Preparation of mesoporous TiO2 with enhanced photocatalytic activity towards tannery wastewater degradation

2017 ◽  
Vol 75 (6) ◽  
pp. 1494-1499 ◽  
Author(s):  
Weiwei Zhao ◽  
Xiu He ◽  
Yu Peng ◽  
Hongfeng Zhang ◽  
Donglan Sun ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Oxidation ◽  
Ph Value ◽  
Uv Light ◽  
High Surface ◽  
Sodium Dodecyl ◽  
Sodium Dodecyl Benzene Sulfonate ◽  
Mesoporous Tio2 ◽  
Tannery Wastewater ◽  
Diameter Distribution

Ordered mesoporous TiO2 materials are successfully synthesized via a sol-gel route using butyl titanate as a precursor and sodium dodecyl benzene sulfonate surfactants as soft templates. The as-prepared TiO2 samples possess a relatively high surface area of 40.03 m2/g and the center of pore diameter distribution of 13.04 nm. They exhibit excellent photocatalytic activity towards degradation of organic pollutants in tannery wastewater under UV-light and natural sunlight irradiation. The effect of the catalyst dosage, the pH value of the solution and the concentration of H2O2 are discussed in detail. This work would pave an avenue for purifying various industrial wastewaters through an advanced photocatalytic oxidation process.

scholarly journals Synthesis and Characterization of CeO2-SiO2Nanoparticles by Microwave-Assisted Irradiation Method for Photocatalytic Oxidation of Methylene Blue Dye

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
R. M. Mohamed ◽  
E. S. Aazam
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Photocatalytic Oxidation ◽  
Uv Light ◽  
Irradiation Time ◽  
High Surface ◽  
Blue Dye ◽  
Methylene Blue Dye ◽  
Microwave Assisted ◽  
Small Pore

CeO2-SiO2nanoparticles were synthesized for the first time by a facile microwave-assisted irradiation process. The effect of irradiation time of microwave was studied. The materials were characterized by N2adsorption, XRD, UV-vis/DR, and TEM. All solids showed mesoporous textures with high surface areas, relatively small pore size diameters, and large pore volume. The X-ray diffraction results indicated that the as-synthesized nanoparticles exhibited cubic CeO2without impurities and amorphous silica. The transmission electron microscopy (TEM) images revealed that the particle size of CeO2-SiO2nanoparticles, which were prepared by microwave method for 30 min irradiation times, was around 8 nm. The photocatalytic activities were evaluated by the decomposition of methylene blue dye under UV light irradiations. The results showed that the irradiation under the microwave produced CeO2-SiO2nanoparticles, which have the best crystallinity under a shorter irradiation time. This indicates that the introduction of the microwave really can save energy and time with faster kinetics of crystallization. The sample prepared by 30 min microwave irradiation time exhibited the highest photocatalytic activity. The photocatalytic activity of CeO2-SiO2nanoparticles, which were prepared by 30 min irradiation times was found to have better performance than commercial reference P25.

Photocatalytic Degradation of Acetaldehyde by Sol-Gel TiO2 Nanoparticles: Effect of the Physicochemical Properties on the Photocatalytic Activity

2011 ◽  
Vol 691 ◽  
pp. 92-98 ◽  
Author(s):  
R. Carrera ◽  
A.L. Vázquez ◽  
S. Castillo ◽  
E.M. Arce Estrada
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Surface Area ◽  
Photocatalytic Oxidation ◽  
Crystal Size ◽  
Uv Light ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
Synthesis Method

Nowadays, nanostructured semiconductor materials offer promising opportunities for a new generation of materials such as TiO2nanoparticles with improved properties for their application in the environmental catalysis field. It is well known that the phocatalytic activity of the TiO2nanoparticles is strongly dependent on the surface area, crystal size, phase composition and synthesis method. Thus, the preparation conditions clearly affect the photocatalytic activity of the TiO2nanoparticles. This work deals with the study of the structure of TiO2nanoparticles that were synthesized by the sol-gel method (using isopropanol as solvent), and calcined at 200 and 500°C. The obtained samples were characterized by the XRD-Rietveld refinement, BET and TEM techniques; and tested in the photodecomposition of acetaldehyde. The evaluations were carried out at room temperature by using CH3CHO (300 ppmv), O2(2.0 %) in helium balance in a quartz glass photoreactor (gas phase) with a 365-UV light lamp. According to the results, the sample that presented the highest activity in the photocatalytic oxidation of acetaldehyde (96.4%) was the one annealed at 200 °C. This sample showed the following proportion of phases: anatase (62.88%) with a tetragonal structure (a=0.3790926, b=0.3790926, c=0.9495732) nm; and b) brookite (37.12%) with an orthorhombic structure (a=0.9167624, b=0.5416461, c=0.5210546) nm. The surface area was 189 m2/g and the average crystal size was 7.03 nm. From the results, it can be seen that this material showed high activity in the photocatalytic degradation of acetaldehyde because of: the presence of a mixture of the anatase (higher proportion) and brookite phases, nanometric crystal size and high surface area obtained in this TiO2material. According to the aforementioned, this material can be considered as a good option for the decomposition of acetaldehyde and other volatile organic compounds (VOCs) in confined spaces.

Preparation of Mesoporous TiO2 Microspheres by Ultrasonic-Hydrothermal Process and its Photocatalysis

2012 ◽  
Vol 578 ◽  
pp. 99-104
Author(s):  
Yang Lin Liu ◽  
Xue Chen Duan ◽  
Shu Yun Liu ◽  
Yan Yan Liu
Keyword(s):  
Photocatalytic Activity ◽  
Crystal Size ◽  
High Surface ◽  
Hydrothermal Process ◽  
High Surface Area ◽  
Heat Treating ◽  
Mesoporous Tio2 ◽  
Average Crystal Size ◽  
Tio2 Microspheres ◽  
Effects Of Temperature

Mesoporous TiO2 microspheres were prepared by Ultrasonic-Hydrothermal Process with tetrabutyltitanate as titanium resource and octadecylamine as template. The effects of temperature and time of hytrothermol process, and calcination temperature on the structure had been investigated via XRD,SEM,TEM.The results indicated it will be better hythrothermol treating 20h at 120°Cand then heat-treating 4h at 400°C. A high surface area of 261.7 m2/g and pore volume of 0.28cm3/g was obtained in the corresponding sample with quite narrow distribution,and centering at 4.3nm in diameter.TiO2 frame was highly crystallized, showed the characteristic of pure anataste, with average crystal size of 10.0nm. The as-prepared sample possess a morphology of microspheres with diameter about 100-300nm.The photocatalytic activity was valuated by photodegradation of methly orange. The resultes indicated 99.79% of methly orange in the solution was removed after 30min photocatalytic treatment.

scholarly journals Synthesis and Characterization of Electrospun Nanocomposite Nanofibers with Ag Nanoparticles for Photocatalysis Applications

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Srujan Mishra ◽  
S. Phillip Ahrenkiel
Keyword(s):  
Photocatalytic Activity ◽  
Ag Nanoparticles ◽  
Photocatalytic Oxidation ◽  
Uv Light ◽  
Dark Field ◽  
Mixed Phase ◽  
Methyl Red ◽  
Fiber Morphology ◽  
Electrospinning Technique ◽  
Red Dye

Polycrystalline mixed-phase TiO2nanofibers embedded with 2.0% w/v Ag nanoparticles was prepared by the electrospinning technique. Calcination of dry Ag nanoparticles-titanium (IV) isopropoxide/PVP electrospun nanofiber mats in air at for 24 h yielded polycrystalline TiO2/Ag nanofibers. The morphology and distribution of silver nanoparticles were observed by transmission electron microscopy (TEM), scanning TEM (STEM), and high-angle annular dark-field (HAADF) imaging. Mixed-phase anatase and rutile TiO2nanofibers were produced with Ag nanoparticles. High-resolution TEM lattice-fringe measurements showed good agreement with Ag (111), anatase (101), and rutile (110) phases. The photocatalytic activity of TiO2/Ag nanofibers was compared to the photocatalytic activity of pure TiO2nanofibers by studying the photodegradation of methyl red dye under UV light irradiation, in a photoreactor. UV-visible absorbance spectra showed that the rate of decay of the dye in case of photodegradation by TiO2/Ag nanofibers was 10.3 times higher than that by pure TiO2nanofibers. The retaining of the fiber morphology along with the increased surface area due to the addition of Ag nanoparticles can be believed to enhance the photocatalytic oxidation of methyl red dye.

scholarly journals Synthesis of NiFe2O4-LDH Composites with High Adsorption and Photocatalytic Activity for Methyl Orange Degradation

Inorganics ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 98 ◽  
Author(s):  
Cristian Valencia-Lopez ◽  
Mario Zafra-Calvo ◽  
María Martín de Vidales ◽  
Verónica Blanco-Gutierrez ◽  
Evangelina Atanes-Sanchez ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Photocatalytic Oxidation ◽  
Uv Light ◽  
Oh Radicals ◽  
Methyl Orange Degradation ◽  
Light Emitting ◽  
Multifunctional Material ◽  
Double Hydroxide ◽  
Remediation Process

The presence of hazardous chemicals in wastewater produced by industrial activities and human metropoles is threating the availability of safe drinking water. The development of a multifunctional material coupling adsorption and photocatalytic activity is hereby particularly promising for the removal of pollutants. We have proved the adsorption and catalytic activity of NiFe2O4-layered double hydroxide (LDH) composite through the degradation of methyl orange (MO) at room temperature under visible light. This degradation is enhanced by using a set of small light-emitting diodes (LEDs) providing a uniform 405 nm UV light. The remediation process is based on a first-step rapid adsorption of MO molecules by the LDH structures followed by the photocatalytic oxidation of the pollutant by the (·OH) radicals produced by the NiFe2O4 semiconductor nanoparticles (NPs). The magnetic properties of the ferrite NPs allow a facile separation of the composite from the liquid media via a simple magnet. NiFe2O4-LDH composite could find wide application as a highly effective adsorbent/oxidizing catalyst operating under visible or near UV light.

Hydrothermal Synthesis and Characterisation of Cu Doped TiO2 Nanotubes for Photocatalytic Degradation of Methyl Orange

2014 ◽  
Vol 911 ◽  
pp. 126-130 ◽  
Author(s):  
Mohd Hasmizam Razali ◽  
M.N. Ahmad-Fauzi ◽  
Abdul Rahman Mohamed ◽  
Srimala Sreekantan
Keyword(s):  
Electron Microscopy ◽  
Titanium Dioxide ◽  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Uv Light ◽  
High Surface ◽  
High Surface Area ◽  
Morphological Studies ◽  
Doped Titanium Dioxide ◽  
Degradation Of Methyl Orange

Copper doped titanium dioxide (Cu-TiO2) nanotubes were synthesised by hydrothermal method. The samples were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and nitrogen gas adsorption. The photocatalytic activity of the copper doped titanium dioxide nanotubes was investigated by photodegradation of methyl orange under UV light. The structural and morphological studies showed that, the copper was incorporated into interstitial positions of the TiO2lattice to form a new phase of TiO2(hexagonal). The copper doped TiO2nanotubes possessed high surface area and pore volume, results high photocatalytic activity for degradation of methyl orange (MO).

scholarly journals Preparation and photocatalytic activity analysis of nanometer TiO2 modified by surfactant

2018 ◽  
Vol 8 ◽  
pp. 184798041878197 ◽  
Author(s):  
Wenzheng Wu ◽  
Longjian Zhang ◽  
Xiaojie Zhai ◽  
Ce Liang ◽  
Kaifeng Yu
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Anatase Phase ◽  
Sol Gel ◽  
Sodium Dodecyl ◽  
Sodium Dodecyl Benzene Sulfonate ◽  
Ammonium Bromide ◽  
Transmission Electron ◽  
Cetyl Trimethyl Ammonium ◽  
Nano Titanium Dioxide

Combining the advantages of the sol–gel method and solvothermal method, the single anatase phase of nano-titanium dioxide (TiO2) with high crystallinity had been prepared by means of the sol–solvent thermal improved process, in which butyl titanate was used as titanium source; anhydrous ethanol as solvent; concentrated nitric acid as inhibitor; and cationic surfactant cetyl trimethyl ammonium bromide (CTAB), anionic surfactant sodium dodecyl benzene sulfonate (SDBS), and nonionic surfactant polyethylene glycol (PEG) as dispersants. The analysis results of Brunauer–Emmett–Teller, scanning electron microscopy, and transmission electron microscopy characterizations indicated that CTAB-modified TiO2 with the optimum ratio had the most apparent dispersibility and the highest specific surface area compared with unmodified TiO2, SDBS-modified TiO2, and PEG-modified TiO2. At the same time, the photocatalytic degradation rate of methyl orange could be improved to 99.16%. It indicated that the modification effect of CTAB was significantly better than those of SDBS and PEG, which made the nanoparticles uniformly dispersed, resulting in higher photocatalytic activity.

Synthesis and Photocatalytic Properties of Three-Dimensional Mesoporous Titanium Dioxide

NANO ◽  
2021 ◽  
Vol 16 (09) ◽  
Author(s):  
Xiao Ye ◽  
Lei Xu ◽  
Zi-Yan Li ◽  
Rui-Qi Gang ◽  
Yi Xia ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Flue Gas ◽  
Photocatalytic Oxidation ◽  
Ph Value ◽  
Uv Light ◽  
Three Dimensional ◽  
Spherical Shape ◽  
Average Diameter ◽  
Strong Light ◽  
Mesoporous Titanium Dioxide

The three-dimensional (3D) mesoporous titanium dioxide (TiO2) was synthesized by microwave-assisted hydrothermal method, using titanium sulfate as titanium source and urea to adjust pH value. Its structure and photocatalytic oxidation properties were studied. The results show that the TiO2 particles have a 3D mesoporous structure, uniform distribution and spherical shape, the average diameter is about 0.67[Formula: see text][Formula: see text]m. These properties provide strong light adsorption, high specific surface area, which increases the active site of the photocatalyst, porosity can also enhance the ability of the material to adsorb pollutants, thus has better stability. It was applied to photocatalytic degradation of 10[Formula: see text]mg/L rhodamine B (RhB) solution. After 80[Formula: see text]min of irradiation under 420[Formula: see text]nm ultraviolet (UV) light, the degradation rate of RhB reached more than 90%. In addition, it also provided an excellent photocatalytic efficiency of removing Hg0 in simulated flue gas. The removal efficiency could still reach over 86% after 40 h, which could be used in the treatment of heavy metal pollutants such as metallurgical flue gas.

Enhanced Photocatalytic Activity of N/Li2MoO4 Co-doped TiO2 Nanoparticles under Visible Light

2021 ◽  
Author(s):  
Jutarat Kwakkaew ◽  
Matthana Khangkhamano ◽  
Rungrote Kokoo ◽  
Weerachai Sangchay
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Photocatalytic Oxidation ◽  
Uv Light ◽  
Visible Region ◽  
Strong Light ◽  
Doped Tio2 ◽  
Vis Spectroscopy ◽  
Wide Range

TiO2-based nanomaterials have been extensively synthesized and used in a wide range of photocatalytic applications. The photocatalytic oxidation process, however, is only activated by irradiation with ultraviolet (UV) light which limits its indoor applications. Herein, to improve such limitations, N/Li2MoO4-doped TiO2 nanoparticles were prepared via sol-gel method. Li2MoO4 concentration was varied. The catalysts were characterized by XRD, XPS, FE-SEM, and UV-Vis spectroscopy. As-synthesized N/Li2MoO4-doped TiO2 catalysts exhibited their crystal sizes of as fine as 20 nm in diameter whereas that of the pure TiO2 was about 35 nm. The absorption ranges of the N/ Li2MoO4-doped catalysts were relocated from UV region toward visible light region. The catalyst with 1 mol% Li2MoO4 offered the highest degradation rate of methylene blue (MB) solution upon visible light irradiation. Its fine crystal size, narrow band gap energy (2.82 eV), high defect concentration, and strong light absorption in visible region are responsible for the enhanced photocatalytic activity of the 1 mol% Li2MoO4.

Synthesis of Mesoporous Titania–Silica Monolith Composites — A Comprehensive Study on their Photocatalytic Degradation of Acid Blue 113 Dye Under UV Light

2016 ◽  
Vol 15 (05n06) ◽  
pp. 1660012 ◽  
Author(s):  
Thurlapathi VL Thejaswini ◽  
Deivasigamani Prabhakaran
Keyword(s):  
Photocatalytic Activity ◽  
Dye Degradation ◽  
Uv Light ◽  
Degradation Kinetics ◽  
High Surface ◽  
Textile Dye ◽  
Silica Monoliths ◽  
Bet Analysis ◽  
Acid Blue 113 ◽  
Acid Blue

The present work deals with the synthesis of bi-continuous macro and mesoporous crack-free titania–silica monoliths, with well-defined structural dimensions and high surface area. The work also highlights their potential photocatalytic environmental applications. The highly ordered titania–silica monoliths are synthesized through direct surface template method using organic precursors of silica and titania in the presence of surface directing agents such as pluronic P123 and PEG, under acetic acid medium. The monoliths are synthesized with different Ti/Si ratios to obtain monolithic designs that exhibit better photocatalytic activity for dye degradation. The titania–silica monoliths are characterized using XRD, SEM, EDAX, FT-IR, TG–DTA and BET analysis. The photocatalytic activity of the synthesized monoliths is tested on the photodegradation of a textile dye (acid blue 113). It is observed that the monolith with 7:3 ratio of Ti/Si showed significant photocatalysis behavior in the presence of UV light. The influence of various physico-chemical properties such as, solution pH, photocatalyst dosage, light intensity, dye concentration, effect of oxidants, etc. are analyzed and optimized using a customized photoreactor set-up. Under optimized conditions, the monoliths exhibited superior degradation kinetics, with the dye dissipation complete within 10[Formula: see text]min of photolysis. The mesoporous catalysts are recoverable and reusable up to four cycles of repeated usage.

Sign in / Sign up

Export Citation Format

Share Document