasing the H2O volume ratio in CH3 CN. Compound 2 shows colorimetric and off-on emission response for Al3+, with detection limit of 2.7 x 10(-7)M in CH3OH. The association of compound 2 to Al3+ also causes restriction in intramolecular motion induced emission. The hydrodynamic diameter of compound 2 increases from 335 nm to 625 nm in the presence of Al3+ ion in CH3OH. (C) 2018 Elsevier B.V. All rights reserved.