Showing papers on "Coating published in 2012"
TL;DR: An easily fabricated, transparent, and oil-rebounding superamphiphobic coating is designed, based on low-energy surfaces and roughness on the nano- and micrometer scales.
Abstract: Coating is an essential step in adjusting the surface properties of materials. Superhydrophobic coatings with contact angles greater than 150° and roll-off angles below 10° for water have been developed, based on low-energy surfaces and roughness on the nano- and micrometer scales. However, these surfaces are still wetted by organic liquids such as surfactant-based solutions, alcohols, or alkanes. Coatings that are simultaneously superhydrophobic and superoleophobic are rare. We designed an easily fabricated, transparent, and oil-rebounding superamphiphobic coating. A porous deposit of candle soot was coated with a 25-nanometer-thick silica shell. The black coating became transparent after calcination at 600°C. After silanization, the coating was superamphiphobic and remained so even after its top layer was damaged by sand impingement.
1,710 citations
TL;DR: Graphene is established as the thinnest known corrosion-protecting coating because it suppresses metal oxidation and oxygen reduction and prevents corrosion of underlying metals.
Abstract: We report the use of atomically thin layers of graphene as a protective coating that inhibits corrosion of underlying metals. Here, we employ electrochemical methods to study the corrosion inhibition of copper and nickel by either growing graphene on these metals, or by mechanically transferring multilayer graphene onto them. Cyclic voltammetry measurements reveal that the graphene coating effectively suppresses metal oxidation and oxygen reduction. Electrochemical impedance spectroscopy measurements suggest that while graphene itself is not damaged, the metal under it is corroded at cracks in the graphene film. Finally, we use Tafel analysis to quantify the corrosion rates of samples with and without graphene coatings. These results indicate that copper films coated with graphene grown via chemical vapor deposition are corroded 7 times slower in an aerated Na2SO4 solution as compared to the corrosion rate of bare copper. Tafel analysis reveals that nickel with a multilayer graphene film grown on it corro...
1,064 citations
TL;DR: The analysis of the literature showed that many studies have focused on calcium phosphate coatings produced either using conversion or deposition methods which were developed for orthopaedic applications, however, the control of phases and the formation of cracks still appear unsatisfactory.
1,042 citations
TL;DR: The recent development of carbon coating techniques in lithium-ion batteries is discussed with detailed examples of typical cathode and anode materials and the limitation of current technology and future perspective of the new concept of "hybrid coating" are pointed out.
841 citations
TL;DR: A superhydrophobic fabric coating made of a crosslinked polydimethylsiloxane elastomer, containing well-dispersed hydrophobic silica nanoparticles and fluorinated alkyl silane shows remarkable durability against repeated machine washes, severe abrasion, strong acid or base, boiling water or beverages and excellent stain resistance.
Abstract: A superhydrophobic fabric coating made of a crosslinked polydimethylsiloxane elastomer, containing well-dispersed hydrophobic silica nanoparticles and fluorinated alkyl silane, shows remarkable durability against repeated machine washes, severe abrasion, strong acid or base, boiling water or beverages and excellent stain resistance.
559 citations
TL;DR: An overview of the different calcium phosphate phases, their properties and their behaviour in vitro and in vivo has been provided, followed by the current coating techniques used for calcium phosphates that may be or may have been adapted for magnesium substrates.
556 citations
TL;DR: It is shown that an inelastic aerogel made of single-walled carbon nanotubes can be transformed into a superelastic material by coating it with between one and five layers of graphene nanoplates, and the graphene-coated aerogels exhibits no change in mechanical properties after more than 1 × 10(6) compressive cycles.
Abstract: A mechanically fragile aerogel made of single-walled carbon nanotubes can be transformed into a superelastic material by coating it with graphene.
460 citations
TL;DR: In this paper, a reverse micro-emulsion method was used to obtain the Fe3O4@SiO2 core/shell NPs with a single core and with different shell thicknesses.
Abstract: In this work, we present the coating regulations of Fe3O4 nanoparticles (NPs) by the reverse microemulsion method to obtain the Fe3O4@SiO2 core/shell NPs. The regulation produces the core/shell NPs with a single core and with different shell thicknesses, and it especially can be applied to different sizes Fe3O4 NPs and avoid the formation of core-free silica particles. Our results reveal that the silica coating parameters suitable for Fe3O4 NPs with certain size are not definitely applicable to that with other sizes, and the match of the number of Fe3O4 NPs with aqueous domain is essential. We found that the small aqueous domain is suitable to coat ultrathin silica shell, while the large aqueous domain is indispensable for coating thicker shells. To avoid the formation of core-free silica particles, the thick silica shell can be achieved by increasing the content of either TEOS through the equivalently fractionated drops or ammonia with a decreased one-off TEOS. The ligand exchange between the intermediat...
456 citations
TL;DR: This work reports an all-solution-based fabrication of an alternative emissive device, a light-emitting electrochemical cell, using a slot-die roll-coating apparatus and features a fault-tolerant >1-μm-thick active material that is doped in situ during operation.
Abstract: The grand vision of manufacturing large-area emissive devices with low-cost roll-to-roll coating methods, akin to how newspapers are produced, appeared with the emergence of the organic light-emitt ...
412 citations
TL;DR: The recent progress of organic coatings on magnesium alloys and techniques for evaluating the performance of organic coating are reviewed in this paper, where the authors provide a comprehensive knowledge about the interface of the organic coating and developing new coating strategies.
360 citations
TL;DR: In this article, a superhydrophilic and superoleophobic nanocomposite coating is fabricated by spray casting nanoparticle-polymer suspensions on various substrates, which can be used for the separation of oil and water.
Abstract: A novel superhydrophilic and superoleophobic nanocomposite coating is fabricated by spray casting nanoparticle–polymer suspensions on various substrates. Water droplets can spread over the coating completely; meanwhile, oil droplets can roll off the coating at low tilt angles without any penetration. Besides overcoming oil-fouling problems for the hydrophilic coating, the superhydrophilic–superoleophobic coating applied to the stainless steel mesh can be used for the separation of oil and water.
TL;DR: In this paper, a review of recent works in the area of multi-level self-healing is presented, based on the controlled release of anticorrosion species from micro and nanocontainers incorporated into a polymer or hybrid coating matrix.
TL;DR: In this paper, X-ray diffraction patterns and transmission electron microscopy images confirmed the formation of PANI coating and incorporation of BaTiO3 or Fe3O4 nanoparticles.
Abstract: Composite absorbers based on conducting fabrics possessing moderate conductivity and dielectric/magnetic properties were prepared by in situ incorporation of nanoparticles of BaTiO3 (15–25 nm) or Fe3O4 (25–40 nm) within coated poly(aniline) (PANI) matrix. The X-ray diffraction patterns and transmission electron microscopy images confirmed the formation of PANI coating and incorporation of BaTiO3 or Fe3O4 nanoparticles. Scanning electron microscopy images show formation of thick and uniform coating of PANI over individual fibers and in interweave regions. The dielectric studies show that incorporation of BaTiO3 lead to enhancement of dielectric properties of PANI whereas magnetization measurements revealed that incorporation of Fe3O4 resulted in noticeable improvement in magnetic properties with saturation magnetization of 17.9 emu/g. The Ku-band (12.4–18.0 GHz) shielding studies revealed that pure PANI-coated fabric show total shielding effectiveness (SET) of −15.3 dB which enhanced to −16.8 and −19.4 dB ...
TL;DR: Coating copper nanowires to a ratio of 2:1 Cu:Ni gave them a neutral gray color, making them more suitable for use in displays and electrochromic windows, and make cupronickel nanoweires a promising alternative for the sustainable, efficient production of transparent conductors.
Abstract: Nanowires of copper can be coated from liquids to create flexible, transparent conducting films that can potentially replace the dominant transparent conductor, indium tin oxide, in displays, solar cells, organic light-emitting diodes, and electrochromic windows. One issue with these nanowire films is that copper is prone to oxidation. It was hypothesized that the resistance to oxidation could be improved by coating copper nanowires with nickel. This work demonstrates a method for synthesizing copper nanowires with nickel shells as well as the properties of cupronickel nanowires in transparent conducting films. Time- and temperature-dependent sheet resistance measurements indicate that the sheet resistance of copper and silver nanowire films will double after 3 and 36 months at room temperature, respectively. In contrast, the sheet resistance of cupronickel nanowires containing 20 mol % nickel will double in about 400 years. Coating copper nanowires to a ratio of 2:1 Cu:Ni gave them a neutral gray color, making them more suitable for use in displays and electrochromic windows. These properties, and the fact that copper and nickel are 1000 times more abundant than indium or silver, make cupronickel nanowires a promising alternative for the sustainable, efficient production of transparent conductors.
TL;DR: Transparent conductive carbon nanotube films were fabricated by dip-coating solutions of pristine CNTs dissolved in chlorosulfonic acid and then removing the CSA to preserve the length and quality and operate at high CNT concentration and coating speed without using surfactants.
Abstract: Transparent conductive carbon nanotube (CNT) films were fabricated by dip-coating solutions of pristine CNTs dissolved in chlorosulfonic acid (CSA) and then removing the CSA. The film performance and morphology (including alignment) were controlled by the CNT length, solution concentration, coating speed, and level of doping. Using long CNTs (∼10 μm), uniform films were produced with excellent optoelectrical performance (∼100 Ω/sq sheet resistance at ∼90% transmittance in the visible), in the range of applied interest for touch screens and flexible electronics. This technique has potential for commercialization because it preserves the length and quality of the CNTs (leading to enhanced film performance) and operates at high CNT concentration and coating speed without using surfactants (decreasing production costs).
TL;DR: Polymer coatings with the optimal polymer composition possessed significantly higher antifouling activity than PEG coating, and scanning electron microscopic studies showed that the polymer coating inhibited S. aureus biofilm formation over a period of 7 days.
TL;DR: These results demonstrate the first completely renewable intumescent LbL assembly, which conformally coats every fiber in cotton fabric and provides an effective alternative to current flame retardant treatments.
TL;DR: This coating realizes adequate photocatalytic activity for self-cleaning and inducing unique surface wettability changes, enabling energy-saving and maintenance-free characteristics.
Abstract: Superhydrophobic surfaces with photocatalytic self-cleaning properties are designed through coating a nanocomposite TiO(2) photocatalyst and hydrophobic polytetrafluoroethylene onto a structured substrate by applying a co-deposition technique. This coating realizes adequate photocatalytic activity for self-cleaning and inducing unique surface wettability changes. The nanocomposite can contain multiple functions, enabling energy-saving and maintenance-free characteristics.
TL;DR: A novel strategy is developed for the large-scale fabrication of reduced graphene oxide films directly on flexible substrates in a controlled manner by the combination of a rod-coating technique and room-temperature reduction of graphene oxide.
Abstract: A novel strategy is developed for the large-scale fabrication of reduced graphene oxide films directly on flexible substrates in a controlled manner by the combination of a rod-coating technique and room-temperature reduction of graphene oxide. The as-prepared films display excellent uniformity, good transparency and conductivity, and great flexibility in a touch screen.
TL;DR: In this article, the effect of cathode platinum loading on oxygen transport resistance in a fuel cell electrode was determined by measuring limiting current in fuel cells over a wide range of platinum loadings (0.03 to 0.40 mgPt/cm2).
Abstract: The effect of cathode platinum loading on oxygen transport resistance in a fuel cell electrode was determined by measuring limiting current in fuel cells over a wide range of platinum loadings (0.03 to 0.40 mgPt/cm2). The measurements show that the electrode oxygen transport resistance is inversely proportional to platinum loading or, equivalently, platinum surface area, and is mathematically similar to a 12 s/cm resistive film coating the active platinum sites. At low platinum loading this anomalous resistance significantly reduces the partial pressure of oxygen at the platinum surface and seriously degrades fuel cell performance at high power conditions. The magnitude of this film-like resistance is equivalent to ~35 nm of bulk-like ionomer but only 4–10 nm, assuming uniform coating, is present in the electrode. Alternatively, 380 nm diameter agglomerates with 20 nm of ionomer coating their external surface would create the same resistance, but such agglomerates are not apparent in SEM micrographs. As a result, the source of this resistance remains unknown, and further investigations are required to understand and mitigate it.
TL;DR: In this paper, an all-solution process that can be used to prepare transparent, stable and flexible VO2-based composite films is presented. But, the process is difficult to prepare in stable dispersive suspensions, and it may have applications for near infrared modulation of glass used in construction or cars.
Abstract: Vanadium dioxide is a key material for thermochromic smart windows that can respond to environmental temperature and modulate near infrared irradiation by changing from a transparent state at low temperature to a more reflective state at high temperature, while maintaining visible transmittance. VO2 thermochromism is commonly used in films on glass that function as smart windows. Flexible VO2 nanocomposite foils are able to combine the intrinsic properties of VO2 nanoparticles with the added functionalities contributed by nanoscale and interface effects, such as increased visible transparency and infrared modulation ability. These foils are promising for applications in construction and automotive glasses to increase energy efficiency. However, VO2 nanoparticles may be unstable, and they are difficult to prepare in stable dispersive suspensions. In this paper, we report a novel all-solution process that can be used to prepare transparent, stable and flexible VO2-based composite films. These films exhibit UV-shielding properties and an excellent temperature-responsive thermochromism in the near infrared region. A typical film has a solar modulation efficiency of 13.6%, which is the highest value for VO2 thermochromic films with comparable visible transmittance. Coating the VO2 nanoparticles with a thin SiO2 shell significantly improved their anti-oxidation and anti-acid abilities. This result represents an important breakthrough in VO2 thermochromism, and it may have applications for near infrared modulation of glass used in construction or cars.
TL;DR: In this paper, a conductive polymer surface coating on silicon nanowires (Si NWs) is used to improve the cycling stability of Li-ion battery anode material, which is attributed to the conductive coating maintaining the mechanical integrity of the cycled Si material, along with preserving electrical connections.
Abstract: For silicon nanowires (Si NWs) to be used as a successful high capacity lithium-ion battery anode material, improvements in cycling stability are required. Here we show that a conductive polymer surface coating on the Si NWs improves cycling stability; coating with PEDOT causes the capacity retention after 100 charge–discharge cycles to increase from 30% to 80% over bare NWs. The improvement in cycling stability is attributed to the conductive coating maintaining the mechanical integrity of the cycled Si material, along with preserving electrical connections between NWs that would otherwise have become electrically isolated during volume changes.
TL;DR: In this paper, four nitride coatings, TiN, TiAlN, AlTiN and CrAlN were deposited on YG6 (WC+6.% Co) cemented carbide by cathodic arc-evaporation technique.
Abstract: Four nitride coatings, TiN, TiAlN, AlTiN and CrAlN were deposited on YG6 (WC + 6 wt.% Co) cemented carbide by cathodic arc-evaporation technique. The friction and wear properties were investigated and compared using ball-on-disc method at high speed with SiC ball as a counter material. The tests were evaluated by scanning electron microscopy, X-ray diffractometer, energy dispersive X-ray, micro hardness tester and an optical profilometer. The results showed that TiN and TiAlN coatings presented lower friction coefficient and lower wear rate, and that high Al content AlTiN and CrAlN coatings didn't present better anti-wear properties in this test. Oxidation and abrasive wear were the main wear mechanism of TiN coating. In spite of the observation of micro-grooves and partial fractures, TiAlN possessed perfect tribological properties compared with the other coatings. High Al content increased the chemical reactivity and aroused severe adhesive wear of AlTiN coating. CrAlN coating presented better properties of anti-spalling and anti-adhesion, but abundant accumulated debris accelerated wear of the coating under this enclosed wear environment.
TL;DR: A novel TE concept based on the spin Seebeck effect, called 'spin-thermoelectric (STE) coating', which is characterized by a simple film structure, convenient scaling capability, and easy fabrication is shown, which may pave the way for novel applications making full use of omnipresent heat.
Abstract: Energy harvesting technologies, which generate electricity from environmental energy, have been attracting great interest because of their potential to power ubiquitously deployed sensor networks and mobile electronics. Of these technologies, thermoelectric (TE) conversion is a particularly promising candidate, because it can directly generate electricity from the thermal energy that is available in various places. Here we show a novel TE concept based on the spin Seebeck effect, called 'spin-thermoelectric (STE) coating', which is characterized by a simple film structure, convenient scaling capability, and easy fabrication. The STE coating, with a 60-nm-thick bismuth-substituted yttrium iron garnet (Bi:YIG) film, is applied by means of a highly efficient process on a non-magnetic substrate. Notably, spin-current-driven TE conversion is successfully demonstrated under a temperature gradient perpendicular to such an ultrathin STE-coating layer (amounting to only 0.01% of the total sample thickness). We also show that the STE coating is applicable even on glass surfaces with amorphous structures. Such a versatile implementation of the TE function may pave the way for novel applications making full use of omnipresent heat.
TL;DR: By coating cellulose and chitosan as well as the magnetic properties of Fe(3)O(4) to create a hybrid system to adsorb heavy metals, magnetic hybrid hydrogels with a novel polymeric coating were prepared.
TL;DR: In this paper, an approximately equimolar ratio TiVCrAlSi high entropy alloy coatings has been deposited by laser cladding on Ti-6Al-4V alloy.
TL;DR: In this article, a new hybrid nanostructure composed of three-dimensional ordered macroporous (3DOM) FeF3 and an homogenous coating of poly(3, 4-ethylenedioxythiophene) (PEDOT) is successfully synthesized using polystyrene (PS) colloidal crystals as hard template, and the coating of PEDOT is achieved through a novel in situ polymerization method.
Abstract: A new hybrid nanostructure composed of three-dimensionally ordered macroporous (3DOM) FeF3 and an homogenous coating of poly(3, 4-ethylenedioxythiophene) (PEDOT) is successfully synthesized using polystyrene (PS) colloidal crystals as hard template, and the coating of PEDOT is achieved through a novel in situ polymerization method. The special nanostructure provides a three-dimensional, continuous, and fast electronic and ionic path in the electrode. Surprisingly, the advantageous combination of 3DOM structure and homogenous coating of PEDOT endows the as-prepared hybrid nanostructures with a stable and high reversible discharge capacity up to 210 mA h g−1 above 2.0 V at room temperature (RT), and a good rate capability of 120 mA h g−1 at a high current density of 1 A g−1, which opens up new opportunities in the development of high performance next-generation lithium-ion batteries (LIBs).
TL;DR: Silicon core-hollow carbon shell nanocomposites with controllable voids between silicon nanoparticles and hollow carbon shell were easily synthesized by a two-step coating method and exhibited different charge-discharge cyclability as anodes for lithium-ion batteries.
Abstract: Silicon core-hollow carbon shell nanocomposites with controllable voids between silicon nanoparticles and hollow carbon shell were easily synthesized by a two-step coating method and exhibited different charge-discharge cyclability as anodes for lithium-ion batteries. The best capacity retention can be achieved with a void/Si volume ratio of approx. 3 due to its appropriate volume change tolerance and maintenance of good electrical contacts.
TL;DR: In this paper, a sulfur-polypyrrole composite cathode with a core-shell structure consisting of spherical sulfur particles coated with polypyroxide has been developed, which facilitates fast electron transport enabling the material with superior electrochemical stability, rate capability and cyclability in lithium-sulfur batteries.
Abstract: A sulfur-polypyrrole composite cathode with a core-shell structure consisting of spherical sulfur particles coated with polypyrrole has been developed. The conductive polypyrrole coating on the sulfur facilitates fast electron transport enabling the material with superior electrochemical stability, rate capability, and cyclability in lithium-sulfur batteries.
TL;DR: Thin carbonized polydopamine (C-PDA) coatings are found to have similar structures and electrical conductivities to those of multilayered graphene doped with heteroatoms.