Sunlight-Induced Photocatalytic Degradation of Organic Pollutants by Carbon-Modified Nanotitania with Vegetable Oil as Precursor

Abstract

An attempt has been made in this study to prepare a nanosized titanium dioxide catalyst by an ultrasonication assisted sol−gel process at low temperature. The as-synthesized titania was modified with carbon from coconut oil as a carbon precursor in two different proportions and then subjected to thermal and microwave treatment. The characterization of the pure and carbon modified titania catalysts was accomplished by XRD, SEM, HR-SEM/EDX, UV−vis absorption spectroscopy, and BET surface area analysis. The average size of the carbon modified TiO2 catalysts was found to be in the range of 90 nm. The solar photocatalytic activity of the catalysts was monitored by the degradation of a cationic dye, methylene blue, and an anionic dye, methyl orange. The effect of pH on the degradation of the dyes was also investigated. The study revealed that the degradation of the cationic dye was highly pronounced in the alkaline pH, whereas, the degradation of the anionic dye was effective in acidic pH. A solar photochemical study was also conducted with 2,4-dichlorophenol to ensure the degradation of visible light nonabsorbing organic compounds. The study revealed that carbon-modified catalysts with about 8.0 wt % of carbon was found to have the highest solar phoactivity, when compared to the pure titania and the carbon modified titania with 42% of carbon.

Hydrothermal Synthesis of Graphene/Bi2WO6 Composite with High Adsorptivity and Photoactivity for Azo Dyes

“…Among all kinds of modification methods, nonmetal doping has been regarded as one of most effective approaches to improve the visible‐light‐driven photocatalytic activity. Many groups have proved that carbon doping can greatly enhance the photocatalytic activity of metal oxide catalysts in the visible‐light region and broaden the absorption for solar spectrum . Many efforts have been taken on doping TiO 2 with carbon to achieve better band‐gap narrowing and visible‐light response.…”

Morphology-controlled electrodeposition of Cu2O microcrystalline particle films for application in photocatalysis under sunlight

“…Some photocatalysts, such as oxide-TiO 2 composites [1,2], Fe 2 O 3 [3], carbon modified TiO 2 [4], and some element-doped TiO 2 [5,6], have been employed and intensively studied in degradation of many organic pollutants. Cuprous oxide (Cu 2 O), an inexpensive and important p-type semiconductor with a direct band gap of around 2.17 eV, is another promising photocatalyst with low toxicity and good environmental acceptability.…”

Preparation, characterization and photocatalytic activity evaluation of micro- and mesoporous TiO2/spherical activated carbon

“…The SAC before TiO 2 immobilization is an amorphous phase. At a stabilization temperature of 300 8C, a broad peak at 2u = 25.28, 37.68, 48.28, 55.18, and 62.98 corresponds to the anatase [37][38][39][40]. Increasing the carbonization temperature up to 700 8C, the peak intensities of anatase increased and became sharp, indicating the formation of greater TiO 2 crystallites and enhancement of crystallization [40].…”