Preparation Of Titanium Dioxide Nanoparticles Research Articles

Preparation of titanium dioxide nanoparticles from Solanum Tuberosum peel extract and its applications

The present study describes a method for the preparation of green titanium dioxide (TiO2) nanoparticles from the peel of Solanum tuberosum, commonly known as potato, and the potato peel being a kitchen waste. The green synthesized TiO2 (G- TiO2) nanoparticles were characterized using UV-visible spectroscopy, dynamic light scattering, scanning electron microscopy, TEM, XRD, and FTIR spectroscopy. The photocatalytic activity of the G- TiO2 nanoparticles was also shown using the dye bromophenol blue. To explore the biocompatibility of the G- TiO2, the cell viability in normal as well as cancer cells was assessed. Further, the in vivo toxicity of the G- TiO2 nanoparticles was assessed using zebrafish embryos. The novelty of the present invention is to utilize kitchen waste for a useful purpose for the synthesis of titanium dioxide nanoparticles which is known to have UV light scavenging properties. Moreover, the potato peel is a natural antioxidant and possesses a skin-lightening effect. A combination of the potato peel extract and titanium dioxide prepared using the extract will have a combinatorial effect for protecting UV light exposure to the skin and lightening the skin colour.

Preparation of Titanium Dioxide Nanoparticles and PolyVinyl Pyrrolidone Polymer Films as Antibacterial, Antibiofilm against Pathogenic Bacteria on Different Surfaces

In this paper, the structural properties that included X-ray diffraction (XRD) of Polyvinyl Pyrrolidone (PVP) and PVP with titanium dioxide nanoparticles have studied. PVP still appeared amorphous structure in spite of presence of titanium dioxide nanoparticle with crystalline form. The films of pure PVP and PVP with titanium dioxide nanoparticle have been prepared by casting method and used in covering glass plates and plastic to study the effect of these films on growth of bacteria. The antibacterial effect against Staphylococcus aureus and Escherichia coli has been tested. In this study the prepared films had antibacterial effect on plastic and glass plates, the reduction of bacterial growth percentage for PVP films on plastic and glass plates reached to 60.89% and 62.5% against S. aureus and 49%, 51% against E. coli, respectively. Whereas the percentage for prepared films from a mixture of PVP with titanium dioxide nanoparticle on plastic and glass plates reached 89.42% and 86%, respectively against S. aureus and 100% , 69% against E.coli. Antibiofilm effect of PVP with titanium dioxide nanoparticle against pathogenic bacteria on catheters was studied for (4) weeks. PVP with titanium dioxide nanoparticle films had the ability to inhibit biofilm formation for pathogenic bacteria on catheters, the inhibition of biofilm percentage reached to 83.97% against S.aureus and 65.3% against E.coli after fourth week of storage. Keywords: (PVP) Polymer; TiO2 nanoparticles; Antibacterial Activity; Antibiofilm; Staphylococcus aureus and Escherichia coli; catheters.

Electron microscopic investigation and elemental analysis of titanium dioxide in sun lotion.

The objective of this research was to determine the size, shape and aggregation of titanium dioxide (TiO2 ) particles which are used in sun lotion as UV-blocker. Overall, six sunscreens from various suppliers and two reference substances were analysed by electron microscopy (EM) techniques in combination with energy dispersive X-ray spectroscopy (EDS). Because of a high fat content in sun lotion, it was impossible to visualize the TiO2 particles without previous EM sample preparation. Different defatting methods for TiO2 from sun screens were tested. A novel sample preparation method was developed which allowed the characterization of TiO2 particles with the help of EM and EDS. Aggregates of titanium dioxide with the size of primary particles varying between 15 and 40 nm were observed only in five products. In the sun lotion with the highest SPF, only few small aggregates were found. In the sun screen with the lowest SPF, the largest aggregates of TiO2 particles were detected with sizes up to 1.6 μm. In one of the sun lotions, neither TiO2 nor ZnO was found in spite of the labelling. Instead, approx. 500 nm large diamond-shaped particles were observed. These particles are composed of an organic material as only carbon was detected by EDS. A novel defatting method for sample preparation of titanium dioxide nanoparticles used in sun cosmetics was developed. This method was applied to six different sun lotions with SPF between 30 and 50+. TiO2 particles were found in only five sunscreens. The sizes of the primary particles were below 100 nm and, according to the EU Cosmetic Regulation, have to be listed on the package with the term 'nano'.

Preparation of titanium dioxide nanoparticles supported on hexagonal mesoporous silicate (HMS) modified by oak gall tannin and its photocatalytic performance in degradation of azo dye

In this study, a new type of photocatalyst, TiO2 based on hexagonal mesoporous silicate (HMS) loaded by different concentrations of natural polyphenol oak gall tannin,OGT, (TiO2–OGTx-HMS, x=0.3, 0.6, 1wt.%) was synthesized and used in batch photocatalytic experiments. The synthesized catalysts were characterized using XRD, SEM, EDX and TEM analysis. The analysis showed that tannin was immobilized on the surface of HMS and TiO2 nanoparticles were distributed well and uniform on the surface of OGT-HMS without aggregation, while TiO2 nanoprticles aggregated on the surface of tannin free HMS. The performance of TiO2–OGTx-HMS phtocatalysts for degredation of anionic dye (i.e., Direct yellow 86) in aqueous solution were also compared with the performance of TiO2 (P-25) and TiO2–HMS. TiO2–OGT0.6%-HMS Photocatalyst exhibited higher performance than that of other photocatalysts with the adsorption and degradation efficiencies of 36.7% and 92.2%, respectively. The relative high value of activation energy, 24.8kJ/mol, confirms the effect of temperature to accelerate the photocatalytic reaction. It was also shown that photocatalytic reaction follows first order kinetic and up to 120mg/l of dye solution, Langmuir–Hinshelwood (L–H) kinetic model is acceptable.

Preparation of Titanium Dioxide Nanoparticles Immobilized on Polyacrylonitrile Nanofibres for the Photodegradation of Methyl Orange

Herein, we describe the synthesis of titanium dioxide (TiO2) nanoparticles by the hydrolysis and condensation of titanium tetrachloride. The resulting nanoparticles were immobilized on polyacrylonitrile (PAN) based nanofibres by an electrospinning technique in order to allow simple isolation and reuse of titania semiconductor photocatalyst. The composite nanofibres were heat treated to convert the polymer nanofibres to carbon nanofibres and to convert amorphous TiO2to crystalline TiO2. X-ray diffraction (XRD) analysis showed that the rutile phase was the major phase and the equatorial peaks of PAN disappeared after heat treatment at 600°C. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analysis confirmed that some TiO2nanoparticles were encapsulated whereas some were surface residing on the electrospun nanofibres. The TiO2nanoparticles were found to lower the cyclization temperature of PAN as indicated by differential scanning colorimetry (DSC) and differential thermal analysis (DTA). Photocatalytic studies on the degradation of methyl orange dye under UV light irradiation showed that composite nanofibres were capable of degrading organic contaminants in water. The carbon nanofibres with surface residing titanium dioxide nanoparticles (TiO2/CNF-SR) showed the highest photocatalytic activity (59.35% after 210 minutes) due to direct contact between the TiO2photocatalyst and methyl orange.

Preparation of titanium dioxide nanoparticles modified with methacrylate and their electrophoretic properties

Titanium dioxide nanoparticles (NPs) were modified by alkyl methacrylate (alkyl = methyl, butyl, ethylhexyl, lauryl and octadecyl) through graft copolymerization at its surface, respectively. The characteristics of these products were analysed by Fourier transform infrared, thermogravimetric analysis and transmission electron microscopy. The average particle size, zeta potential and electrophoretic mobility of modified NPs were tested in Isopar dispersion system and the water contact angle was also measured. The average particle size of NPs decreased; zeta potential, hydrophobicity and the dispersion stability enhanced with the increase of alkyl chain length. The maximum values of the zeta potential of NPs modified by poly(octadecyl methacrylate) (PSMA/TiO2) electrophoretic particles reached −72.64 mV. The obtained NPs associated with carbon black were employed to prepare the display inks. An electrophoretic display prototype device based on the white–black inks was prepared. The results gave that the device based on NPs treated with poly(lauryl methacrylate) (PLMA/TiO2) presented 357 ms of quick response under an applied 5 V (DC) field.

Preparation of titanium dioxide nano-particles modified with poly (methyl methacrylate) and its electrorheological characteristics in Isopar L

In this paper, we reported a novel non-aqueous electrorheological (ER) fluid structured by TiO2 nano-particle-modified poly (methyl methacrylate) (PMMA/TiO2) dispersed in low viscosity Isopar L and its electrorheological behaviors were researched. Titanium dioxide nano-particles modified with poly (methyl methacrylate) were prepared via in situ polymerization and characterized by Fourier transform infrared, thermogravimetry, and transmission electron microscopy. The thickness of the cladding layer of nano-titanium dioxide surface was about 2∼3 nm, and the cladding rate was 1.437 %. A non-aqueous electrorheological (ER) fluid was constituted by PMMA/TiO2 particles dispersed in Isopar L. The influence of the electric field intensity, the mass concentration of the PMMA/TiO2, and the temperature on the electrorheological properties of ER fluid were discussed, respectively. The research results showed that the ER fluid performed a well rheological property when an external electric field was applied, and with the increase of the electric field intensity, from 0 to 4.5 kV/mm, the shear stress was increased from about 3 to 30 Pa. Meanwhile, the electrorheological effect and shear stress were also strengthened with temperature elevated, and the mass concentration of PMMA/TiO2 particles increased in dispersed system, respectively.

Preparation of Titanium Dioxide Nanoparticles from Electrocoagulated Sludge using Sacrificial Titanium Electrodes

A comprehensive investigation of electrocoagulation using sacrificial titanium (Ti) electrodes in wastewater was carried out. The effects of specific process variables, such as initial pH, mixing, current density, initial organic loading, and ionic/electrolyte strength were first optimized to produce recyclable Ti-based sludge. The sludge was incinerated at 600 degrees C to produce functional TiO(2) photocatalyst. X-ray diffraction analysis revealed that TiO(2) produced at optimum electrocoagulation conditions was mostly anatase structure. The specific surface area of the synthesized TiO(2) photocatalyst was higher than that of the commercially available and widely used Degussa P-25 TiO(2). Furthermore, energy dispersive X-ray and X-ray photoelectron spectroscopy analyses showed that in additional to titanium and oxygen, this photocatalyst is also composed of carbon and phosphorus. These elements were mainly doped as a substitute site for the oxygen atom. Transmission electron microscopy images exhibited sharply edged nanorods, round nanoparticles, and nanotubes with nonuniform shapes showing some structural defects. Photodecomposition of gaseous acetaldehyde by this photocatalyst was also conducted under UV and visible light irradiation to study the photocatalytic properties of the doped TiO(2) photocatalyst. While no photocatalytic activity was observed under visible light irradiation, this doped TiO(2) photocatalyst exhibited high photocatalytic activity under UV light.

Sol–gel preparation of titanium dioxide nanoparticles in presence of a linear polysaccharide

Metal oxide fine particles are widely used in industrial applications as catalysts, pigments and so on. In this work, titanium dioxide (TiO2) nanoparticles were synthesised by controlled hydrolysis of titanium alkoxide in presence of a linear polysaccharide (1–3 linked β-d-galactapyranose and 1, 4 linked 3, 6 anyhdro-α-l-galactopyranose). Spherical crystalline nanoparticles in the range of about 5–60 nm were obtained when the polysaccharide was used. The obtained nanoparticles were characterised by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM) and particle analysis distribution.

Preparation and Characterization of Stearate-Capped Titanium Dioxide Nanoparticles

The preparation of titanium dioxide nanoparticles capped with stearate by sol–gel methods is presented in this paper. The nanoparticles are characterized by Fourier transform infrared spectroscopy and by X-ray photoelectron spectroscopy. Existence of the organic layer can be confirmed by the results of characterizations, which also indicate that the inorganic nuclei and organic surface layer are linked with chemical bonds. The nanoparticles are poorly crystallized based on the X-ray diffraction pattern. The mechanism of formation of the organo-capped nanoparticles is proposed to be competitive reactions between water and stearic acid, which is similar to a polymerization and inhibition processes. A structural model for organo-capped nanoparticles is also proposed.