Sol-gel synthesis of boron doped TiO2/hollow glass bubbles composite powders for photocatalytic degradation of azophloxine-Effects of calcination

2020 ◽  
Vol 16 ◽  
Author(s):  
Wenjie Zhang ◽  
Yuxuan Liu
Keyword(s):  
Photocatalytic Degradation ◽  
Calcination Temperature ◽  
Sol Gel ◽  
Hollow Spheres ◽  
Degradation Efficiency ◽  
Bet Surface Area ◽  
Composite Powders ◽  
Water Separation ◽  
Doped Tio2 ◽  
Boron Doped

Background: B-TiO2 was supported on the surface of iM16K glass bubbles to achieve a suitable density for the B-TiO2/iM16K composite hollow spheres. Aeration or stirring in the wastewater can lead to thorough mixing of photocatalyst and wastewater. Solid-water separation is quite easy because the materials can float on the water surface while stopping aeration or stirring. Methods: The iM16K glass bubbles were used to prepare boron-doped B-TiO2/iM16K composite hollow spheres through a sol-gel route. The materials were characterized by X-ray diffraction, scanning electron microscope, Fourier transform infrared spectroscopy, UV-Visible diffuse reflectance spectrometry, and N2 adsorption-desorption techniques. Photocatalytic degradation of azophloxine on the composites was determined. Results: The bandgap energy of the B-TiO2/iM16K composite was slightly less than 3.0 eV when the calcination temperature was below 500oC. The sample calcined at 350oC had a BET surface area of 88.6 m2 /g, while the value of the sample calcined at 800oC was 1.2 m2 /g. The maximum photocatalytic degradation efficiency was obtained for the sample calcined at 450oC, and nearly all of the original azophloxine molecules were decomposed after 120 min of irradiation. Photocatalytic degradation efficiency after 30 min of irradiation was enhanced from 18.8% to 47.9% when B-TiO2 dosage increased from 100 to 800 mg/L. Conclusion: Crystallization of anatase TiO2 was temperature dependent, and the properties of B-TiO2/iM16K composite hollow spheres were affected by phase composition of the boron-doped TiO2 layer. The change in calcination temperature can have significant effect on photocatalytic degradation of azophloxine. The production of hydroxyl radical depended on photocatalytic activity of the B-TiO2/iM16K composite hollow spheres.

scholarly journals Synthesis, Characterization, and Evaluation of Boron-Doped Iron Oxides for the Photocatalytic Degradation of Atrazine under Visible Light

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
Shan Hu ◽  
Guanglong Liu ◽  
Duanwei Zhu ◽  
Chao Chen ◽  
Shuijiao Liao
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Iron Oxides ◽  
Visible Light Irradiation ◽  
Sol Gel ◽  
Band Gap Energy ◽  
Light Irradiation ◽  
Bet Surface Area ◽  
Boron Doped

Photocatalytic degradation of atrazine by boron-doped iron oxides under visible light irradiation was investigated. In this work, boron-doped goethite and hematite were successfully prepared by sol-gel method with trimethylborate as boron precursor. The powders were characterized by XRD, UV-vis diffuse reflectance spectra, and porosimetry analysis. The results showed that boron doping could influence the crystal structure, enlarge the BET surface area, improve light absorption ability, and narrow their band-gap energy. The photocatalytic activity of B-doped iron oxides was evaluated in the degradation of atrazine under the visible light irradiation, and B-doped iron oxides showed higher atrazine degradation rate than that of pristine iron oxides. Particularly, B-doped goethite exhibited better photocatalytic activity than B-doped hematite.

Effects of Calcination on Sol-gel Synthesis of Hollow Spherical 8%B-TiO2 for Photocatalytic Degradation of RBR X-3B -Characterization and Activity

2019 ◽  
Vol 15 (3) ◽  
pp. 289-295 ◽  
Author(s):  
Lili Yang ◽  
Yao Zhao ◽  
Jing Li ◽  
Yanwen Zhou ◽  
Xuan Xiao ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Surface Area ◽  
Calcination Temperature ◽  
Sol Gel ◽  
Degradation Process ◽  
Maximum Activity ◽  
Bet Surface Area ◽  
Tetrabutyl Titanate ◽  
Tio2 Sample ◽  
Small Surface

Background: TiO2-based materials can be utilized in both polluted air and wastewater treatments. Ion doping is the most applied modification method, and many kinds of metal ions and nonmetal ions are doped into a TiO2 crystalline skeleton. The hollow spherical photocatalyst can both easily suspend in wastewater under aeration and settle down after treatment to release the water. Methods: The hollow spherical B-TiO2 photocatalyst was prepared by a sol-gel method. Tetrabutyl titanate and tributyl borate were used as the titanium and boron sources. The materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), infrared spectrum (FTIR), and N2 adsorption-desorption techniques. Results: The 8%B-TiO2 material is composed of anatase TiO2 when the calcination temperature is below 600°C. The graphical template is burnt out during calcination to leave a hole in the spherical 8%B-TiO2. The BET surface area of the materials declines from 53.2 m2/g at 400°C to 10.6 m2/g at 700°C. High-temperature thermal treatment results in the small surface area and large pore size. The activity of the 8%B-TiO2 materials was studied on adsorption and photocatalytic degradation of RBR X-3B dye. The 8%B-TiO2 sample prepared at 600°C has the maximum activity on RBR X-3B degradation. After five cycles, decoloration efficiency on the 8%B-TiO2 decreases from 100% in the first cycle to 80% in the fifth cycle. Conclusion: Photocatalytic activity of the hollow spherical material depends on calcination temperature with the optimum activity on the sample obtained at 600°C. The hollow spherical 8%B-TiO2 has satisfactory performance for recycling. Photocatalytic degradation of RBR X-3B can be proven by the UV-Vis spectra during the degradation process.

Photocatalytic Activity of B-TiO2 Prepared Using Boric Acid as Boron Source

2012 ◽  
Vol 496 ◽  
pp. 154-157
Author(s):  
Wen Jie Zhang ◽  
Ke Xin Li
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Boric Acid ◽  
Calcination Temperature ◽  
Sol Gel ◽  
Doped Tio2 ◽  
Boron Doped ◽  
Degradation Activity ◽  
Boron Source ◽  
Activity Decrease

Boron doped TiO2 photocatalysts was prepared by sol-gel method. The influences of Boric acid amount, reaction time and calcination temperature on photocatalytic activity of the prepared B-TiO2 were studied. The boron doped TiO2 had small adsorption capacity. 38.8% of the initial methyl orange was degraded on the sample prepared with 1% B2O3 after 30 min of irradiation. After 120 min of irradiation, nearly 100% of the methyl orange was degraded on the material. Photocatalytic activities of the boron doped TiO2 materials increased from 400 oC up to 500 oC. After that, degradation activity decrease with further increase of calcination temperature in the range from 500 oC to 600 oC.

Study on photocatalytic degradation of gaseous dichloromethane using pure and iron ion-doped TiO2 prepared by the sol–gel method

Chemosphere ◽  
2007 ◽  
Vol 66 (11) ◽  
pp. 2142-2151 ◽  
Author(s):  
Wen-Chi Hung ◽  
Ssu-Han Fu ◽  
Jeou-Jen Tseng ◽  
Hsin Chu ◽  
Tzu-Hsing Ko
Keyword(s):  
Photocatalytic Degradation ◽  
Sol Gel ◽  
Iron Ion ◽  
Gel Method ◽  
Doped Tio2 ◽  
Sol Gel Method

scholarly journals Synthesis of TiO2/Pd and TiO2/PdO Hollow Spheres and Their Visible Light Photocatalytic Activity

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Jing Yan ◽  
Xiaojuan Li ◽  
Bo Jin ◽  
Min Zeng ◽  
Rufang Peng
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Diffuse Reflectance Spectroscopy ◽  
Hollow Spheres ◽  
Active Species ◽  
Degradation Efficiency ◽  
Diffraction Field ◽  
Transmission Electron

A series of TiO2, TiO2/Pd, and TiO2/PdO hollow sphere photocatalysts was successfully prepared via a combination of hydrothermal, sol-immobilization, and calcination methods. The structure and optical properties of the as-prepared samples were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Telleranalysis, Barrett-Joyner-Halenda measurement, and UV-Vis diffuse reflectance spectroscopy. The photocatalysis efficiencies of all samples were evaluated through the photocatalytic degradation of rhodamine B under visible light irradiation. Results indicated that TiO2/PdO demonstrated a higher photocatalytic activity (the photocatalytic degradation efficiency could reach up to 100% within 40 min) than the other samples and could maintain a stable photocatalytic degradation efficiency for at least four cycles. Finally, after using different scavengers, superoxide and hydroxyl radicals were identified as the primary active species for the effectiveness of the TiO2/PdO photocatalyst.

Synthesis and Photocatalytic Properties of ZnO-Volcanics Composites

2013 ◽  
Vol 331 ◽  
pp. 497-502
Author(s):  
Ai Hua Wang ◽  
Ping Che ◽  
Jie Min Liu ◽  
Gui Hua Wang
Keyword(s):  
Calcination Temperature ◽  
Physical Adsorption ◽  
Sol Gel ◽  
Degradation Efficiency ◽  
X Ray Diffraction ◽  
Photocatalytic Reactor ◽  
Decolorization Rate ◽  
Surface Areas ◽  
Transmission Electron ◽  
Average Grain Size

in this paper, nano-ZnO were synthesized via a sol-gel method, and ZnO-volcanics composites (ZVCs) were prepared via physical adsorption process. The morphology and structure of ZnO/ ZnO-volcanics composites (ZVCs) samples were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM).BET surface areas of the catalysts were determined by N2 adsorption (BET). According the data of XRD, the average grain size of ZnO is 15.1 nm consistent with the result observed by TEM (16.3 nm). Photocatalytic performance of ZnO and ZVCs were carried out in sprinkling photocatalytic reactor, with methylene blue (MB) as pollutants model. Decolorization rate is select as the evaluation parameters for the degradation effect. The effect of catalyst dosage, MB initial concentration, calcination temperature and pH on the degradation efficiency have been investigated. The MB degradation efficiency was 99.2% when the concentration of MB, the ZVCs, the pH and the calcination temperature were 10 mg/L, 20 g/L, and 10.03, 500 oC respectively. In the catalysts recycle experiments, the decolorization rate of MB using ZVCs is 90.2% after utilization for six times, overwhelmingly higher than that of ZnO (22.6%), indicating immobilization is efficient.

scholarly journals Sol-Gel Synthesis of Fe2O3-Doped TiO2 for Optimized Photocatalytic Degradation of 2,4- Dichlorophenoxyacetic Acid

2017 ◽  
Vol 33 (04) ◽  
pp. 1959-1968 ◽  
Author(s):  
Afini Razani ◽  
Abdul Halim Abdullah ◽  
Anwar Fitrianto ◽  
Nor Azah Yusof ◽  
Umar Ibrahim Gaya
Keyword(s):  
Photocatalytic Degradation ◽  
Sol Gel ◽  
Dichlorophenoxyacetic Acid ◽  
Doped Tio2 ◽  
2,4 Dichlorophenoxyacetic Acid ◽  
Sol Gel Synthesis

Synthesis and characterization of anatase TiO2 nanolayer coating on Ni–Cu–Zn ferrite powders for magnetic photocatalyst

2010 ◽  
Vol 25 (1) ◽  
pp. 134-140 ◽  
Author(s):  
Yen-Pei Fu ◽  
Wen-Ku Chang ◽  
Hsin-Chao Wang ◽  
Chung-Wen Liu ◽  
Cheng-Hsiung Lin
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Degradation ◽  
Sol Gel ◽  
Titanium Isopropoxide ◽  
Degradation Efficiency ◽  
Ferrite Powder ◽  
Order Kinetic ◽  
Magnetic Photocatalyst ◽  
The Core ◽  
Zn Ferrite

In the current research, we successfully prepared TiO2/Ni–Cu–Zn ferrite composite powder for magnetic photocatalyst. The core Ni–Cu–Zn ferrite powder was synthesized using the steel pickling liquor and the waste solution of electroplating as the starting materials. The shell TiO2 nanocrystal was prepared by sol-gel hydrolysis precipitation of titanium isopropoxide [Ti(OC3H7)4] on the Ni–Cu–Zn ferrite powder followed by heat treatment. From transmission electron microscopy (TEM) image, the thickness of the titania shell was found to be approximately 5 nm. The core of Ni–Cu–Zn ferrite is spherical or elliptical shape, and the particle size of the core is in the range of 70–110 nm. The magnetic Ni–Cu–Zn ferrite nanopowder is uniformly encapsulated in a titania layer forming core-shell structure of TiO2/Ni–Cu–Zn ferrite powder. The degradation efficiency for methylene blue (MB) increases with magnetic photocatalyst (TiO2/Ni–Cu–Zn ferrite powder) content. When the magnetic photocatalyst content is 0.40 g in 150 mL of MB, the photocatalytic activity reached the largest value. With a further increase in the content of magnetic photocatalyst, the degradation efficiency slightly decreased. This occurs because the ultraviolet (UV) illumination is covered by catalysts, which were suspended in the methylene blue solution and resulted in the inhibition in the photocatalytic reaction. The photocatalytic degradation result for the relationship between MB concentration and illumination revealed a pseudo first-order kinetic model of the degradation with the limiting rate constant of 1.717 mg/L·min and equilibrium adsorption constant 0.0627 L/mg. Furthermore, the Langmuir–Hinshelwood model can be used to describe the degradation reaction, which suggests that the rate-determining step is surface reaction rather than adsorption is in photocatalytic degradation.

Synthesis and Characterization of Hollow Anatase TiO2 Spheres and its Application in the Photodegradation of γ-Lindane under Ultraviolet Light

2014 ◽  
Vol 699 ◽  
pp. 245-250
Author(s):  
Afrouz Baharvand ◽  
Alias Mohd Yusof ◽  
Rusmidah Ali ◽  
Mohd Marsin Sanagi ◽  
Sheela Chandren ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Uv Light ◽  
Sol Gel ◽  
Hydrothermal Process ◽  
Hollow Spheres ◽  
Bet Surface Area ◽  
Tetrabutyl Titanate ◽  
Anatase Titania ◽  
Scanning Electron

Hollow anatase titania spheres have been synthesized using hydrothermally–prepared carbon spheres as the template. Here, the combination of hydrothermal process with sol–gel followed by calcination in air was done in order to obtain hollow anatase TiO2 spheres by utilizing fructose and tetrabutyl titanate (TBT) as the precursors. The structure and morphology of the products were characterized using various techniques, including Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermal gravimetric and differential thermal analysis (TG–DTA), scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). XRD showed that all peaks of TiO2 correspond to anatase crystalline phase. The BET surface area of the hollow spheres was about 22 m2g-1. The photocatalytic activity of the hollow anatase TiO2 was measured under UV light using γ-lindane as the target pollutant and was compared to commercially available TiO2.

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