Deposition of colored inorganic coating layers on lamellar sericite surface and the pigmentary performances

The inorganic composite pigments, Fe2O3/sericite, Bi2O3/sericite, and CoAl2O4/sericite, were prepared by the homogeneous hydrolysis of metal salts, such as FeCl3, Bi(NO3)3, and Co(NO3)2/Al(NO3)3. The deposition of the inorganic coating layers on sericite surfaces was explored by X-ray diffraction, scanning electron microscopy, Fourier transform infrared, and X-ray photoelectron spectroscopy. The inorganic coating layers were uniformly and tightly anchored at sericite surfaces via chemical bonding at the interface between the coating layer and the sericite substrate. The pigmentary performances of the inorganic composite pigments were analyzed by CIE, indicating that red, yellow, and blue colored pigments were achieved by coating Fe2O3, Bi2O3, and CoAl2O4 on sericite surfaces, respectively. The pigmentary performances of the inorganic composite pigments were significantly affected by the morphology and thickness of inorganic coating layers.

Graphical abstractThe inorganic composite pigments, Fe2O3-, Bi2O3-, and CoAl2O4-coated sericite, were prepared. The inorganic coating layers were uniformly and tightly anchored at sericite surfaces. The red, yellow, and blue colored pigments were achieved. The pigmentary performances of the inorganic composite pigments were significantly affected by the morphology and thickness of the inorganic coating layers.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Inorganic composite pigments, Fe2O3-, Bi2O3-, and CoAl2O4-coated sericite, were prepared by the chemical deposition method. ► The colored inorganic coating layers were anchored at the sericite surfaces via chemical bonds. ► The red, yellow, and blue colored inorganic composite pigments were achieved by varying the type of the coating layers. ► The pigmentary properties of the inorganic composite pigments were affected by the morphology and loading of the coatings.