scholarly journals Photocatalytic Degradation of Methylene Blue under UV Light Irradiation on Prepared CarbonaceousTiO2

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Zatil Amali Che Ramli ◽  
Nilofar Asim ◽  
Wan N. R. W. Isahak ◽  
Zeynab Emdadi ◽  
Norasikin Ahmad-Ludin ◽  
...  

This study involves the investigation of altering the photocatalytic activity of TiO2using composite materials. Three different forms of modified TiO2, namely, TiO2/activated carbon (AC), TiO2/carbon (C), and TiO2/PANi, were compared. The TiO2/carbon composite was obtained by pyrolysis of TiO2/PANi prepared by in situ polymerization method, while the TiO2/activated carbon (TiO2/AC) was obtained after treating TiO2/carbon with 1.0 M KOH solution, followed by calcination at a temperature of 450°C. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TG-DTA), Brunauer-Emmet-Teller (BET), and UV-Vis spectroscopy were used to characterize and evaluate the prepared samples. The specific surface area was determined to be in the following order: TiO2/AC > TiO2/C > TiO2/PANi > TiO2(179 > 134 > 54 > 9 m2 g−1). The evaluation of photocatalytic performance for the degradation of methylene blue under UV light irradiation was also of the same order, with 98 > 84.7 > 69% conversion rate, which is likely to be attributed to the porosity and synergistic effect in the prepared samples.

Water ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1622
Author(s):  
Xiao-Pin Guo ◽  
Peng Zang ◽  
Yong-Mei Li ◽  
Dong-Su Bi

2-methylisoborneol (2-MIB) is a common taste and odor compound caused by off-flavor secondary metabolites, which represents one of the greatest challenges for drinking water utilities worldwide. A TiO2-coated activated carbon (TiO2/PAC) has been synthesized using the sol-gel method. A new TiO2/PAC photocatalyst has been successfully employed in photodegradation of 2-MIB under UV light irradiation. In addition, the combined results of XRD, SEM-EDX, FTIR and UV-Vis suggested that the nano-TiO2 had been successfully loaded on the surface of PAC. Experimental results of 2-MIB removal indicated that the adsorption capacities of PAC for 2-MIB were higher than that of TiO2/PAC. However, in the natural organic matter (NOM) bearing water, the removal efficiency of 2-MIB by TiO2/PAC and PAC were 97.8% and 65.4%, respectively, under UV light irradiation. Moreover, it was shown that the presence of NOMs had a distinct effect on the removal of MIB by TiO2/PAC and PAC. In addition, a simplified equivalent background compound (SEBC) model could not only be used to describe the competitive adsorption of MIB and NOM, but also represent the photocatalytic process. In comparison to other related studies, there are a few novel composite photocatalysts that could efficiently and rapidly remove MIB by the combination of adsorption and photocatalysis.


Jurnal Kimia ◽  
2016 ◽  
Author(s):  
Ni Putu Diantariani ◽  
Iryanti Eka Suprihatin ◽  
Ida Ayu Gede Widihati

Research on  photodegradation of textile dyes  of methylene blue (MB) and congo red (CR) using ZnO-Activated Carbon composite and ultraviolet (UV) light has been done. This research included synthesis zinc oxide (ZnO), synthesis ZnO-Activated Carbon, and the application of composite to degrade textile dyes of MB and CR. In this research studied the effect of pH, concentration and time of UV radiation  towards photodegradation percentages  of dyes. Then it determined the rate and the effectivity of photodegradation of MB and CR dyes using ZnO-Activated Carbon composite. The result showed that  photodegradation of MB reach optimal condition at pH 11 with radiation time 4 hour, whereas CR is at pH 5 with the same radiation time. The more initial concentration of MB and CR applicated, the lower of photodegradation percentages. Constanta of photodegradation rate of MB and CR dyes using ZnO-Activated Carbon composite are 0.8316 and 1.4938 hour-1 respectively. ZnO-Activated Carbon composite as a photocatalyst can degrade effectively MB and CR dyes with photodegradation percentages of 99.40±0.23 % and 99.61±0.24% respectively.


2020 ◽  
Vol 979 ◽  
pp. 175-179
Author(s):  
M. Nagalakshmi ◽  
N. Anusuya ◽  
S. Karuppuchamy

Titanium dioxide (TiO2) nanoparticles have been successfully prepared by biological method and the resulting material was characterized by XRD, FTIR, SEM, EDAX and UV-Vis spectroscopy. The synthesized TiO2 materials successfully degraded the methylene blue dye (MB) under UV light irradiation.


2021 ◽  
Author(s):  
Judith Chebwogen ◽  
Christopher Mkirema Maghanga

Population growth and urbanization have led to water scarcity and pollution, which is a health hazard not only to humans but also to the ecosystem in general. This has necessitated coming up with ways of treating water before consumption. Photocatalysis has proved to be one of the most promising cheap techniques that involve chemical utilization of solar energy. TiO2 widely used in photocatalysis absorbs a narrow range of the solar spectrum compared to ZnO. In this regard, this study aimed at preparing and optimizing cobalt-pigmented ZnO, which is applicable in photocatalytic water treatment. The objectives in this study were to fabricate zinc oxide (ZnO) thin films by anodization, pigment the fabricated films with varying cobalt concentrations, characterize the fabricated films optically, and investigate the cobalt-pigmented ZnO’s performance in the methylene blue degradation under UV light irradiation. Mirror-polished zinc plates were sonicated in ethanol and rinsed. Anodization was done at room temperature in 0.5 M oxalic acid at a constant voltage of 10 V for 60 min, and cobalt electrodeposited in the films. Post-deposition treatment was done at 250°C. Optical properties of the films were studied using a UV-VIS- NIR spectrophotometer in the solar range of 300–2500 nm. The photocatalytic activity of the fabricated films was studied in methylene blue solution degradation in the presence of UV light irradiation for 5 h. Cobalt pigmenting was observed to reduce reflectance and optical band gap from 3.34 to 3.10 eV indicating good photocatalytic properties. In this study, ZnO film pigmented with cobalt for 20 s was found to be the most photocatalytic with a rate constant of 0.0317 h−1 and hence had the optimum cobalt concentration for photocatalytic water treatment. This can be applied in small-scale water purification.


Catalysts ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 499 ◽  
Author(s):  
Hafize Koysuren

In this study, polymer composites based on polyvinyl borate (PVB) with titanium dioxide (TiO2) nanoparticles were prepared through the condensation reaction of polyvinyl alcohol and boric acid in the presence of TiO2 nanoparticles. The solid-phase photocatalytic degradation of the polymer composites under UV light irradiation was investigated and compared with that of the pure PVB with the aid of weight loss measurements. The introduction of the photocatalyst nanoparticles in PVB enhanced the solid-phase photocatalytic degradation of the polymer matrix under UV light irradiation. The structural and morphological properties of PVB/TiO2 composites were analyzed by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and UV-Vis spectroscopy, respectively. FTIR analysis revealed that PVB synthesis was successfully carried out in the presence of the photocatalyst nanoparticles. According to the morphological analyses, TiO2 nanoparticles were well dispersed in the PVB matrix.


2012 ◽  
Vol 512-515 ◽  
pp. 1677-1681
Author(s):  
Feng Zhou ◽  
Ying Qing Fu ◽  
Xin Wan

A facile route was demonstrated to obtain an efficient graphene-hybridized TiO2 photocatalyst. The photodegradation results of Methylene Blue over graphene hybridized with TiO2 showed that the photocatalytic activity could be significantly enhanced under UV light irradiation. The structure between TiO2 and graphene as well as its effect on the photocatalytic activity were systematically investigated. The mechanism of the enhanced photocatalytic activity is based to the high migration efficiency and the inhibition of recombination of photoinduced electron-hole pairs. The graphene hydridization is proven to be a promising approach to develop highly efficient and stable photocatalysts under UV light irradiation.


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