Preparation Conditions and Properties of Porous SiO2-Doped TiO2 Photocatalyst

2011 ◽  
Vol 214 ◽  
pp. 40-44
Author(s):  
Hong Li ◽  
Qian Li ◽  
Wen Jie Zhang

A porous SiO2-doped TiO2 photocatalyst was prepared through co-sol-gel method used for photocatalytic degradation of methyl orange. PEG1000 was used as a template. Photocatalytic degradation was conducted after adsorption equilibrium to identify the contribution of both adsorption and photocatalytic degradation. While PEG addition ranged from 0.25 g to 1.0 g, the optimum addition amount was at 0.5 g. The degradation rate increased with increasing calcination temperature in the range from 400 to 500 oC, and then it decreased with still increasing temperature. The photocatalyst calcinated at 500 oC for 4 h could degrade 29.2% of the initial methyl orange in 30 min. Nearly 96.5% of decoloration of the initial methyl orange was removed in 100 min under UV light irradiation with the existence of the porous SiO2-doped TiO2.

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Mingjie Ma ◽  
Weijie Guo ◽  
Zhengpeng Yang ◽  
Shanxiu Huang ◽  
Guanyu Wang

TiO2/fine char (FC) photocatalyst was prepared via sol-gel method with tetrabutyl titanate as the precursor and FC as the carrier. The structural property of TiO2/FC photocatalyst was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the photocatalytic activity of TiO2/FC was evaluated by photocatalytic degradation of rhodamine B (RhB) aqueous solution under UV light irradiation. The results showed that TiO2was successfully coated on the surface of FC, and the TiO2/FC photocatalyst had better photocatalytic efficiency and stability for degradation of RhB under UV light illumination as compared to that of the pure TiO2and FC. The study provided a novel way for the application of FC to the photocatalytic degradation of organic wastes.


2015 ◽  
Vol 72 (8) ◽  
pp. 1341-1347
Author(s):  
Jinwook Chung ◽  
Seu-Run Kim ◽  
Jong-Oh Kim

CdS doped TiO2 nanotube composite was fabricated by chemical bath deposition, and was characterized by the structural, spectral and photoelectrochemical properties. The results of the structural and spectral properties showed that CdS particles were successfully deposited onto the surface of TiO2 nanotube. It is demonstrated that CdS doped TiO2 nanotube composite improved the light harvesting ability. Power conversion efficiency of about 0.32% was observed. This value is about 2.9 times higher than that of pure TiO2 nanotube. The CdS doped TiO2 nanotube composite possesses relatively higher photocatalytic activity and photodegradation efficiency than that of pure TiO2 nanotube under UV light irradiation, and the degradation efficiency of methyl orange was about 42% at UV intensity of 32 W.


2017 ◽  
Vol 19 (2) ◽  
pp. 191
Author(s):  
D. Chenchik ◽  
J. Jandosov

In this work, the nanosized magnetic Fe3O4@SiO2@TiO2 photocatalyst was prepared by sol-gel methods. First the nuclei of magnetite nanoparticles were prepared by co-precipitation of iron (II&III) salts solutions. Secondly, the magnetite nanoparticles were dispersed in ethanol using sonication, and solutions of both ammonia and tetraethoxysilane were added to the suspension under intense stirring, since it was suggested that the introduction of an intermediate passive SiO2 layer between the Fe3O4 and TiO2 phases inhibits the direct electrical contact and hence prevents the photodissolution of the magnetite phase and deterioration of the surface photocatalytic properties. Finally, solution of tetrabutoxytitanium was added dropwise to the mixture of Fe3O4@SiO2 nanoparticles under sonication & intense stirring. The resulting particles were separated using a magnet, washed and dried to constant weight, the yield was 70%. The photocatalytic activity of Fe3O4@ SiO2@TiO2 nanoparticles was investigated by photodegradation of methyl orange in aqueous solution under UV light irradiation. The photodegradation dynamics revealed that even though the oxidation rate decreases over time, about 90% of methyl orange is oxidized during the first 35 min.


2011 ◽  
Vol 295-297 ◽  
pp. 1129-1132 ◽  
Author(s):  
Shi De Wu ◽  
You Qi Zhu ◽  
Chao Li ◽  
Ying Liang Wei

A novel CuO-TiO2 composite photocatalyst was prepared by a redox process coupling with sol-gel method. The morphology and structure of the as-prepared samples were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Photocatalytic activity of the CuO-TiO2 composite photocatalyst was evaluated in terms of the degradation of Methyl orange (MO) in aqueous solution under UV light irradiation. The results show that the as-prepared composite consisted of monoclinic-phase CuO-nanotubes and TiO2 nanoparticles, in which TiO2 nanoparticles were dramatically decorated on the CuO-nanotubes, exhibits a high catalytic activity to decolorize MO. According to the experimental results, 1.27wt % was the optimal loading for CuO-doped TiO2 photocatalyst.


2011 ◽  
Vol 230-232 ◽  
pp. 131-135
Author(s):  
Wen Jie Zhang ◽  
Yang Yu

The amounts of ethanol, HCl and H2O, and also calcination conditions during sol-gel process of preparing TiO2 photocatalyst were investigated. Methyl orange adsorption on TiO2 prepared using different sol compositions is not more than 4% by varying the amount of ethanol, HCl and H2O. The photocatalytic degradation is related to sol composition, and the optimal composition is composed of 10 ml ethanol, 1.0 ml H2O, and 0.1 ml HCl. Calcination temperature and time are also important in TiO2 preparation. The TiO2 particle prepared at 500 °C for 3 h has the optimal photocatalytic activity. In the irradiation time range up to 100 min, photocatalytic degradation rate constantly increases up to 94.2%.


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.


Chemosphere ◽  
2007 ◽  
Vol 66 (11) ◽  
pp. 2142-2151 ◽  
Author(s):  
Wen-Chi Hung ◽  
Ssu-Han Fu ◽  
Jeou-Jen Tseng ◽  
Hsin Chu ◽  
Tzu-Hsing Ko

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