Imine linked chemosensors coupled with ZnO: fluorescent and chromogenic detection of Al3+

The surface of ZnO nanoparticles is decorated with dipodal receptors having imine linkages. The cation recognition properties of pure dipodal receptors and same receptors coated on ZnO have been compared. The dipodal receptors which were previously non-selective become highly selectivity for Al3+ after capping on the surface of ZnO nanoparticles. The ZnO nanoparticles were prepared by the sol–gel method and characterized through powder X-ray diffraction. Two spectroscopic techniques have been used to study the cation recognition behavior of receptors. The ZnO coated assemblies authenticate their use as sensitive sensors for Al3+ in a semi-aqueous medium by showing some remarkable changes in its profile.