Structural properties and photocatalytic activity of ceria nanoparticles on vermiculite matrix

Abstract

Clay mineral matrices and metal oxides are of current interest because of their high thermal stability, large surface area, and good catalytic and adsorption properties. Cerium oxide (ceria, CeO2) nanoparticles was obtained by interaction of vermiculite with (NH4)(2)Ce(NO3)(6). The mean crystallite size of CeO2 nanoparticles in the vermiculite was (8.5 +/- 0.5) nm. The HRTEM micrographs confirmed the crystallite size and revealed additionally the shape of crystallites. The intercalation of the cerium reaction products into vermiculite was proven by using X-ray diffraction and ICP-AES. The incorporation of ceria into vermiculite increased the surface area from 14 to 62 m(2) . g(-1) and the volume of micropores from 0.1213 to 0.3928 cm(3) . g(-1), and reduced the average pore diameter from 264 nm to 58.5 nm. Under UV irradiation, decomposition of N2O influenced by the sole CeO2 and 36 wt% CeO2 attached to the vermiculite was 57.7% and 53.3%, respectively, in comparison with the decomposition of 51.6% by commercial catalyst Evonik P25.