scholarly journals Synergic combination of the sol–gel method with dip coating for plasmonic devices

2015 ◽  
Vol 6 ◽  
pp. 500-507 ◽  
Author(s):  
Cristiana Figus ◽  
Maddalena Patrini ◽  
Francesco Floris ◽  
Lucia Fornasari ◽  
Paola Pellacani ◽  
...  
Keyword(s):  
Low Cost ◽  
Sol Gel ◽  
Silica Coating ◽  
Dip Coating ◽  
Fine Tuning ◽  
Plasmonic Nanostructures ◽  
Silica Layer ◽  
Surface Protection ◽  
Regeneration Time ◽  
Plasmonic Structures

Biosensing technologies based on plasmonic nanostructures have recently attracted significant attention due to their small dimensions, low-cost and high sensitivity but are often limited in terms of affinity, selectivity and stability. Consequently, several methods have been employed to functionalize plasmonic surfaces used for detection in order to increase their stability. Herein, a plasmonic surface was modified through a controlled, silica platform, which enables the improvement of the plasmonic-based sensor functionality. The key processing parameters that allow for the fine-tuning of the silica layer thickness on the plasmonic structure were studied. Control of the silica coating thickness was achieved through a combined approach involving sol–gel and dip-coating techniques. The silica films were characterized using spectroscopic ellipsometry, contact angle measurements, atomic force microscopy and dispersive spectroscopy. The effect of the use of silica layers on the optical properties of the plasmonic structures was evaluated. The obtained results show that the silica coating enables surface protection of the plasmonic structures, preserving their stability for an extended time and inducing a suitable reduction of the regeneration time of the chip.

scholarly journals Development of Silane-Based Coatings with Zirconia Nanoparticles Combining Wetting, Tribological, and Aesthetical Properties

Coatings ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 368 ◽  
Author(s):  
Sara Lopez de Armentia ◽  
Mariola Pantoja ◽  
Juana Abenojar ◽  
Miguel Martinez
Keyword(s):  
Stainless Steel ◽  
Wear Resistance ◽  
Sol Gel ◽  
Dip Coating ◽  
Zro2 Nanoparticles ◽  
High Wear Resistance ◽  
Surface Protection ◽  
Main Research ◽  
Aesthetic Appearance ◽  
Zirconia Nanoparticles

Silane-based coatings with nanoparticles have been widely used in applications related to surface protection. Between them, the improvement of corrosion resistance by increasing the hydrophobicity is one of the main research goals. However, most coatings present problems of low wear resistance and poor aesthetic appearance. Therefore, the overall goal of this research is to manufacture hydrophobic sol-gel coatings based on silanes which comply with good tribological and aesthetical properties. In the present study, stainless steel plates were coated with a silane-based solution containing zirconia nanoparticles by dip coating. Water–ethanol solutions with silanes (methyltrimethoxysilane (MTS) and tetrathoxysilane (TEOS)) and different percentages of ZrO2 nanoparticles were prepared. Gloss, color, contact angle, surface energy, wear resistance, and thickness of coating were analyzed to elucidate the effect of zirconium oxide on the performance of the coatings. Results demonstrate that the ZrO2–silane coatings on stainless steel offer a balanced combination of properties: low wettability, high wear resistance, and similar color and brightness compared to pristine stainless steel.

An Effective Approach to Improve the Oxidation Resistance of Ti-6Al-4V Alloy by Combination of Phosphorization and Silica Coating

2011 ◽  
Vol 148-149 ◽  
pp. 534-537
Author(s):  
Chun Xiang Gao
Keyword(s):  
Oxidation Resistance ◽  
Cyclic Oxidation ◽  
Oxidation Behavior ◽  
Sol Gel ◽  
Synergetic Effect ◽  
Silica Coating ◽  
Dip Coating ◽  
Sio2 Coating ◽  
Amorphous Sio2 ◽  
Dip Coating Technique

A very effective approach to improve the oxidation resistance of Ti-6Al-4V alloy was proposed. The Ti-6Al-4V alloy was firstly phosphated and then coated by silica using sol-gel dip-coating technique. A duplex layer of TiP2O7 and amorphous silica was synthesized at the alloy surface. The isothermal and cyclic oxidation behavior of the treated alloy with silica coating and the corresponding bare alloy was investigated at 600 oC in static air to investigate the synergetic effect of phosphorization and amorphous SiO2 coating on the oxidation resistance of the alloy. The isothermal and cyclic oxidation resistances of the alloy were greatly improved.

Fabrication of polysiloxane-modified polyurethane sponge as low-cost organics/water separation and selective absorption material

2016 ◽  
Vol 74 (8) ◽  
pp. 1936-1945 ◽  
Author(s):  
Zhengshan Cui ◽  
Wanxia He ◽  
Jun Liu ◽  
Wei Wei ◽  
Liang Jiang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Mechanical Stability ◽  
Low Cost ◽  
Sol Gel ◽  
Dip Coating ◽  
Selective Absorption ◽  
Large Area ◽  
Water Separation ◽  
Good Thermal Stability ◽  
Polyurethane Sponge

Through sol-gel and dip-coating processes, commercial polyurethane sponge modified by polysiloxane was fabricated under low temperature (60 °C) and atmosphere. The contact angle of the obtained polysiloxane/polyurethane sponge is 145 ± 5°. Hence, the polysiloxane/polyurethane sponge could float on water and selectively absorb organics from the surface of the water, indicating simultaneous properties of hydrophobicity and oleophilicity. The absorbent maximum value is 50–150 times of its own weight. The polysiloxane/polyurethane sponge exhibited excellent recyclability, which could be reused by squeezing the sponge due to its high mechanical stability and flexibility. Thermogravimetry-differential thermal analysis test indicated that the polysiloxane/polyurethane sponge exhibited good thermal stability and the stable contact angle of samples tested under increasing temperature indicated its good weather resistance. Due to the commercial property of polyurethane sponge and easy-handling of polysiloxane, the polysiloxane/polyurethane sponge can be easily scaled up to recover a large-area oil spill in water and further work based on the designed equipment has been under consideration.

scholarly journals Photostability and Durability Properties of Photochromic Organosilica Coating on Fabric

2014 ◽  
Vol 9 (3) ◽  
pp. 155892501400900 ◽  
Author(s):  
Marzieh Parhizkar ◽  
Yan Zhao ◽  
Xunagi Wang ◽  
Tong Lin
Keyword(s):  
Coating Layer ◽  
Sol Gel ◽  
Dip Coating ◽  
Silica Sol ◽  
Silica Layer ◽  
Durability Properties ◽  
Coated Fabric ◽  
Coating Method ◽  
Hydrophobic Treatment ◽  
Dip Coating Method

Photochromic fabrics were prepared by a dip-coating method using a silica sol-gel solution containing photochromic dyes. The coated fabric showed a rapid photochromic response. Three methods; incorporating a UV stabilizer in the coating layer, hydrophobic treatment of the porous surface, and covering the coating layer with an additional silica layer; were used to improve the photostability and durability. All three treatments improved the photostability without noticeably changing the photochromic response/fading speeds. Most of the treatments reduced the washing and abrasion durability. The extra coating layer increased the fabric rigidity.

scholarly journals Tin Whisker Growth Suppression Using NiO Sublayers Fabricated by Dip Coating

2022 ◽  
Vol 7 (1) ◽  
pp. 7
Author(s):  
Jacob D. Buchanan ◽  
Vamsi Borra ◽  
Md Maidul Islam ◽  
Daniel G. Georgiev ◽  
Srikanth Itapu
Keyword(s):  
Nickel Oxide ◽  
Whisker Growth ◽  
Low Cost ◽  
Sol Gel ◽  
Dip Coating ◽  
Tin Whisker ◽  
Coating Method ◽  
Short Circuits ◽  
Dip Coating Method ◽  
Nickel Oxide Films

Whiskers are small crystalline growths, which can grow from certain metals or alloys. Reaching up to several millimeters long, whiskers have the potential to cause device failures due to short circuits and contamination by debris. Tin (Sn) is one such metal that is particularly prone to whisker development. Until the 2006 RoHS Initiative, lead (Pb) was added to tin in small amounts (up to 2%) to greatly reduce the growth of whiskers. Since then, however, industry has switched to lead-free tin solders and coatings, and the issue of whisker growth on tin has attracted new interest. A reactive-sputtering-deposited nickel oxide sublayer was shown recently to strongly suppress the growth of whiskers from an overlaying tin layer. This paper reports on using nickel oxide films, obtained by a sol–gel dip coating method, as whisker suppressing sublayers. The proposed method is simple, low-cost, and can easily be scaled up for manufacturing purposes. The properties of the sol–gel deposited nickel oxide film were examined using SEM, EDS, and Raman spectroscopy. Samples containing the nickel oxide sublayer were observed through SEM periodically over several months to examine the surfaces for whisker development, and the results show that such layers can be very effective in suppressing whisker growth.

scholarly journals Hydrogen Separation Using Silica-Based Composite Membranes

2014 ◽  
Vol 1051 ◽  
pp. 107-111 ◽  
Author(s):  
Mohammed Nasir Kajama ◽  
Ngozi Claribelle Nwogu ◽  
Edward Gobina
Keyword(s):  
Sol Gel ◽  
Composite Membranes ◽  
Dip Coating ◽  
Gas Permeation ◽  
Hydrogen Gas ◽  
Silica Layer ◽  
Permeate Flux ◽  
Free Silica ◽  
Feed Pressure ◽  
Ar Gas

Silica sol-gel membranes have been developed for moderate temperature (300 °C) separation of hydrogen (H2) from nitrogen (N2), methane (CH4) and argon (Ar) gas molecules. Tubular ceramic support with 15 nm nominal pore diameter and 45% porosity was modified by dip-coating method. Gas permeation characteristics were evaluated. Defect free silica layer over the substrate for hydrogen gas separation was obtained. Hydrogen gas permeate flux of 4.82x10-1mol/sec m2at 1.0 barg feed pressure was obtained. Selectivities of H2over N2, CH4and Ar of 3.07, 2.23 and 3.75 at 300 °C, 200 °C and 300 °C and 0.9 barg were obtained with the silica membranes. The gas permeation and the selectivity performance of the membrane were evaluated.

Fabrication of Dye Sensitized Solar Cell Based on TiO2 Nanoparticles and Chlorophyll from Pandan Leaf as Active Layer

2012 ◽  
Vol 545 ◽  
pp. 405-409 ◽  
Author(s):  
Nurul Huda Yusoff ◽  
Mohamad Firdaus Rosle ◽  
Surani Buniran
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Active Layer ◽  
Low Cost ◽  
Sol Gel ◽  
Dye Sensitized Solar Cells ◽  
Electrical Current ◽  
Dip Coating ◽  
Dye Sensitized Solar Cell ◽  
Dye Sensitized

Dye sensitized solar cell (DSSC) is a new class of low-cost solar cell, that belongs to third generation solar cells in thin film based. It is based on a semiconductor formed between a photo-sensitized anode and an electrolyte, known as photoelectrochemical system. A lot of research has been conducted due to their interesting potential for low-cost, lightweight, disposable and having cell efficiency up to 10%. This paper reports the fabrication of dye sensitized solar cells using TiO2 nanoparticles and chlorophyll as active layer. TiO2 nanoparticles were prepared by sol-gel method while the chlorophyll was extracted from Pandanus amaryllifolius (Pandan leaf). TiO2 film was prepared on ITO coated glass using dip coating technique and then immersed overnight in the chlorophyll solution. An electrolyte solution composed of PC-LiClO4 was injected into the cell before sealed using glass that was coated with Pt as top electrode. An active area of 4.48 cm2 was fabricated by black masking the front side. The performance of the device was studied by observing the current-voltage characteristics of the device in dark at ambient temperature and under illumination of 100 mW/cm2 light. It was found that the device showed rectifier property in the dark and able to generate electrical current under light.

Low-cost deposition of cupric oxide thin films for optoelectronic applications

2018 ◽  
Vol 84 (2) ◽  
pp. 20301 ◽  
Author(s):  
Sanjay Kumar ◽  
Sudhir Saralch ◽  
Dinesh Pathak
Keyword(s):  
Cupric Oxide ◽  
Low Cost ◽  
Sol Gel ◽  
Solar Spectrum ◽  
Dip Coating ◽  
Electrical And Optical Properties ◽  
Chloride Dihydrate ◽  
Photovoltaic Applications ◽  
P Type ◽  
Dip Coating Technique

Copper oxide is a compound that has been considered significant owing to its many advantages such as easy availability of copper in huge quantity, its non-toxic nature and the good electrical and optical properties. It is p-type with bandgap range of 1.21–1.51 eV and has potential of absorption of solar spectrum. In this work, sol–gel chemistry is explored to deposit CuO using cupric chloride dihydrate (CuCl2 · 2H2O) with 5, 10 and 15% concentration of EDTA (capping agent) using low-cost dip-coating and annealed at 400 °C. The bandgap of the CuO films was found to be in the range of 1.3–1.8 eV, which is comparable with the reported values and also suggests quantum shift in these nanostructures. These investigations suggest suitability of these layers as absorber for photovoltaic applications. SEM investigation suggests the uniform growth of layers by dip-coating techniques. Capping also appears to control the grain growth as observed by electron microscopy. Sol–gel dip-coating technique is presented in this study for deposition of flat layers.

Effect of the Amorphous Silica Coating Derived by Sol-Gel Processing on the Oxidation Behavior of Ni

2009 ◽  
Vol 79-82 ◽  
pp. 671-674
Author(s):  
B.Y. Ren ◽  
Y.H. Gao ◽  
S.J. Wang ◽  
X.J. Zhang ◽  
N.X. Feng
Keyword(s):  
Thin Film ◽  
Amorphous Silica ◽  
Oxidation Rate ◽  
Oxidation Behavior ◽  
Sol Gel ◽  
Silica Coating ◽  
Isothermal Oxidation ◽  
Dip Coating ◽  
Silica Sol ◽  
Gel Processing

Amorphous silica coating was deposited on the surface of Ni by dip-coating processing from commercial silica sol. Isothermal oxidation of the coated and uncoated specimens at 973 K to 1173 K in air was conducted to investigate the effect of the silica coating on the oxidation behavior of Ni by TGA, SEM and XRD. Results of the oxidation tests showed that the oxidation rate of Ni was reduced greatly due to the applied thin film. The possible mechanism of the effect of thin film on the oxidation of Ni was discussed.

scholarly journals A Facile Strategy for Fabrication Lysozyme-Loaded Mesoporous Silica Nanotubes from Electrospun Silk Fibroin Nanofiber Templates

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1073
Author(s):  
Jingxin Zhu ◽  
Haijuan Wu ◽  
Ding Wang ◽  
Yanlong Ma ◽  
Lan Jia
Keyword(s):  
Mesoporous Silica ◽  
Silk Fibroin ◽  
Low Cost ◽  
Sol Gel ◽  
Silica Layer ◽  
Silica Nanotubes ◽  
Cost Strategy ◽  
Bet Specific Surface Area ◽  
The Hierarchical Structure ◽  
Low Cost Strategy

This paper presents a facile and low-cost strategy for fabrication lysozyme-loaded mesoporous silica nanotubes (MSNTs) by using silk fibroin (SF) nanofiber templates. The “top-down method” was adopted to dissolve degummed silk in CaCl2/ formic acid (FA) solvent, and the solution containing SF nanofibrils was used for electrospinning to prepare SF nanofiber templates. As SF contains a large number of -OH, -NH2 and -COOH groups, the silica layer could be easily formed on its surface by the Söber sol-gel method without adding any surfactant or coupling agent. After calcination, the MSNTs were obtained with inner diameters about 200 nm, the wall thickness ranges from 37 ± 2 nm to 66 ± 3 nm and the Brunauer–Emmett–Teller (BET) specific surface area was up to 200.48 m2/g, the pore volume was 1.109 cm3/g. By loading lysozyme, the MSNTs exhibited relatively high drug encapsulation efficiency up to 31.82% and an excellent long-term sustained release in 360 h (15 days). These results suggest that the MSNTs with the hierarchical structure of mesoporous and macroporous will be a promising carrier for applications in biomacromolecular drug delivery systems.

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