Preparation and Photocatalytic Activity of Mixed Phase Anatase/rutile TiO2 Nanoparticles for Phenol Degradation

2014 ◽  
Vol 70 (2) ◽  
Author(s):  
Mohamad Azuwa Mohamed ◽  
Wan Norharyati Wan Salleh ◽  
Juhana Jaafar ◽  
Norhaniza Yusof
Keyword(s):  
Photocatalytic Activity ◽  
Tio2 Nanoparticles ◽  
High Performance ◽  
Sol Gel ◽  
Phenol Degradation ◽  
Chemical Properties ◽  
Mixed Phase ◽  
Rutile Tio2 ◽  
Physico Chemical ◽  
Degussa P25

The evolution of desirable physico-chemical properties in high performance photocatalyst materials involves steps that must be carefully designed, controlled, and optimized. This study investigated the role of key parameter in the preparation and photocatalytic activity analysis of the mixed phase of anatase/rutile TiO2 nanoparticles, prepared via sol-gel method containing titanium-n-butoxide Ti(OBu)4 as a precursor material, nitric acid as catalyst, and isopropanol as solvent. The prepared TiO2 nanoparticles were characterized by means of XRD, SEM, and BET analyses, and UV-Vis-NIR spectroscopy. The results indicated that the calcination temperature play an important role in the physico-chemical properties and photocatalytic activity of the resulting TiO2 nanoparticles. Different calcination temperatures would result in different composition of anatase and rutile. The photocatalytic activity of the prepared mixed phase of anatase/rutile TiO2 nanoparticles was measured by photodegradation of 50 ppm phenol in an aqueous solution. The commercial anatase from Sigma-Aldrich and Degussa P25 were used for comparison purpose. The mixed phase of anatase/rutile TiO2 nanoparticles (consists of 38.3% anatase and 61.7% rutile) that was prepared at 400°C exhibited the highest photocatalytic activity of 84.88% degradation of phenol. The result was comparable with photocatalytic activity demonstrated by Degussa P25 by 1.54% difference in phenol degradation. The results also suggested that the mixed phase of anatase/rutile TiO2 nanoparticles is a promising candidate for the phenol degradation process. The high performance of photocatalyst materials may be obtained by adopting a judicious combination of anatase/rutile and optimized calcination conditions.

scholarly journals Facile Formation of Anatase/Rutile TiO2 Nanocomposites with Enhanced Photocatalytic Activity

Molecules ◽  
2019 ◽  
Vol 24 (16) ◽  
pp. 2996 ◽  
Author(s):  
Jing He ◽  
Yi-en Du ◽  
Yang Bai ◽  
Jing An ◽  
Xuemei Cai ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Tio2 Nanoparticles ◽  
Crystal Surface ◽  
Sol Gel ◽  
Average Particle Size ◽  
Mixed Phase ◽  
Average Particle ◽  
Light Illumination ◽  
Potential Candidate ◽  
Rutile Tio2

Anatase/rutile mixed-phase TiO2 nanoparticles were synthesized through a simple sol-gel route with further calcination using inexpensive titanium tetrachloride as a titanium source, which effectively reduces the production cost. The structural and optical properties of the prepared materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-vis adsorption. The specific surface area was also analyzed by Brunauer–Emmett–Teller (BET) method. The anatase/rutile mixed-phase TiO2 nanocomposites containing of rod-like, cuboid, and some irregularly shaped anatase nanoparticles (exposed {101} facets) with sizes ranging from tens to more than 100 nanometers, and rod-like rutile nanoparticles (exposed {110} facets) with sizes ranging from tens to more than 100 nanometers. The photocatalytic activities of the obtained anatase/rutile mixed-phase TiO2 nanoparticles were investigated and compared by evaluating the degradation of hazardous dye methylene blue (MB) under ultraviolet light illumination. Compared to the commercial Degussa P25-TiO2, the mixed-phase TiO2 nanocomposites show better photocatalytic activity, which can be attributed to the optimal anatase to rutile ratio and the specific exposed crystal surface on the surface. The anatase/rutile TiO2 nanocomposites obtained at pH 1.0 (pH1.0-TiO2) show the best photocatalytic activity, which can be attributed to the optimal heterojunction structure, the smaller average particle size, and the presence of a specific exposed crystal surface. The enhanced photocatalytic activity makes the prepared anatase/rutile TiO2 photocatalysts a potential candidate in the removal of the organic dyes from colored wastewater.

scholarly journals Green Synthesis of N/Zr Co-Doped TiO2 for Photocatalytic Degradation of p-Nitrophenol in Wastewater

Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 235
Author(s):  
Hayette Benkhennouche-Bouchene ◽  
Julien G. Mahy ◽  
Cédric Wolfs ◽  
Bénédicte Vertruyen ◽  
Dirk Poelman ◽  
...  
Keyword(s):  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Sol Gel ◽  
Visible Region ◽  
Chemical Properties ◽  
Pure Tio2 ◽  
Molar Ratio ◽  
Xps Spectra ◽  
Doped Tio2 ◽  
Co Doped

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.

Sol-gel synthesized rutile TiO2 nanoparticles loaded with Cardamom essential oil: Enhanced antibacterial activity

2021 ◽  
pp. 102581
Author(s):  
Oussama Ouerghi ◽  
Mohammed H. Geesi ◽  
Elmutasim O. Ibnouf ◽  
Mohammad Javed Ansari ◽  
Pravej Alam ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Essential Oil ◽  
Tio2 Nanoparticles ◽  
Sol Gel ◽  
Rutile Tio2

Comparative Study of Physico-Chemical Properties of Pure Polyurethane and Polyurethane Based on Castor Oil

2014 ◽  
Vol 983 ◽  
pp. 39-43
Author(s):  
M. A. Alaa ◽  
Kamal Yusoh ◽  
S.F. Hasany
Keyword(s):  
Castor Oil ◽  
High Performance ◽  
In Situ Polymerization ◽  
Chemical Properties ◽  
Strength Properties ◽  
Hydroxyl Group ◽  
Physico Chemical ◽  
Analysis Technique ◽  
Hydrophobic Nature ◽  
Poly Propylene

Petroleum based polyurethanes are contributing major portions in the world requirement. To overcome the environmental issues and price adaptability, there is always a massive demand of utilization of renewable resources for polyurethane synthesis with comparable physico-chemical properties. Castor oil is the only major natural vegetable oil that contains a hydroxyl group (-OH) and unsaturated double bonds (C=C) in its organic chain and therefore can be employed with or without modification due to the excellent properties derived from the hydrophobic nature of triglycerides. In this study, physico-chemical properties of high performance polyurethane synthesized from Poly propylene glycol (PPG) in comparison with a combination of PPG and Castor oil (a renewable source), by in situ polymerization technique has been studied. The variations in properties of both types of polyurethanes are evaluated by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Thermogravimetric analysis technique (TGA). Tensile strength properties were investigated by Film Tensile testing equipment. Results indicated the presence of large-CH stretching in castor oil mixed polyurethane with a larger oxidative thermal stability, over a pure PPG polyurethanes. Tensile properties were found almost comparable in pure and mixed polymers, which signify the usage of mixed polymer in coming future, to overcome the environmental and economical crisis in polyurethanes synthesis.

scholarly journals In situ sol-gel synthesis of hyaluronan derivatives bio-nanocomposite hydrogels

2019 ◽  
Vol 6 (5) ◽  
pp. 249-258 ◽  
Author(s):  
U D’Amora ◽  
A Ronca ◽  
M G Raucci ◽  
S M Dozio ◽  
H Lin ◽  
...  
Keyword(s):  
Sol Gel ◽  
Chemical Properties ◽  
Filler Concentration ◽  
Similar Degree ◽  
Nanocomposite Hydrogels ◽  
Physico Chemical ◽  
Inorganic Fillers ◽  
Sol Gel Synthesis ◽  
Physical Blending

Abstract The main driving idea of the present study was the comparison between two different chemical modifications of hyaluronic acid (HA) followed by the development of nanocomposite hydrogels directly in situ by biomineralization of photocrosslinkable HA polymers through sol-gel synthesis. In this way, it has been possible to overcome some limitations due to classical approaches based on the physical blending of inorganic fillers into polymer matrix. To this aim, methacrylated and maleated HA, synthesized with similar degree of substitution (DS) were compared in terms of mechanical and physico-chemical properties. The success of in situ biomineralization was highlighted by reflect Fourier transform infrared spectroscopy and thermogravimetric analysis. Furthermore, mechanical characterization demonstrated the reinforcing effect of inorganic fillers evidencing a strong correlation with DS. The swelling behavior resulted to be correlated with filler concentration. Finally, the cytotoxicity tests revealed the absence of toxic components and an increase of cell proliferation over culture time was observed, highlighting these bio-nanocomposite hyaluronan derivatives as biocompatible hydrogel with tunable properties.

scholarly journals Technologies and Formulation Design of Polysaccharide-Based Hydrogels for Drug Delivery

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3156 ◽  
Author(s):  
Giulia Auriemma ◽  
Paola Russo ◽  
Pasquale Del Gaudio ◽  
Carlos A. García-González ◽  
Mariana Landín ◽  
...  
Keyword(s):  
Sol Gel ◽  
Chemical Properties ◽  
Drying Methods ◽  
Special Focus ◽  
Porous Network ◽  
Hydrogel Particles ◽  
Physico Chemical ◽  
Droplet Production ◽  
Inflammatory Drugs ◽  
Sol Gel Transition

Polysaccharide-based hydrogel particles (PbHPs) are very promising carriers aiming to control and target the release of drugs with different physico-chemical properties. Such delivery systems can offer benefits through the proper encapsulation of many drugs (non-steroidal and steroidal anti-inflammatory drugs, antibiotics, etc) ensuring their proper release and targeting. This review discusses the different phases involved in the production of PbHPs in pharmaceutical technology, such as droplet formation (SOL phase), sol-gel transition of the droplets (GEL phase) and drying, as well as the different methods available for droplet production with a special focus on prilling technique. In addition, an overview of the various droplet gelation methods with particular emphasis on ionic cross-linking of several polysaccharides enabling the formation of particles with inner highly porous network or nanofibrillar structure is given. Moreover, a detailed survey of the different inner texture, in xerogels, cryogels or aerogels, each with specific arrangement and properties, which can be obtained with different drying methods, is presented. Various case studies are reported to highlight the most appropriate application of such systems in pharmaceutical field. We also describe the challenges to be faced for the breakthrough towards clinic studies and, finally, the market, focusing on the useful approach of safety-by-design (SbD).

Explaining the Enhanced Photocatalytic Activity of Degussa P25 Mixed-Phase TiO2Using EPR

2003 ◽  
Vol 107 (19) ◽  
pp. 4545-4549 ◽  
Author(s):  
Deanna C. Hurum ◽  
Alexander G. Agrios ◽  
Kimberly A. Gray ◽  
Tijana Rajh ◽  
Marion C. Thurnauer
Keyword(s):  
Photocatalytic Activity ◽  
Mixed Phase ◽  
Degussa P25

Cement Bonded Sol-Gel TiO2 Powder Photocatalysis for Phenol Removal

2015 ◽  
Vol 776 ◽  
pp. 271-276 ◽  
Author(s):  
Nor Hafizah ◽  
Iis Sopyan
Keyword(s):  
Anatase Phase ◽  
Sol Gel ◽  
Phenol Degradation ◽  
Xrd Analysis ◽  
Hydrolysis Rate ◽  
Molar Ratio ◽  
Synthesis Process ◽  
Phenol Removal ◽  
Titanium Tetraisopropoxide ◽  
Degussa P25

Photocatalysis has been proven effective in controlling various environmental problems originated by pollutions both in liquid and gaseous phases. Titanium dioxide (TiO2) is well known the most practical photocatalyst as it has high photocatalytic efficiency, low band gap energy, and no toxicity. Various chemical methods have been tried to produce TiO2 photocatalyst powder with high activity. In this study, sol-gel method has been employed to produce nanosized TiO2 photocatalyst particles and its physical properties and photocatalytic activity in phenol degradation test were compared with the commercial TiO2 powder, Degussa P25. The synthesis process was carried out through hydrolysis of titanium tetraisopropoxide (TPT) and methanol where the molar ratio of water to TPT was monitored to control the hydrolysis rate. From X-Ray Diffraction (XRD) analysis, the sol-gel TiO2 powder obtained was fully in anatase structure with high crystallinity. Scanning Electron Microscope (SEM) measurement showed that the powder was in nanoto sub-micron size, spherical in shape, and tightly agglomerated. Thermal analysis confirmed that sol-gel derived amorphous TiO2 powder transformed to anatase phase after 400°C calcination. The test on photocatalytic performance conducted using aqueous solution of phenol as the representative of water pollutant examined in this study showed that the sol-gel TiO2 powder is more efficient in degrading phenol compared to one of the most active photocatalysts commercially available, Degussa P25.

Cetyltrimethylammonium Bromide-Assisted Hydrothermal Synthesis of Mixed-Phase TiO2 Nanorod and its Photocatalytic Activity

2014 ◽  
Vol 918 ◽  
pp. 12-16 ◽  
Author(s):  
Bin Sun ◽  
Xiu Ling Xu ◽  
Guo Wei Zhou
Keyword(s):  
Photocatalytic Activity ◽  
Cetyltrimethylammonium Bromide ◽  
Removal Rate ◽  
Weight Fraction ◽  
Mixed Phase ◽  
Molar Ratio ◽  
Structure Directing Agent ◽  
Transmission Electron ◽  
Ultraviolet Light Irradiation ◽  
Degussa P25

TiO2nanorods were successfully fabricated via hydrothermal method using cetyltrimethylammonium bromide (CTAB) as the structure-directing agent. The synthesized samples were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), and field-emission scanning electron microscope (FESEM). The study showed that as-prepared samples were the mixed crystalline phase of rutile and brookite. The weight fraction of rutile and brookite in the mixed-phase were accurately tuned by changing the concentration of CTAB. The morphology of prepared samples was TiO2nanorods with the diameter of 2530 nm and the length of 80150 nm. The samples for degradation of papermaking wastewater under ultraviolet light irradiation showed better photocatalytic activity than the commercial Degussa P25. HRT-3 prepared from CTAB: TBT molar ratio of 0.48 exhibited the highest photocatalytic activity, achieving 47.2% CODcrremoval rate and 89.5% chroma removal rate under irradiation 12 h.

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