scholarly journals Sol-gel-derived titanium oxide–cerium oxide biocompatible nanocomposite film for urea sensor

2009 ◽  
Vol 24 (5) ◽  
pp. 1667-1673 ◽  
Author(s):  
Anees A. Ansari ◽  
G. Sumana ◽  
M.K. Pandey ◽  
B.D. Malhotra
Keyword(s):  
Titanium Oxide ◽  
Cerium Oxide ◽  
Indium Tin Oxide ◽  
Nanocomposite Film ◽  
Sol Gel ◽  
Electrochemical Techniques ◽  
Dip Coating ◽  
Atomic Force ◽  
Coating Method ◽  
Dip Coating Method

Sol-gel-derived biocompatible titanium oxide–cerium oxide (TiO2–CeO2) nanocomposite film was deposited onto indium tin oxide (ITO)-coated glass substrate by the dip-coating method. This nanobiocomposite film has been characterized using x-ray diffraction, Fourier transform infrared, atomic force microscope, and electrochemical techniques, respectively. The particle size of the TiO2–CeO2 nanobiocomposite film was found to be 23 nm. The urea biosensor fabricated by immobilizing mixed enzyme [urease (Urs) and glutamate dehydrogenase (GLDH)] on this nanobiocomposite showed a response time of 10 s, sensitivity as 0.9165 μAcm−2mM−1, detection limit of 0.166 μM, and negligible effect due to interferants uric acid, cholesterol, glucose, and ascorbic acid. The value of Michaelis–Menten constant (Km) estimated using Lineweaver–Burke plot as 4.8 mM indicated enhancement in the affinity and/or activity of enzyme attached to their nanobiocomposite. This bioelectrode retained 95% of enzyme activity after 6 months at 4 °C.

Porous SiO2/TiO2 Bilayer Antireflection Coatings with Self-Cleaning Capacity

2011 ◽  
Vol 233-235 ◽  
pp. 2970-2974 ◽  
Author(s):  
Ruo Yu Chen ◽  
Jian Wu Wang ◽  
Hong Ning Wang ◽  
Wei Yao ◽  
Jing Zhong
Keyword(s):  
Methyl Orange ◽  
Mechanical Strength ◽  
Sol Gel ◽  
Dip Coating ◽  
Antireflection Coatings ◽  
Force Microscopy ◽  
Atomic Force ◽  
Coating Method ◽  
Self Cleaning ◽  
Dip Coating Method

The porous SiO2/TiO2bilayer antireflection coatings with self-cleaning capacity have been prepared by a sol-gel dip-coating method, the surfactant template, Pluronic F123 (PF123) was added to the sol as a pore generator. The performances of the coatings were analyzed with ultraviolet visible spectrophotometer (UV-Vis), scanning electron microscope (SEM) and atomic force microscopy (AFM). The self-cleaning function of coatings was evaluated by means of photocatalytic degradation of methyl orange in aqueous solution, and mechanical strength of the coatings has also been studied. The results indicate that the average transmittance of porous SiO2/TiO2coating increases by 6% as compared to uncoated glass, the coating has a small particle size, a porous structure and a low roughness. After illuminated by ultraviolet light for 3 h, the 5 mg/L methyl orange can be degraded by 56.5%. In addition, the coating has an excellent mechanical strength.

Synthesis and Characterization of Nanocrystalline TiO2 Thin Films by Sol-Gel Dip Coating Method

2013 ◽  
Vol 678 ◽  
pp. 108-112 ◽  
Author(s):  
Narayanaswamy Gokilamani ◽  
N. Muthukumarasamy ◽  
Mariyappan Thambidurai
Keyword(s):  
Thin Films ◽  
Sol Gel ◽  
Dip Coating ◽  
X Ray Diffraction ◽  
Tio2 Thin Films ◽  
Atomic Force ◽  
Coating Method ◽  
Nanocrystalline Titanium ◽  
Dip Coating Method

Nanocrystalline titanium dioxide (TiO2) thin films have been prepared by dip coating method. The TiO2 thin films have been coated on glass substrate and annealed at 400, 450 and 500° C respectively. The X- ray diffraction pattern shows that TiO2 nanocrystalline thin films are of anatase structure and the grain size is found to be in the range of 20-35 nm. The annealed films have been observed to be nanocrystalline in nature and the crystallinity has been observed to improve on annealing. The surface topography of the films has been studied using atomic force microscope. The optical properties have been studied using transmittance spectra. The band gap has been found to lie in the range of 3.70 to 3.83 eV depending on the annealing temperature.

Porous Gel Coatings Obtained by Phase Separation in ORMOSIL System

2000 ◽  
Vol 628 ◽  
Author(s):  
Kazuki Nakanishi ◽  
Souichi Kumon ◽  
Kazuyuki Hirao ◽  
Hiroshi Jinnai
Keyword(s):  
Phase Separation ◽  
Reaction Time ◽  
Volume Fraction ◽  
Sol Gel ◽  
Reaction Times ◽  
Dip Coating ◽  
Coating Solution ◽  
Coating Method ◽  
Gel Phase ◽  
Dip Coating Method

ABSTRACTMacroporous silicate thick films were prepared by a sol-gel dip-coating method accompanied by the phase separation using methyl-trimethoxysilane (MTMS), nitric acid and dimethylformamide (DMF) as starting components. The morphology of the film varied to a large extent depending on the time elapsed after the hydrolysis until the dipping of the coating solution. On a glass substrate, the films prepared by early dipping had inhomogeneous submicrometer-sized pores on the surface of the film. At increased reaction times, relatively narrow sized isolated macropores were observed and their size gradually decreased with the increase of reaction time. On a polyester substrate, in contrast, micrometer-sized isolated spherical gel domains were homogeneously deposited by earlier dippings. With an increase of reaction time, the volume fraction of the gel phase increased, then the morphology of the coating transformed into co-continuous gel domains and macropores, and finally inverted into the continuous gel domains with isolated macropores. The overall morphological variation with the reaction time was explained in terms of the phase separation and the structure freezing by the forced gelation, both of which were induced by the evaporation of methanol during the dipping operation.

scholarly journals The Effect of Film Thickness and Content on Film Formation from PS/ Nanocomposites Prepared by Dip-Coating Method

2012 ◽  
Vol 2012 ◽  
pp. 1-17 ◽  
Author(s):  
M. Selin Sunay ◽  
Onder Pekcan ◽  
Saziye Ugur
Keyword(s):  
Film Thickness ◽  
Elevated Temperatures ◽  
Film Formation ◽  
Fluorescence Emission ◽  
Dip Coating ◽  
Atomic Force ◽  
Annealing Step ◽  
Coating Method ◽  
Fluorescence Emission Intensity ◽  
Dip Coating Method

Steady-state fluorescence (SSF) technique in conjunction with UV-visible (UVV) technique and atomic force microscope (AFM) was used for studying film formation from TiO2covered nanosized polystyrene (PS) latex particles (320 nm). The effects of film thickness and TiO2content on the film formation and structure properties of PS/TiO2composites were studied. For this purpose, two different sets of PS films with thicknesses of 5 and 20 μm were prepared from pyrene-(P-) labeled PS particles and covered with various layers of TiO2using dip-coating method. These films were then annealed at elevated temperatures above glass transition temperature () of PS in the range of 100–280°C. Fluorescence emission intensity, from P and transmitted light intensity, were measured after each annealing step to monitor the stages of film formation. The results showed that film formation from PS latexes occurs on the top surface of PS/TiO2composites and thus developed independent of TiO2content for both film sets. But the surface morphology of the films was found to vary with both TiO2content and film thickness. After removal of PS, thin films provide a quite ordered porous structure while thick films showed nonporous structure.

Synthesis of WO3 Electrochromic Sensor by Sol-Gel Method and Characterization of Its Electrochemical and Optical Properties

2006 ◽  
Vol 317-318 ◽  
pp. 807-810 ◽  
Author(s):  
Chang Yeoul Kim ◽  
Jin Wook Choi ◽  
Tae Yeoung Lim ◽  
Duck Kyun Choi
Keyword(s):  
Thin Film ◽  
Sol Gel ◽  
Dip Coating ◽  
Xrd Pattern ◽  
Starting Solution ◽  
Oxide Crystal ◽  
Heat Treated ◽  
Coating Method ◽  
Dip Coating Method

Electrochromic WO3 thin film was prepared by using tungsten metal solution in hydrogen peroxide as a starting solution and by sol-gel dip coating method. XRD pattern showed that tungsten oxide crystal phase formed at 400. In the view of electrochemical property, WO3 thin film which was heat-treated at 300 and was amorphous had better than that of the crystalline phase.

Optical, magnetic and structural properties of Cr-doped ZnO thin films by sol–gel dip-coating method

2017 ◽  
Vol 4 (9) ◽  
pp. 096403 ◽  
Author(s):  
Zohra N Kayani ◽  
Marya Siddiq ◽  
Saira Riaz ◽  
Shahzad Naseem
Keyword(s):  
Thin Films ◽  
Structural Properties ◽  
Sol Gel ◽  
Dip Coating ◽  
Zno Thin Films ◽  
Coating Method ◽  
Doped Zno ◽  
Dip Coating Method

Effect of ZnO on a Superhydrophilic Self-Cleaning Properties of TiO2/SiO2 Thin Film on Glass Slide Substrate

2015 ◽  
Vol 1131 ◽  
pp. 237-241 ◽  
Author(s):  
Akkarat Wongkaew ◽  
Chanida Soontornkallapaki ◽  
Naritsara Amhae ◽  
Wichet Lamai
Keyword(s):  
Thin Film ◽  
Contact Angle ◽  
Visible Light ◽  
Band Gap ◽  
Sol Gel ◽  
Dip Coating ◽  
Band Gap Energy ◽  
Gap Energy ◽  
Coating Method ◽  
Dip Coating Method

This work aims to study the effect of ZnO containing in TiO2/SiO2 film on the superhydrophilic property after exposed to different types of light. The metal solutions were prepared by sol-gel technique and the film was deposited on glass slides by dip coating method. The parameter studied was the amount of ZnO in the TiO2/SiO2 film. The contents of ZnO were 5-20% weight (increased by 5%). The amount of TiO2 was constant at 30% weight. The obtained films were analyzed for their roughness. The results indicated that film roughness changed according to the ZnO contents. With 5%ZnO in the thin film, the roughness was 0.726 nm while 20%ZnO obtained the roughness of 2.128 nm. UV-Vis spectrophotometer was used for measuring of transmittance of films. At wavelength of 550 nm, the transmittances of each film were greater than 90%. Band gap energy of each film was calculated from the transmittance data. It was found that the average band gap energy of the films was 2.47 eV. Then, the films contained various amount of ZnO were grouped into 2 sets. The first set was exposed to visible light while the other set was exposed to UV. The duration of exposure was 5 hr. Both sets of films after exposed to any light were kept in a black box controlled relative humidity of 85%. Each film was measured contact angle every day. It was found that the 30%TiO2/5%Zn/SiO2 film exposed to visible light showed the best superhydrophilic property. The contact angle was about 0-5° within 3 days. This may due to the reduction of band gap energy in the presence of ZnO in TiO2/SiO2 films to 2.41 eV and the roughness of the film.

scholarly journals Sol-Gel Synthesis of TiO2/SiO2 and ZnO/SiO2 Composite Films and Evaluation of Their Photocatalytic Activity towards Methyl Green

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
V. L. Chandraboss ◽  
B. Karthikeyan ◽  
J. Kamalakkannan ◽  
S. Prabha ◽  
S. Senthilvelan
Keyword(s):  
Photocatalytic Activity ◽  
Uv Light ◽  
Sol Gel ◽  
Composite Films ◽  
Dip Coating ◽  
Methyl Green ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Coating Method ◽  
Dip Coating Method

The TiO2/SiO2 and ZnO/SiO2 composite films were prepared by sol-gel dip coating method. The surface morphology and crystal structure of thin films were characterized by means of scanning electron microscopy (SEM) with elementary dispersive X-ray analysis (EDX) and X-ray diffractometer (XRD). Optical properties of films have been investigated using ultraviolet and visible spectroscopy (UV-visible spectroscopy). The photocatalytic activity was established by testing the degradation and decolorization of methyl green (MG) from aqueous solution with artificial UV-light.

The Effect of Ceramic Substrates Surface Roughness on the Deposition of AgTiO2 Coatings

2014 ◽  
Vol 699 ◽  
pp. 9-14
Author(s):  
Zulkifli Mohd Rosli ◽  
Nur Hamizah Ahmad Rusli ◽  
Jariah Mohamad Juoi ◽  
Mazidah Zainudi
Keyword(s):  
Surface Roughness ◽  
Sol Gel ◽  
Dip Coating ◽  
Ceramic Substrates ◽  
Homogeneous Surface ◽  
Transparent Glass ◽  
Coating Method ◽  
Green Glass ◽  
Ball Clay ◽  
Dip Coating Method

This research aims to determine the effect of ceramic substrates surface roughness on the deposition of silver-titania (AgTiO2) coating. The ceramic substrates were prepared from three batch mixture of waste glass namely transparent glass (99 wt. %): carbon black (1 wt. %), green glass (85 wt. %): ball clay (15 wt. %) and transparent glass (85 wt. %): ball clay (15 wt. %) deposited with AgTiO2 using sol gel dip coating method. Ti and Ag phases have been identified via glancing angle X-Ray diffraction analysis (GAXRD). The thickness and morphology of coatings were characterized using Scanning Electron Microscopy (SEM). Analyses conducted have confirmed that AgTiO2 coating layers have been successfully deposited into various types of selected ceramic substrates. Microstructure analysis shows that coatings deposited on ceramic substrate with a moderate surface roughness of 2.13 (green glass: ball clay) produced the most homogeneous surface and uniform thickness.

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