Enhanced Photocatalytic Degradation of Methyl Orange Dye under the Daylight Irradiation over CN-TiO2 Modified with OMS-2

Abstract

In this study, CN-TiO2 was modified with cryptomelane octahedral molecular sieves (OMS-2) by the sol-gel method based on the self-assembly technique to enhance its photocatalytic activity under the daylight irradiation. The synthesized samples were characterized by X-ray diffraction (XRD), UV-vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and porosimeter analysis. The results showed that the addition of OMS-2 in the sol lead to higher Brunauer-Emmett-Teller (BET) surface area, pore volume, porosity of particle after heat treatment and the specific surface area, porosity, crystallite size and pore size distribution could be controlled by adjusting the calcination temperature. Compared to the CN-TiO2-400 sample, CN-TiO2/OMS-2-400 exhibited greater red shift in absorption edge of samples in visible region due to the OMS-2 coated. The enhancement of photocatalytic activity of CN-TiO2/OMS-2 composite photocatalyst was subsequently evaluated for the degradation of the methyl orange dye under the daylight irradiation in water. The results showed that the methyl orange dye degradation rate reach to 37.8% for the CN-TiO2/OMS-2-400 sample under the daylight irradiation for 5 h, which was higher than that of reference sample. The enhancement in daylight photocatalytic activities of the CN-TiO2/OMS samples could be attributed to the synergistic effects of OMS-2 coated, larger surface area and red shift in adsorption edge of the prepared sample.

Study of the Structure, Electronic and Optical Properties of BiOI/Rutile-TiO2 Heterojunction by the First-Principle Calculation

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Photocatalytic Degradation of 4-Nitrophenol by C, N-TiO2: Degradation Efficiency vs. Embryonic Toxicity of the Resulting Compounds

“…Carbon doping can make TiO 2 sensitive to visible light with improved adsorption capacity for organic pollutant molecules (Park et al, 2006 ; Dong et al, 2011 ). Moreover, the simultaneous doping of two types of atoms into TiO 2 , such as N–F (Li et al, 2005a , b ; Giannakas et al, 2013 ; Wang et al, 2014 ), N–S (Yu et al, 2006 ), and C–N (Wang and Lim, 2010 , 2011 ; Hassan et al, 2014 ; Trevisan et al, 2014 ), has recently attracted considerable interests, for the possible integrated or synergistic effects by the co-doped elements.…”

Parameters affecting the photocatalytic degradation of dyes using TiO2: a review

“…Heterogeneous catalysis has been successfully employed for the degradation of various families of hazardous materials. Titanium dioxide (TiO 2 ), due to its non-toxic, inexpensive, and high reactive nature, has been extensively investigated as a heterogeneous photocatalyst for the remediation of contaminated environment (Hassan et al 2014;Harbi et al 2015;Kim et al 2005). The advantage of TiO 2 as photocatalyst is that organic pollutants are usually completely mineralized to non-toxic substances such as CO 2 , HCl and water and thus the reactions do not suffer the drawbacks of photolysis reactions in terms of the production of intermediate products.…”