Luminescent macrocyclic Sm(III) complex probe for turn-off fluorescent and colorimetric water detection in organic solvents and liquid fuels

Abstract

The rapid and sensitive detection of water has attracted wide interests in the chemical and energy industry for its harmful influences, which encourage researchers to explore kinds of materials for sensing water. Herein, we report the sensing performance of a Schiff-base macrocyclic Sm(III) complex Sm-2g as the turn-off fluorescent and colorimetric probe for water detection in organic solvents (DMF, methanol and acetone) and liquid fuels (bioethanol and avgas). It is especially encouraging that the probe Sm-2g exhibits a rapid and sensitive response for water, and it could be easily distinguished by the distinct fluorescence quenching and absorption shift. Electrospray ionization mass spectra prove that this efficient detection is achieved based on the transformation from complex Sm-2g to corresponding dialdehyde precursor, originating from the imine bond cleavage after the addition of water. Furthermore, the Sm-2g impregnated paper strip also provides a convenient way to detect water by its rapid and distinguishable fluorescent color changes in organic media. Therefore, the luminescent Sm(III) complex Sm-2g shows promise as a valuable candidate for the detection of water.