Photocatalytic activity of the binary composite CeO<inf>2</inf>/SiO<inf>2</inf> for degradation of dye

• Main Authors: Phanichphant S., Nakaruk A., Channei D.
• Format: Journal
• Published: 2017
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84976376844&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/41289
• Institution: Chiang Mai University

© 2016 Elsevier B.V. In this study, CeO 2 photocatalyst was modified by composite with SiO 2 to increase efficiency and improve photocatalytic activity. The as-prepared SiO 2 particles have been incorporated into the precursor mixture of CeO 2 by homogeneous precipitation and subsequent calcination process. The phase compositions of CeO 2 before and after compositing with SiO 2 were identified by X-ray diffraction (XRD). The morphology and particle size of CeO 2 /SiO 2 composite was analyzed by high resolution transmission electron microscopy (HRTEM) and field emission scanning electron microscopy (FESEM). The results showed SiO 2 spheres with the particle size approximately 100–120 nm, and a uniform layer of CeO 2 nanoparticles with a diameter of about 5–7 nm that were fully composite to the surfaces of SiO 2 . The X-ray photoelectron spectroscopy (XPS) technique was carried out in order to characterize the change in valence state and composite characteristic by shifted peaks of binding energies. The photocatalytic activity was studied through the degradation of Rhodamine B in aqueous solution under visible light exposure. The highest photocatalytic efficiency of CeO 2 /SiO 2 composite was also obtained. To explain the high photocatalytic efficiency of CeO 2 /SiO 2 composite, the proposed mechanism involves the high surface properties of the CeO 2 /SiO 2 composite, as measured by Brunauer-Emmett-Teller (BET) method.