Novel kaolin/polysiloxane based organic-inorganic hybrid materials: Sol-gel synthesis, characterization and photocatalytic properties

Publication date: April 2018 Source:Journal of Solid State Chemistry, Volume 260 Author(s): Glaydson Simões dos Reis, Eder Cláudio Lima, Carlos Hoffmann Sampaio, Fabiano Severo Rodembusch, Carlos Otávio Petter, Bogdan Grigore Cazacliu, Guillherme Luiz Dotto, Gelsa Edith Navarro Hidalgo New hybrid materials using kaolin and the organosilicas methyl-polysiloxane (MK), methyl-phenyl-polysiloxane (H44), tetraethyl-ortho-silicate (TEOS) and 3-amino-propyl-triethoxysilane (APTES) were obtained by sol-gel process. These materials presented specific surfaces areas (SBET) in the range of 20–530 m2 g−1. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed remarkable differences between the kaolin and hybrid structures. Thermogravimetric analysis (TGA) revealed that the hybrid materials presented higher thermal stability when compared with their precursors. The electronic properties of the materials were also studied by Ultraviolet-Visible Diffuse Reflectance Absorption (DRUV) and Diffuse Reflectance spectroscopy (DR), where a new absorption band was observed located around 400–660 nm. In addition, these materials exhibit a decrease in DR from 30% to 70% in the blue-cyan green region and are significantly more transparent in the UV region than the kaolin, which could be useful for photocatalysis applications. These results show that the electronic structure of the final material was changed, indicating a significant interaction betw...

Source: Journal of Solid State Chemistry - February 4, 2018 Category: Chemistry Source Type: research