TiO2/DMS-1 disordered mesoporous silica system: Structural characteristics and methylene blue photodegradation activity

• DOI: 10.1016/j.micromeso.2012.11.027
• Publication Date: 2012-11-29T02:46:33Z
• Authors: Y.J. Acosta-Silva; R. Nava; V. Hernández-Morales; S.A. Macías-Sánchez; B. Pawelec
• Keywords: Photodegradation; Methylene blue; Diffuse reflection

Financial support by PROMEP (Project UAQ-PTC-190) is gratefully acknowledged. This study is partially supported by The Spanish Ministry of Science and Innovation (ENE2007-67533-C02-01 project) and The Community of Madrid (S2009ENE-1743 project).<br/>Disordered mesoporous silica (DMS-1) material was synthetized using nonionic surfactant as liquid template and tetraethyl orthosilicate (TEOS) as silica precursor. The x%TiO2/DMS-1 systems (x = 7–35 wt.% of TiO2) were synthetized by the post-synthesis grafting of the calcined DMS-1 substrate. Characterization by several techniques (N2 adsorption–desorption isotherms, X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS), micro-Raman spectroscopy and X-ray photoelectron spectroscopy (XPS)) indicates that the x%TiO2/DMS-1 systems consist of TiO2 anatase nanoparticles located on the external substrate surface. The photocatalytic behavior of these samples was evaluated in the photodegradation of methylene blue (MB) dye carried out under ultraviolet light illumination at room temperature. An important enhancement in the photocatalytic activity of the x%TiO2/DMS-1 with respect to unsupported TiO2 (P-25) sample was observed. The MB photodegradation activity increased linearly with an increase of the TiO2 loading from 7 to 35 wt.%. The highest activity of the 35%TiO2/DMS-1 sample was explained as due to the enhancement of anatase surface exposure with respect to the other photocatalysts.<br/>Peer Reviewed<br/>