Efficient photocatalytic activity with carbon-doped SiO sub(2) nanoparticles

• Published in: Nanoscale Vol. 5; no. 13; pp. 6167 - 6172
• Main Authors: Zhang, Dongen, Wu, Jinbo, Zhou, Bingpu, Hong, Yaying, Li, Shunbo, Wen, Weijia
• Format: Journal Article
• Language: English
• Published: 01.06.2013
• Subjects: Carbon; Nanomaterials; Nanostructure; Photocatalysis; Photocatalysts; Semiconductors; Silicon dioxide; X-rays
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/c3nr01314f

Photocatalysis provides a 'green' approach to completely eliminate various kinds of contaminants that are fatal for current environmental and energy issues. Semiconductors are one of the most frequently used photocatalysts as they can absorb light over a wide spectral range. However, it is also well known that naked SiO sub(2) is not an efficient photocatalyst due to its relatively large band gap, which could only absorb shortwave ultraviolet light. In this report, nanoscale particles of carbon-doped silicon dioxide (C-doped SiO sub(2)) for use in photocatalysis were successfully prepared by a facile one-pot thermal process using tetraethylorthosilicate (TEOS) as the source of both silicon and carbon. These particles were subsequently characterized by thermogravimetric analysis, X-ray diffraction, standard and high resolution transmission electron microscopy and X-ray photoelectron spectroscopy. The C-doped SiO sub(2) displayed outstanding photocatalytic properties, as evidenced by its catalysis of Rhodamine B degradation under near-UV irradiation. We propose that carbon doping of the SiO sub(2) lattice creates new energy states between the bottom of the conduction band and the top of the valence band, which narrows the band gap of the material. As a result, the C-doped SiO sub(2) nanoparticles exhibit excellent photocatalytic activities in a neutral environment. The novel synthesis reported herein for this material is both energy efficient and environmentally friendly and as such shows promise as a technique for low-cost, readily scalable industrial production.