Příprava a vlastnosti nanočástic oxidů přechodných kovů na kaolinitové matrici

Abstract

Preparation of nanocomposites kaolinite/TiO2, using hydrolysis of titanyl sulfate in the presence of kaolin was addressed. Copper-doping has been carried out for selected samples of nanocomposites. The preparation procedure has been optimized in order to achieve the maximum photoactivity by minimum energy and material saving. A variable (kaolinite)/(titanyl sulfate) ratio has been used in order to achieve the desired TiO2 content in prepared nanocomposites. Calcination of the composites at 600 °C led to the transformation of the kaolinite to metakaolinite and to origination of metakaolinite/TiO2 composites. The prepared samples were investigated using X-ray fluorescence spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy and diffuse reflectance spectroscopy in the UV-VIS region. Structural ordering of TiO2 on the kaolinite particle surface was modeled using empirical force field atomistic simulations in the „Materials Studio“ modeling environment. Photodegradation activity of the composites prepared was evaluated by the discoloration of Acid Orange 7 aqueous solution.