Facile synthesis of multicolor organic-inorganic hybrid pigments based on layered double hydroxides

C.I. Acid Yellow 25 and C.I. Acid Blue 25 have been co-intercalated into the interlayer galleries of ZnAl layered double hydroxides by co-precipitation method to produce multicolor organic-inorganic hybrid pigments. The obtained pigments are characterized by X-ray diffraction, scanning electron microscopy, fourier transform infrared spectroscopy, thermogravimetric-differential thermogravimetric-differential thermal analysis, ultraviolet visible spectroscopy, chemical composition and CIE 1976 L*a*b* color scales. The results suggest that there exist host-guest interactions between host sheets and guest dye anions and guest-guest interactions between the dye anions. The intercalation into the interlayer region of layered double hydroxides significantly improves the thermostability of the two dyes. The color of the organic-inorganic hybrid pigments can be easily tuned from orange yellow to yellow green, yellowish green, green, bluish green and blue by adjusting the molar ratio of dye anions in the interlayer room of layered double hydroxides. (C) 2013 Elsevier Ltd. All rights reserved.