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Polymer modification of titania nanomaterials can provide media dispersibility and various functionalities onto the titania surface. Herein, we report the direct in situ polymer modification of the surface of titania nanotubes (TNTs) and titania nanoparticles (TNPs) via ultraviolet (UV)‐irradiated radical polymerization without any pretreatment of titania. The resulting polymer‐modified TNTs and TNPs dispersed well in solvents. The characterization of the products using various techniques including Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy‐energy dispersive X‐ray spectroscopy confirmed the successful modification of the TNT and TNP surfaces by the polymers produced via UV‐irradiated radical polymerization. The polymers on the titania surface were isolated by dissolving titania using hydrofluoric acid and analyzed by means of size exclusion chromatography and matrix‐assisted laser desorption/ionization‐time of flight‐mass spectrometry. The polymer‐modified TNTs and TNPs maintained their photocatalytic activity in dye degradation under UV irradiation. Moreover, glycopolymer‐modified TNTs were successfully prepared using the UV‐irradiated polymerization system. The glycopolymer retained its lectin biding affinity on the TNT surface. [ABSTRACT FROM AUTHOR]

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All electron density functional theory‐based calculations are carried out to investigate the properties of metal/oxide nanostructures taking the case of a Ru13 cluster supported on an octahedral anatase (TiO2)84 nanoparticle, as a representative system. The interaction between both systems is exothermic showing binding energies below −4 eV. In spite of the large interaction, the structure of the (TiO2)84 nanoparticle remains unaltered. However, the metal‐support interaction promotes the deformation of the Ru13 cluster atomic structure. This deformation is more accentuated when the Ru13 nanocluster is situated in the facet region of the (TiO2)84 nanoparticle than when the interaction involves the edge regions. The formation of the Ru13/(TiO2)84 heterostructure leads to a decrease of the energy gap inherent to the bare (TiO2)84 nanoparticle, becoming almost negligible. This is due to the contribution of the partially filled Ru 4d orbitals with Kohn–Sham energies spanning in the energy range of those of the O 2p occupied and Ti 3d empty manifolds. This feature is systematically observes no matter the interaction involves the oxide nanoparticle facet or edge regions. This study constitutes a first step in designing a strategy to investigate metal‐semiconductor nanostructures using realistic models that go beyond the use of extended surfaces. [ABSTRACT FROM AUTHOR]

The biodegradation of low-density Polyethylene (LDPE) is usually time-consuming, In the presence of Titania-nanoparticles, LDPE is photocatalytically degraded in smaller fragments afterward the bacteria can effectively degrade polyethylene. In the current study, potent polyethylene degrading bacteria were screened from the soil of the local dumpsite and identified using 16s rRNA sequencing. The protein-coated titania nanoparticle (TNPs) was synthesized using Sol-gel Method and characterized by XRD, and SAED-HRTEM. The photocatalytic biodegradation of LDPE (30 microns) in presence of 1M NaOH was studied by exposing it to UV irradiation, visible light, and high temperature (50°C) for 21 days separately and photocatalytic biodegradation was assessed by monitoring % weight loss at every 7 days' time interval, tensile strength, and FTIR. After 21 days of photocatalytic biodegradation, LDPE film containing both TNPs and Lactobacillus plantarum along with 1M NaOH in presence of visible light was unveiled oxidation and enumerated via the occurrence of strong absorptions band of the carbonyl group (C=O) and also the breaking and weakening of existing absorptions bonds along with the new carbonyl functional group formation. The decline in tensile strength was measured at 21% after 21 days. Thus, experimental results on LDPE after exposure to visible irradiation along with Lactobacillus plantarum and 5% protein-coated TNP showed improvement in degradation rate and elongation 59 % and 51% within 21 days, respectively in comparison to another study (49 % Weight loss and 12% elongation after 45 days). An excellent application of this research is significantly reduced plastic waste via a maintained procedure. [ABSTRACT FROM AUTHOR]

Carbon-metal oxide (CMO) nanocomposites have seen increasing research due to their extraordinary properties for energy storage materials and photocatalysts. Flame aerosol synthesis provides a promising route to producing CMO nanocomposites. Various CMO nanocomposites have been successfully synthesized through flame aerosol techniques in laboratories. However, a detailed understanding of the formation and growth mechanisms of such materials is lacking. Therefore, in this study, the reactive force-field molecular dynamics (ReaxFF MD) was deployed to gain atomic insights into the initial stage of carbon coating on the titania nanoparticle. We performed a large number of simulations of carbon coating with 18 typical hydrocarbon species in flames including aliphatics of C1–C4 species and polycyclic aromatic hydrocarbons (PAHs) at temperatures ranging from 400 K to 2500 K. We found that the titania nanoparticle can not only serve as a nucleus for physical adsorption of the surrounding hydrocarbons, but also can form C Ti/O bonds with them, and abstract H atoms from the surrounding hydrocarbons. The optimal temperature range for carbon coating is T ≤ 1200 K , because C Ti/O bonds are unstable at higher temperatures. At T ≥ 1500 K , hydrocarbons tend to gather to form larger carbonaceous species instead of coating onto the particle surface, as the formation of C–C bonds is promoted at high temperatures. Small aliphatics are favored to be chemically coated on the particle, while PAH molecules tend to be physically absorbed on the nanoparticle surface due to their stable electronic structure and large size. Coating tendencies of aliphatics are closely related to the number of C–C triple bonds. [Display omitted] • The roles of chemisorption and physical adsorption during C coating are compared. • The optimal temperature range for carbon coating is T ≤ 1200 K. • A carbon coating mechanism for both aliphatic and PAH species is proposed. • The number of C–C triple bonds in an aliphatic species affects its coating capability. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation employing metal oxides, such as TiO2 nanoparticles, as catalysts is an important technique for the removal of synthetic dyes from wastewater under light irradiation. The basic principles of photocatalysis of dyes, the effects of the intrinsic photoactivity of a catalyst, and the conventional non-fundamental factors are well established. Recently reported photocatalysis studies of dyes in single, binary, and ternary solute solutions opened up a new perspective on competitive photocatalytic degradation of the dyes. There has not been a review on the photocatalytic behavior of binary or ternary solutions of dyes. In this regard, this current review article summarizes the photocatalytic behavior of methylene, rhodamine B, and methyl orange in their binary or ternary solutions. This brief overview introduces the importance of the dynamics of immobilization and reactivity of the dyes, the vital roles of molecular conformation and functional groups on their diffusion onto the catalyst surface, and photocatalytic degradation, and provides an understanding of the simultaneous photocatalytic processes of multiple dyes in aqueous systems. [ABSTRACT FROM AUTHOR]

Amongst the environmental issues throughout the world, organic synthetic dyes continue to be one of the most important subjects in wastewater remediation. In this paper, the photocatalytic degradation of the dimethylmethane fluorescent dye, Auramine O (AO), was investigated in a heterogeneous aqueous solution with 100 nm anatase TiO2 nanoparticles (NPs) under 365 nm light irradiation. The effect of irradiation time was systematically studied, and photolysis and adsorption of AO on TiO2 NPs were also evaluated using the same experimental conditions. The kinetics of AO photocatalytic degradation were pseudo-first order, according to the Langmuir–Hinshelwood model, with a rate constant of 0.048 ± 0.002 min−1. A maximum photocatalytic efficiency, as high as 96.2 ± 0.9%, was achieved from a colloidal mixture of 20 mL (17.78 μmol L−3) AO solution in the presence of 5 mg of TiO2 NPs. The efficiency of AO photocatalysis decreased nonlinearly with the initial concentration and catalyst dosage. Based on the effect of temperature, the activation energy of AO photocatalytic degradation was estimated to be 4.63 kJ mol−1. The effect of pH, additional scavengers, and H2O2 on the photocatalytic degradation of AO was assessed. No photocatalytic degradation products of AO were observed using UV–visible and Fourier transform infrared spectroscopy, confirming that the final products are volatile small molecules. [ABSTRACT FROM AUTHOR]

Researches on the transformer oil-based nanofluids to determine its suitability for replacing the conventional liquid insulation has been consistently happening for more than a decade. Yet, to prepare an optimum blend of transformer oil-based nanofluid with the stability compliance and superior breakdown (BD) characteristics is still a key issue to be addressed. So to achieve the higher BD voltages (BDVs) with good stability, the nanoparticle and surfactant weights dispersed in the oil should be optimised to at least possible critical levels. In this work, dielectric BD characteristic of mineral oil dispersed with TiO(2) nanoparticle and surfactant cetyl trimethyl ammonium bromide (CTAB) is been studied with the applied AC and DC high voltages, which is termed as titania-based transformer nanofluid (TTNF) for this study. Series of TTNF samples were synthesised with different weights of TiO(2) nanoparticle and CTAB, and the partial discharge inception voltage, AC and DC BDV were experimented to ascertain the optimum concentration level. Results show that the AC and DC BDV enhanced up to 36.23 and 43.07%, respectively, for the TTNF prepared with 0.00562 wt% of TiO(2) and its 1% weight of CTAB, which was stable for around eight weeks.

Titanium dioxide is an n-type semiconductor widely used in applications like catalysts, optoelectonic materials, ceramics, H 2 generation, self-cleaning, water purification and solar cells. Sol–gel method has been chosen for nanoparticle synthesis because of its easy stoichiometry control, cost effectiveness and low temperature synthesis. In this study, titanium dioxide nanoparticles doped with different amounts of manganese (Mn) and nitrogen (N) were synthesized with sol–gel method. Crystal structure of undoped, Mn-doped, and Mn–N-codoped nanoparticles were determined with X-ray diffraction (XRD) analysis. Fourier transform infrared spectroscopy (FTIR) analysis was performed to identify the functional groups of nanoparticles. Photocatalytic analysis was caaried out by methylene blue degredation under UV light for 1 h. X-ray photoelectron spectroscopy (XPS) analysis was conducted to identify the chemical state and composition of the nanoparticles. Compared to the undoped TiO 2 , which had 79.37% efficiency, Mn-doped and Mn–N-codoped TiO 2 nanoparticles have shown greater photocatalytic efficiency with 86.25 and 99.11% efficiencies, respectively. The results confirm that doping of manganese and nitrogen has affirmative effect on phptocatalytic properties of synthesized nanoparticles. [ABSTRACT FROM AUTHOR]

Titania nanoparticle-loaded mesoporous silica has been studied as a promising photocatalytic material for the removal of organic pollutants. However, the synthesis methods and photodegradation properties have not yet been optimized. In this study, titania-loaded mesoporous silica (SBA-15) was synthesized using a layer-by-layer (LbL) assembly method. The photodegradation properties were compared to those of materials produced by the conventional synthesis method based on sol–gel reactions for the decomposition of sodium dodecylbenzylsulfate. The LbL-synthesized samples exhibit enhanced photocatalytic performance compared to that of the sol–gel samples. The total degradation amount after 5 h of UV irradiation increased by approximately 63%–108%, and the apparent first-order rate constant increased by a factor of approximately 2.4. They also presented higher photocatalytic performances during reusability tests comparing other samples. The titania nanoparticles were mainly localized on the external surface of the silica in the LbL-synthesized samples, which is more beneficial for photodegradation than infiltrated inside the mesopores in the sol–gel samples. The results of this study can be of use for the design of photocatalytic nanomaterials for environmental applications. Unlabelled Image • The layer-by-layer (LbL) method produces a shell-shaped titania on mesoporous silica. • Titania produced by the LbL method exhibits enhanced photodegradation performances. • The accessibility of the titania is more critical than the specific surface area. [ABSTRACT FROM AUTHOR]

A novel Cu 3 (PO 4 ) 2 /TiO 2 nanoparticle (TNP)/CuO nanocomposite with an excellent natural solar-light-driven photocatalytic H 2 production performance was synthesized using a sol-gel method. The 1%Cu 3 (PO 4 ) 2 /TNP/CuO catalyst displayed a better photocatalytic H 2 production yield (59.5 mmolg −1 ; natural solar light; 151 times higher than that of TNP under the optimal conditions; catalyst dosage of 0.010 g and 5% aqueous glycerol concentration) than TNP, CuO/TNP, Cu 3 (PO 4 ) 2 /TNP, and various Cu 3 (PO 4 ) 2 loadings in the Cu 3 (PO 4 ) 2 /TNP/CuO catalysts. The improved photocatalytic H 2 yields could be attributed to a suppressed recombination of charge carriers, preferable visible absorption ability, crystallinity, strong interactions, and high surface areas of 1%Cu 3 (PO 4 ) 2 /TNP/CuO, which were confirmed using X-ray diffraction, temperature programmed reduction, diffuse reflectance spectroscopy, transmission electron microscopy (TEM), high-resolution TEM, Brunauer-Emmett-Teller surface area analysis, elemental mapping, energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, electron paramagnetic resonance spectroscopy, Raman spectroscopy, photoluminescence, and photocurrent techniques. The 1%Cu 3 (PO 4 ) 2 /TNP/CuO catalyst could also contribute to the enhanced photostability and recyclability towards the photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

In this study, the synthesis, morphology, gas transport and thermal properties of novel functional aromatic polyimides and polyimide/titania nanohybrid films were investigated. The novel dianhydride containing functional trifluoromethyl groups was prepared in two steps by the nucleophilic substitution reaction, and it was fully characterized by different techniques. The tensile stress-strain of the hybrids was investigated, and the resulting nanocomposites showed good mechanical properties. The permeability and selectivity of the PI/TiO membranes as a function of the titania weight percentage were studied, and the results indicated that the permeabilities of CO and N increase with increasing the titania content. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Titania nanoparticles were fabricated by sol–gel reaction and supercritical carbon dioxide drying. The solvent inside wet gel obtained from sol–gel reaction was exchanged to organic solvents, acetone, 1-butanol and N -methylpyrrolidone before the supercritical drying. The wet gels exchanged by organic solvents were dried in supercritical carbon dioxide at 313 K and 10.0 and 20.0 MPa. It is found that the structures of the titania nanoparticles were like nano-needle. The minor-axis sizes of the nano-needle titania nanoparticles were measured by a scanning electron microscope observation. The wet gel exchanged by 1-butanol results in the smallest minor-axis of titania nanoparticles, 97 nm in the supercritical drying at 313 K and 20.0 MPa. The drying of the wet gel exchanged with N -methylpyrrolidone exhibit the reduction of the minor-axis of titania nanoparticle larger than those with acetone and 1-butanol, 181 to 103 nm by increase of pressure, 10.0 to 20.0 MPa. [ABSTRACT FROM AUTHOR]

Laccase enzyme was immobilized on titania nanoparticles and the resulting nanoparticles (ILTN) were characterized with various techniques: FTIR and SEM. ILTN was used to degrade three anionic dyes (Direct Red 31 (DR31), Acid Blue 92 (AB92), and Direct Green 6 (DG6)) from aqueous solution, individually and in binary systems. The effect of various parameters ( e.g., ILTN dosage, pH, and dye concentration) on decolorization was evaluated and the optimized conditions were determined. The amount of ILTN, reaction time, and pH for decolorization of DR31, AB92 and DG6 was 0.1 g (for DR31 and DG6) and 0.3 g (for AB92), 20 min, and pH 3 in single systems and 0.3 g, 20 min and pH 3 in binary systems, respectively. Decolorization followed Michaelis-Menten kinetics. [ABSTRACT FROM AUTHOR]

In this study, the synthesis, morphology, and thermal properties of new poly(ether imide)/titania nanohybrid films were investigated. The novel diamine containing functional nitrile groups was prepared in two steps by the nucleophilic substitution reaction and it was fully characterized by different techniques. Reaction of this diamine with pyromellitic dianhydride and 4-aminobenzoic acid gave poly(ether imide) with carboxylic acid end groups. This acid functionalized poly(ether imide) was condense with different amount of TiO 2 nanoparticles to provide organic-inorganic bonding, and the flexible films of these hybrid were prepared. The obtained materials were characterized by Fourier transform-infrared spectroscopy, thermogravimetry analysis (TGA), differential scanning calorimetry, X-ray powder diffraction, UV–Vis spectroscopy, field emission-scanning electron microscopy, and transmission electron microscopy (TEM) techniques. TEM of the nanohybrid films with 12% of TiO 2 contents confirms well dispersion of nanoparticles in the polymer matrix. TGA data indicated that the thermal behavior of the hybrid materials was increased with an increasing the content of TiO 2 nanoparticles. The tensile stress–strain of the hybrids was investigated and the resulting nanocomposites showed good mechanical properties. The permeability and selectivity of the PEI/TiO 2 membranes as a function of the titania weight percentage were study and the results indicated that the permeabilities of CO 2 and N 2 increase with increasing the titania content. [ABSTRACT FROM AUTHOR]

The low-energy dispersion of nanomaterials in the bead-milling process is examined. The effect of milling parameters including bead size, rotation speed, and milling time on the dispersibility of fragile rod-type titanium dioxide nanoparticles is investigated. From experimental data obtained for the morphological, optical, and crystalline properties of dispersed nanoparticles, an unbroken primary particle dispersion in colloidal suspension was obtained only by conducting the bead-milling process using the optimum milling parameters. Deviation from the optimum conditions (i.e., higher rotation speed and larger bead size) causes re-agglomeration phenomena, produces smaller and ellipsoidal particles, and worsens crystallinity and physicochemical properties, especially the refractive index, of the dispersed nanoparticles. We also found that decreases in refractive index induced by the milling process are related to collisions forming broken particles and the amorphous phase on the surface of the particles. In addition, the present low-energy dispersion method is prospective for industrial applications, confirming almost no impurity (from breakage of the beads) was apparent in the final product. [ABSTRACT FROM AUTHOR]

In this paper, soy meal hull activated carbon (SMHAC) and titania nanoparticle (TiO) were used as catalysts to degrade dyes. Activated carbon was prepared using soy meal hull. Degradation of dyes using single and binary catalyst systems was studied. Textile dyes were used as model pollutants. Photocatalytic dye degradation and mineralization were studied using UV-Vis spectrophotometer and ion chromatography (IC). The effects of pH, initial dye concentration, and salt on dye degradation were investigated. Dye solutions were decolorized completely (100 %). The presence of salts decreased dye degradation rate. Degradation of dyes followed first order kinetics model. Formate, acetate, and oxalate were detected as dominant aliphatic intermediates during dye degradation process. Nitrate, sulfate, and chloride anions were detected as dye mineralization products. [ABSTRACT FROM AUTHOR]

In this paper, carbon nanotube (CNT) and titania nanoparticle (n-TiO) were used to degrade dyes using single (UV/CNT/HO and UV/n-TiO/HO) and binary catalyst (UV/CNT/n-TiO and UV/CNT/n-TiO/HO) systems. Direct Red 23 and Direct Red 31 were used as model dyes. The surface characteristics of CNT were investigated using Fourier transform infrared and scanning electron microscopy. Photocatalytic dye degradation was studied using UV-Vis spectrophotometer and ion chromatography. The effects of initial dye concentration and salt on dye degradation were investigated. Formate, acetate and oxalate were detected as dominant aliphatic intermediates. Nitrate and sulfate were detected as dye mineralization products. The results indicated that the UV/CNT/n-TiO/HO could be used as an eco-friendly process to degrade dyes. [ABSTRACT FROM AUTHOR]

Abstract: A low temperature hydrothermal process have been developed to synthesize titania nanorods (NRs) and nanoparticles (NPs) with controlled size for dye sensitized solar cells (DSSCs). Effect of calcination temperature on the performance of TiO2 nanoparticles for solar cells was investigated and discussed. The crystallite size and the relative crystallinity of the anatase phase were increased with increasing the calcination temperature. The structures and morphologies of both (TiO2 nanorods and nanoparticles) were characterized using XRD, SEM, TEM/HRTEM, UV–vis Spectroscopy, FTIR and BET specific surface area (S BET) as well as pore-size distribution by BJH. The size of the titania nanorods was 6.7nm width and 22nm length while it was 13nm for nanoparticles. Efficiency of dye-sensitized solar cells (DSSCs) fabricated with oriented TiO2 nanorods was reported to be more superior compared to DSSC based on mesoporous TiO2 nanoparticles due to their high surface area, hierarchically mesoporous structures, low charge recombination and fast electron-transfer rate. With increasing calcination temperature of the prepared nanopowders, the light-electricity conversion efficiency (η) decreased. The efficiency of the assembly solar cells was decreased due to the agglomeration of the particles and difficulty of electron movement. The power efficiency was enhanced from 1.7% for TiO2 nanoparticles cells at hydrothermally temperature 500°C and 5.2% for TiO2 nanoparticles cells at hydrothermally temperature 100°C to 7.2% for TiO2 nanorods cells under AM1.5 illumination (100mWcm−2). [Copyright &y& Elsevier]

Abstract: Boron-doped TiO2 (B/TiO2) nano-materials were synthesized by a sol–gel method and characterized by X-ray diffraction pattern (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrum (FT-IR) and UV–vis diffuse reflectance spectra (DRS). With the test of bacterial inhibition zone, the antibacterial properties of B/TiO2 nano-materials on Escherichia coli were investigated. The results show that the structure of TiO2 could be transformed from amorphous to anatase and then to rutile by increasing calcination temperature; part of the boron atoms probably have been weaved into the interstitial TiO2 structure or incorporated into the TiO2 lattice through occupying O sites, whereas others exist as B2O3. The results of antibacterial experiment under visible light irradiation show that the B/TiO2 nano-materials exhibit enhanced antibacterial efficiency compared with non-doped TiO2. Ultimately, the action mechanism of B/TiO2 doping is discussed. [Copyright &y& Elsevier]

Abstract: Electrospun nanofibrous membranes (ENMs) are considered as a state of the art in water filtration technology mainly owing to their high interconnected porosity and tunable pore size assumed to offer a very high permeability also selectivity. However, the extremely high surface area makes the ENMs prone to mechanical breakdown and lack of wettability lowering the filtration efficiency. Hence, any attempt to enhance both the mechanical properties and hydrophilicity of the ENMs is highly recommended. In the current study, the structural and transport properties of polyethersulfone (PES) ENMs were modified through incorporation of titania (TiO2) nanoparticles via a sol–gel approach. Presence of titania precursor increased the conductivity of the electrospun solution thereby optimized the structural features of the electrospun mat in terms of formation of very thin beadless nanofibers, a higher porosity and smaller pore size. Moreover, a significant rise in mechanical properties, thermal stability and switching from a highly hydrophobic membrane to a superhydrophilic one occur simultaneously. The combination of a more optimum porosity, very high mechanical properties and hydrophilicity leads to a significantly higher water permeability in the TiO2/PES ENMs encouraging us to propose it as a water filtration membrane with longer life span and lower energy consumption. [Copyright &y& Elsevier]

Abstract: A simple and sensitive method for amplified chemiluminescent immunoassay has been developed by using multiple signal antibodies functionalized titania nanoparticle as tracer. This nanocomposite was fabricated by sequentially conjugating bovine serum albumin and horseradish peroxidase-labeled antibody onto the surface of titania nanoparticles using glutaraldehyde as the linkage. After a sandwich immuno-binding process, the captured nanocomposite tracer greatly catalyzed the luminol chemiluminescence reaction to produce a strong signal. Human IgG was detected as a model analyte, and a linear range of 0.5–200ngmL−1 was obtained. The detection limit of the proposed method was 0.1ngmL−1, which was 50-folds lower than that using the traditional tracer. The reproducibility, the stability and the specificity of the proposed immunoassay method were acceptable. The results for real sample analysis also demonstrated its application potential in some important areas such as clinical diagnosis. [Copyright &y& Elsevier]

We present a sol-gel derived anatase titania nanoparticle system which can be spin-coated to form thin films having high refractive index and excellent optical clarity. Stable titania suspensions were obtained through peptization of crude product in the presence of tetramethylammonium hydroxide. The particle sizes and morphologies were finely controlled by mild hydrothermal treatment at 200°C. Three titania suspensions obtained by different hydrothermal reaction time showed stable suspensions without significant flocculation, and subsequently spin coated on the glass substrates. Without calcinations step, the resulting films exhibited fairly good optical clearance and refractive indices as high as 2.05. Narrow dispersity of the particle size and the stability of titania suspension also enabled the fabrication of inverse opal structure by templating method which could be further utilized as various applications such as photonic bandgap materials and photoelectrode for solar cells. [ABSTRACT FROM AUTHOR]

Abstract: Novel chitosan/titanium dioxide (CS/TiO2) nanocomposite membranes were prepared using tetrabutyl titanate (TBT) as precursor and acetyl acetone as chelating agent by in situ sol–gel process, and characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetry (TG). The characterization results demonstrated that nano-sized TiO2 particles dispersed homogeneously within the CS matrix, which could be assigned to the hydrogen and titanoxane bonds formed between CS and TiO2. Moreover, the pervaporation performance of these membranes was investigated using the separation of ethanol–water mixture as model system. Compared with CS/TiO2 hybrid membranes prepared by blending method, most of CS/TiO2 nanocomposite membranes prepared by in situ sol–gel process exhibited higher permeation flux and separation factor under the identical conditions. Among all the prepared membranes, CS/TiO2 nanocomposite membrane containing 6wt% TiO2 exhibited the best pervaporation performance, whose averaged permeation flux and separation factor were 0.340kgm−2 h−1 and 196 for 90wt% aqueous solution of ethanol at 80°C, respectively. [Copyright &y& Elsevier]

Abstract: Titanium dioxide nanotubes were directly fabricated from commercial P25 TiO2 via alkali hydrothermal transformation. The prepared titanate nanotubes were successfully used as an electrode material for dye-sensitized solar cells (DSCs). A metal-free organic dye (indoline dye D102) was used as a sensitizer. The used indoline dye D102 is of high purity (⩾98%) and high absorption coefficient (67,500Lmol−1 cm−1 at 501nm). The TiO2 pastes were prepared with PEG (Mw 20,000) and as-made TiO2 nanotubes or P25 powders. Titania thin films were grown by screen printing method. High conversion efficiencies of light to electricity of around 9.8% and 7.6% under illumination of simulated AM1.5 sunlight (100mW/cm2) were achieved with P25 and TiO2 nanotube cells, respectively. The fill factor of DSCs based on TiO2 nanotubes increased in comparison with that of DSCs based on TiO2 nanoparticles. The electron transport and dye adsorption properties in both titanate nanotube and P25 electrodes were evaluated in terms of photovoltaic characteristics of the fabricated cells. The related mechanisms were discussed. The study provides a promising method for the development of high-efficiency and low-cost DSCs. [Copyright &y& Elsevier]

Degradation and mineralization of two agricultural organic pollutants (Diazinon and Imidacloprid as N-heterocyclic aromatics) in aqueous solution by nanophotocatalysis using immobilized titania nanoparticles were investigated. Insecticides, Diazinon and Imidacloprid, are persistent pollutants in agricultural soil and watercourses. A simple and effective method was developed to immobilization of titania nanoparticles. UV–vis, ion chromatography (IC) and chemical oxygen demand (COD) analyses were employed. The effects of operational parameters such as H2O2 and inorganic anions (NO3 −, Cl− and SO4 2−) were investigated. The mineralization of Diazinon and Imidacloprid was evaluated by monitoring of the formed inorganic anions. The selected pollutants are effectively degraded following first order kinetics model. Results show that the nanophotocatalysis using immobilized titania nanoparticle is an effective method for treatment Diazinon and Imidacloprid from contaminated water. [Copyright &y& Elsevier]

Abstract: In this paper, a liquid-phase hydrolization method to synthesize nanometer rutile titania directly without transformation from anatase is proposed. By utilizing this method, the particle size of the rutile titania nanoparticles can be controlled by adjusting the reaction conditions, e.g. the concentration of sodium hydroxide solution, reaction temperature, and calcining temperature of the powder. These titania nanoparticles have been used for the preparation of a novel composite insulation coating for magnet wires. First results showed that the lifetime of the modified nanomagnet wire in the inverter-fed motor could be prolonged to eight times compared with the non-modified wire. [Copyright &y& Elsevier]

The conventional melt quenching method was used to synthesis erbium and samarium ions co-doped sulfophosphate glasses containing TiO 2 nanoparticles with the molar compositions of (58.0-x)P 2 O 5 -20.0MgO-20.0ZnSO 4 -1.0Sm 2 O 3 -1.0Er 2 O 3 -xTiO 2 with x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0 mol%. The X-ray diffraction (XRD) technique was applied to verify that the nature of fabricated glass samples is of amorphous type. Judd-Ofelt (JO) intensity (Ω i) parameters were determined through spectral data provided in the investigations conducted on the optical absorption. The applied JO parameterization illustrates the covalency related to rare-earth (RE) ions and ligands. For some given lasing levels, the radiative parameters were estimated including branching ratios (β R), radiative lifetimes (τ R), and radiative transition probabilities (A). The photoluminescence spectra provided in some studies are used to evaluate the stimulated emission cross-sections (σ p E) for some important lasing transitions including 4G 5/2 → 6H 5/2 , 4G 5/2 → 6H 7/2 , and 4G 5/2 → 6H 9/2. The determined radiative parameters are potential options as a candidate for lasing. • Erbium and samarium ions co-doped sulfophosphate glasses containing TiO 2 nanoparticles glasses were prepared. • The average size of the TNPs was obtained 18 ± 1 nm. • Intensified Raman signal can be related to the contribution of SPR that results in an enlarged local electric field. • PMZSE0.8Ti glass sample can be considered as an effective option in the photonic applications. [ABSTRACT FROM AUTHOR]