Photocatalytic Degradation Glyphosate with Cerium and Nitrogen Co-Doped TiO2 under Visible Irradiation

2012 ◽  
Vol 430-432 ◽  
pp. 1048-1051 ◽  
Author(s):  
Li Lin ◽  
Xue Jun Zhang ◽  
Gu Qing Xiao ◽  
Xing Xiong

Cerium and nitrogen co-doped TiO2 nanocrystals were synthesized by a simple sol-gel process, using tetrabutyl titanate as the raw materials with (NH4)2Ce(SO4)3 and urea as ion donors. The co-doped TiO2 nanoparticles were characterized by X-ray diffraction and transmission electro microscopy. The photodegradation of glyphosate has been investigated in aqueous suspensions of doped TiO2 under visible irradiation. The results exhibit a higher thermal stability of anatase than pure TiO2.The uniform test results show the optimal conditions: nCe/nTi nN/nTi and calcining temperature was 0.08,0.01 and 800°C. The highest degradation rate for co-doped TiO2 show five times photocatalytic activity of Degussa P25.

2013 ◽  
Vol 562-565 ◽  
pp. 858-863
Author(s):  
Lan Fang Yao ◽  
Xiong Tang ◽  
Xin Pei Yan ◽  
Lin Li

Pure TiO2, Nd3+doped TiO2 and Nd 3+-CTAB co-doped TiO2 nanometer thin films were prepared by the sol-gel technique with tetrabutyl titanate and neodymium nitrate as raw materials and surfactant cetyltrimethylammonium bromide (CTAB) as template. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Visible absorbance spectroscopy (UV-Vis). The photocatalytic activity was evaluated by photocatalytic degradation of methyl orange. The results show that the all samples calcined at 500°C are all anatase, and there are slight red shifts of the Nd3+doped TiO2 and Nd3+-CTAB co-doped TiO2 films compared with pure TiO2 films and the red shift of Nd 3+-CTAB co-doped TiO2 is more obvious than that of Nd 3+ doped TiO2, which is beneficial to improve the photocatalytic efficiency. The1.0% Nd3+-CTAB co-doped TiO2 nanometer film calcined at 500°C had excellent photocatalytic efficiencies and the degradation rate of the film is more than 90% after 120 min.


Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 235
Author(s):  
Hayette Benkhennouche-Bouchene ◽  
Julien G. Mahy ◽  
Cédric Wolfs ◽  
Bénédicte Vertruyen ◽  
Dirk Poelman ◽  
...  

TiO2 prepared by a green aqueous sol–gel peptization process is co-doped with nitrogen and zirconium to improve and extend its photoactivity to the visible region. Two nitrogen precursors are used: urea and triethylamine; zirconium (IV) tert-butoxide is added as a source of zirconia. The N/Ti molar ratio is fixed regardless of the chosen nitrogen precursor while the quantity of zirconia is set to 0.7, 1.4, 2, or 2.8 mol%. The performance and physico-chemical properties of these materials are compared with the commercial Evonik P25 photocatalyst. For all doped and co-doped samples, TiO2 nanoparticles of 4 to 8 nm of size are formed of anatase-brookite phases, with a specific surface area between 125 and 280 m2 g−1 vs. 50 m2 g−1 for the commercial P25 photocatalyst. X-ray photoelectron (XPS) measurements show that nitrogen is incorporated into the TiO2 materials through Ti-O-N bonds allowing light absorption in the visible region. The XPS spectra of the Zr-(co)doped powders show the presence of TiO2-ZrO2 mixed oxide materials. Under visible light, the best co-doped sample gives a degradation of p-nitrophenol (PNP) equal to 70% instead of 25% with pure TiO2 and 10% with P25 under the same conditions. Similarly, the photocatalytic activity improved under UV/visible reaching 95% with the best sample compared to 50% with pure TiO2. This study suggests that N/Zr co-doped TiO2 nanoparticles can be produced in a safe and energy-efficient way while being markedly more active than state-of-the-art photocatalytic materials under visible light.


2018 ◽  
Vol 71 (5) ◽  
pp. 315 ◽  
Author(s):  
Xiongbo Dong ◽  
Zhiming Sun ◽  
Xiangwei Zhang ◽  
Xue Li ◽  
Shuilin Zheng

A C/N co-doped TiO2/diatomite composite with exposed (001) facet was prepared through a facile sol–gel method using tetrabutyl titanate as a titanium precursor and hexamethylenetetramine as C/N dopant. The as-prepared photocatalyst composites were characterised by X-ray diffraction (XRD), nitrogen adsorption–desorption isotherms, scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectra (DRS), photoluminescence spectroscopy (PL), as well as X-ray photoelectron spectroscopy (XPS). The TiO2 nanoparticles were immobilised and uniformly distributed on the surface of diatomite with a smaller grain size compared with pure TiO2. In addition, compared with pure TiO2 and the undoped TiO2/diatomite composite, the photocatalytic activity of the C/N co-doped TiO2/diatomite composite under solar light illumination was obviously enhanced. Results indicate that the introduction of a C/N dopant can effectively promote the growth of the highly active anatase (001) facet of TiO2. On the other hand, the N impurity was doped into the interstitial spaces of the TiO2 lattice, which accelerated the charge transfer and hindered the recombination of photogenerated electron–hole pairs. The results show that the as-prepared composite exhibited promising applications in dye wastewater degradation owing to its outstanding reusability and cost-effectiveness.


2012 ◽  
Vol 512-515 ◽  
pp. 207-210
Author(s):  
Quan Wen ◽  
Jian Feng Huang ◽  
Li Yun Cao ◽  
Jian Peng Wu

V2O5 powders were successfully synthesized by the EDTA assistanced ultrasound sol-gel process using NH4VO3 and EDTA, NH3•H2O as raw materials. The synthesized activation energy and the influence of pH values and the calcination temperatures on the phases and microstructures of powders were particularly investigated. The precursor powders and the V2O5 powders were characterized by X-ray diffraction (XRD), fourier transform inelectron microscopy (FT-IR), scanning electron microscopy (SEM) and differential scanning calorimetry-thermal gravimetric (DSC-TG). Results show that the obtained products exhibit good crystallization under the conditions of pH=4, calcination temperature 400~500 °C and calcination time 0.5 h during the synthesizing process. The as-prepared V2O5 powders show preferred growth orientation along (001) plane at the pH=4. By DSC analysis, the ultrasonic cavitation result in the decrease in synthesized activation energy obviously than that was prepared without ultrasonic irradiation.


2012 ◽  
Vol 529 ◽  
pp. 537-540 ◽  
Author(s):  
Gui Hua Li ◽  
An Feng Wang

N-La co-doped TiO2 has been synthesized via sol-gel process. The XRD result showed that the structure of N-La co-doped TiO2 was anatase. Their performance of photocatalytic degradation of methylene blue under visible light were investigated. The combined effects of catalyst compsition, calcination temperature, catalyst amount and reaction temperature on catalyst activity were investigated. Experiment results depicted that activeness of catalyst N2.5La0.5/TiO2 calcinated at 500°C for 2h was highest. Using this catalyst, when the catalyst amount was 0.35 g/L, the reaction temperature was 40°C the degradation rate of mehylene blue in 4h could reach 96.5%.


2013 ◽  
Vol 302 ◽  
pp. 176-181 ◽  
Author(s):  
Chun Hua Cao

TiO2/graphene oxide (TiO2/GO) nanocomposites were prepared by the sol-gel method using tetrabutyl titanate and graphite oxide as the main raw materials. The microstructure of TiO2/GO nanocomposites was analyzed by X-ray diffraction and transmission electron microscopy. The results showed that graphene oxide was uniformly covered with sphere-like anatase TiO2 nanoparticles, which had a diameter of about 10 nm. Reactive brilliant red X-3B (X-3B) was used as model pollutant to study the photocatalytic activity of the composites. The effect of key factors on X-3B degradation was investigated. The results indicated that the photocatalytic activity of TiO2/GO nanocomposites was higher than that of pure TiO2 and the mixture of TiO2 and graphite oxide under the same conditions, and the nanocomposites had the best photocatalytic activity, when the content of graphene oxide was 100 mg. Moreover, it was found that the rate of photocatalytic degradation decreased with the increase of the initial dye concentration, and the optimum amount of nanocomposites was 0.8g/L when the initial concentration of X-3B solution was 100 mg/L, and the degradation rate could reach 96% after 60 min irradiation.


2012 ◽  
Vol 22 (30) ◽  
pp. 15309 ◽  
Author(s):  
Xue Ping Cao ◽  
Dan Li ◽  
Wen Heng Jing ◽  
Wei Hong Xing ◽  
Yi Qun Fan

2021 ◽  
Vol 9 (1) ◽  
pp. 79-86
Author(s):  
Mursal Mursal ◽  
◽  
Nurul Azmi ◽  
Ismail Ismail ◽  
◽  
...  

The effect of Mg/La co-doping addition on the caracteristics of TiO2 as photoelectrode have been studied. This study aims to investigate the effect of Mg/La co-doping concentration on the characteristics of TiO2. This study aims investigate the effect of Mg/La co-doping concentration on the characteristics of TiO2. Mg/La was varied from 0% mol, 0.4 / 0.6% mol, and 0.6 / 0.4% mol. Synthesis of TiO2 co-doping Mg/La was done by sol gel method. The resulting of powder pure TiO2 and co-doping Mg/La was made to paste, and was deposited on a glass substrate with a size of 2.5 x 2.5 cm and sintered at 600°C for 1 hour. Mg / La co-doped TiO2 layers were characterized using XRD, UV-Vis, and FTIR spectrometers. The results showed that TiO2 was the mos dominan phase appeared in pure TiO2 sample. The phase of MgO, MgTiO3, Mg2TiO4, and La2O3 were found in Mg/La co-doped TiO2 samples. The crystal size of Mg/La co-doped TiO2 was varied from 8.85 to 7.70 nm. In this research, we obtained that the energy gap was varied from 3.52 to 3.5 eV depent on co-dopant concentration. FTIR measurement showed groups of Ti-O, Ti-O-Ti, Ti-O-O, and H-O.


2017 ◽  
Vol 748 ◽  
pp. 413-417
Author(s):  
Chun Yu Long ◽  
Fang Fang Peng ◽  
Min Min Jin ◽  
Pei Song Tang ◽  
Hai Feng Chen

Using Pr (NO3)3, butyl titanate, ethylene glycol and citric acid as main raw materials, praseodymium titanate (Pr2Ti2O7) was prepared by the sol-gel process. The samples were characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), thermal gravity-differential thermal analysis (TG-DTA), diffuse-reflection spectra (DRS) and Fourier transform infrared (FT-IR). The effect of different calcination temperature and illumination time on the photocatalytic properties of Pr2Ti2O7 was investigated. It was found that the single phase Pr2Ti2O7 could be obtained through sol-gel process and calcination at 1000 °C. The Pr2Ti2O7 samples calcination at 1000 °C were uniform , and the resulting product had a particle size of 200 nm and an optical band gap of 3.26 eV. Under ultraviolet light, the degradation of methyl orange arrived to 80.11% after 180 min of photocatalytic reaction. The Pr2Ti2O7 samples showed good photocatalytic activity for decomposition of methyl orange.


2010 ◽  
Vol 177 ◽  
pp. 54-57 ◽  
Author(s):  
Li Na Meng ◽  
Wen Yuan Xu ◽  
Ting Xu

Co doped TiO2 nanoparticles and thin films were prepared from Ti(OC4H9)4 by sol-gel method. The influence of Co-doping and its content on the crystallite structure and phase composition of TiO2 was systematically investigated by SEM and XRD, the precursor was analysed by TGA. The photocatalytic activity of nanocomposites was investigated in the photocatalytic degradation of methyl orange. The results indicated that the inhibitory effect of Co-doping on the phase transformation of TiO2 from anatase to rutile receded obviously when the calcination temperature was changed to 650°C from 550°C. Under the ultraviolet light radiation, the favourite Co-doping concentration was 1% and the obtained Co doped TiO2 thin films exhibited higher photocatalytic activity than nanoparticles and pure TiO2 in the photodegradation of methyl orange.


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