Palygorskite-based hybrid fluorescent pigment: Preparation, spectroscopic characterization and environmental stability

A new hybrid fluorescent pigment was prepared combining the adsorption of a fluorescent yellow X-10GFF (FY-10G, a coumarin derivative fluorescent dye) on palygorskite (PAL) with the silica encapsulation by the hydrolysis of tetraethoxysilane (TEOS) using acetic acid as catalyst. The photo-stability under UV irradiation and the resistance toward acid, alkali and ethanol of the SiO2@FY-10G/PAL hybrid fluorescent pigments were systematically discussed. The results show that the introduction of PAL not only significantly influences the absorption and fluorescence spectra of the FY-10G, but also enhances the thermal stability of FY-10G due to the supramolecular host/guest interactions. The encapsulation of the silica coating can effectively improve thermal- and photo-stability of FY-10G. Moreover, the fluorescent intensity and the resistance of the hybrid fluorescent pigments to acid and organic solvent enhance with the increase of TEOS concentration. (C) 2015 Elsevier Inc. All rights reserved.