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One of the key urban air quality issues is pollution by nitrogen oxides (NOx). To reduce NOx, facade cladding could be provided with photocatalytic properties by incorporating titanium dioxide nanoparticles. For this purpose, a modified phosphoric acid anodizing process (MPAA) was developed for the facade alloy EN AW-5005, in which highly ordered anodized structures with a low degree of arborization and tortuosity were produced. Pore widths between 70 nm and 150 nm and layer thicknesses of about 2–3 μm were obtained. The subsequent impregnation was carried out by dip coating from water-based systems. Depending on the dip-coating parameters and the suspension used, the pores can be filled up to 60% with the TiO2 nanoparticles. Photocatalytic tests according to ISO 22197-1 certify a high photocatalytic activity was obtained with rPCE values > 8 and with rPCE > 2, achieving “photocatalytically active for air purification”. Tests on the corrosion resistance of the anodized coatings with a commercially available aluminum and facade cleaner confirm a protective effect of the anodized coatings when compared with nonanodized aluminum material, as well as with compacted anodized layers.

Ordered assemblies of the peptide diphenylalanine (FF) are produced and deposited on planar substrates. The FF aggregate growth is achieved through precipitation from aqueous ammonia solutions induced by solvent evaporation. The applied dip-coating technique confines the FF assembly growth to a narrow zone near the three-phase contact. The growth was observed online by optical microscopy and was investigated systematically as a function of the process parameters. Depending on the external gas flow (to influence solvent evaporation), the withdrawal speed, the initial FF, and the initial ammonia concentrations, FF forms long, straight, and rigid microfibers and/or shorter, curved nanofibers. Under certain process conditions, the FF fibers can also aggregate into stripes. These can be deposited as large arrays of uniform stripes with regular widths and spacings. Scenarios leading to the various types of fibers and the stripe formation are presented and discussed in view of the experimental findings.

This research involves silica extraction from corn cob waste with the sol-gel method using qualitative and ashless filter paper as a comparison. Anti-reflective coatings, as silica thin films, were synthesized from the extracted silica using dip-coating and spin-coating methods. Extracted silicas were characterized with FTIR, XRF, and XRD, while thin films were characterized with UVVisible spectroscopy. The highest purity of extracted silica obtained was 66.5% using ashless filter paper. Silica thin films synthesized with spin-coating had a better refractive index compared to dipcoating, at 3.6.

This investigation is motivated by increasing interest in diamond and composite films for applications in biomedical and electronic devices. A biomimetic strategy is based on the use of commercial bile acids, such as ursodeoxycholic acid (UDCA) and hyodeoxycholic acid (HDCA). Composite films are developed using UDCA and HDCA as solubilizing agents for poly(ethyl methacrylate) (PEMA) in isopropanol and as dispersing agents for micro- and nanodiamonds. In this approach, the use of traditional toxic solvents for PEMA dissolution is avoided. The ability to obtain high concentrations of high molecular mass PEMA and disperse diamond particles in such solutions is a key factor for the development of a dip-coating method. The PEMA dissolution and diamond dispersion mechanisms are discussed. The composition and microstructure of the films can be varied by variation of the diamond particle size and concentration in the suspensions. The films can be obtained as singular layers of different compositions, multilayers of similar composition, or alternating layers of different compositions. The films combine corrosion protection property and biocompatibility of PEMA with advanced functional properties of diamonds.

Water/oil separation from their mixture and emulsion has been a prominent topic in fundamental research and in practical applications. In this work, a smart superhydrophobic membrane (SHP) was obtained by dipping an off-the-shelf laboratory filter paper in an ethanol suspension of trichloro (1H,1H,2H,2H-tridecafluoro-n-octyl) silane, tetraethyl orthosilicate, and titanium dioxide nanoparticles with different dimensions of 20 and 100 nm. The selection of membrane substrates was optimized including different quantitative and quantitative filter papers with different filtration velocity (slow, intermediate, and fast). The as-prepared SHP was demonstrated to be superhydrophobic and photosensitive, which was used in the separation of carbon tetrachloride and water from their mixture and emulsion. Moreover, orderly aligned micropores were formed for the modified superhydrophobic filter papers by using nanosecond laser. Unidirectional penetration was obtained for the UV-irradiated paper with a bored pore in the range of 50–500 μm in the systems of air/water and water/oil. This study may promote the understanding of unidirectional transportation of liquid droplet and facilitate the design of interfacial materials with Janus-type wettability.

Films formed by dip coating brass wires with dilute and semi-dilute solutions of polyvinyl butyral in benzyl alcohol were studied in their liquid and solid states. While dilute and semi-dilute solutions behaved as Maxwell viscoelastic fluids, the thickness of the liquid films followed the Landau-Levich-Derjaguin prediction for Newtonian fluids. At a very slow rate of coating, the film thickness was difficult to evaluate. Therefore, the dynamic contact angle was studied in detail. We discovered that polymer additives preserve the advancing contact angle at its static value while the receding contact angle follows the Cox–Voinov theory. In contrast, the thickness of solid films does not correlate with the Landau-Levich-Derjaguin predictions. Only solutions of high-molecular-weight polymers form smooth solid films. Solutions of low-molecular-weight polymers may form either solid films with an inhomogeneous roughness or solid polymer domains separated by the dry substrate. In technological applications, very dilute polymer solutions of high-molecular-weight polymers can be used to avoid inhomogeneities in solid films. These solutions form smooth solid films, and the film thickness can be controlled by the experimental coating conditions.

Bismuth compounds are of growing interest with regard to potential applications in catalysis, medicine and electronics, for which their environmentally benign nature is one of the key factors. The most common starting material is bismuth nitrate, which easily hydrolyses to give a large number of condensation products. The so-called bismuth subnitrates are composed of bismuth oxido clusters of varying composition and nuclearity. One reason that hampers the further development of bismuth oxido-based materials, however is the low solubility of the subnitrates, which makes targeted immobilisation on substrates challenging. We present an approach towards solubilisation of bismuth oxido clusters by introducing an amino carboxylate as functional group and a study of the growth mode of these atom-precise nanoclusters on gold surfaces. For this purpose the bismuth oxido cluster [Bi38O45(NO3)20(dmso)28](NO3)4*4dmso (dmso=dimethyl sulfoxide) was reacted with the sodium salt of tert-butyloxycabonyl(Boc)-protected phenylalanine (Phe) to give the soluble and chiral nanocluster [Bi38O45(Boc-Phe)24(dmso)9]. The hydrodynamic diameter of the cluster was estimated with (1.4-1.6) nm (in CH3CN) and (2.2 nm-2.9) nm (in Ethanol) based on dynamic light scattering (DLS). The full exchange of the nitrates by the amino carboxylates was proven by NMR and FTIR as well as elemental analysis (EA) and XPS. The solubility of the bismuth oxido cluster in a protic as well as an aprotic polar organic solvent and the growth mode of the clusters on Au upon spin-, dip-, and drop-coating on gold surfaces were studied. Successful deposition of bismuth oxido cluster was proven by powder XRD, FTIR, and XPS while the microstructure of the resulting films was investigated as a function of the deposition method and the solvent used by SEM, AFM, and optical microscopy.

Hydrophobic and oleophilic Si-based cotton fabrics have recently gained a lot of attention in oil/water separation due to their high efficiency. In this study, we present the effect of O2 plasma pre-treatment on the final properties of two Si-based cotton membranes obtained from dip coating and plasma polymerization, using polydimethylsiloxane (PDMS) as starting polymeric precursor. The structural characterizations indicate the presence of Si bond on both the modified cotton surfaces, with an increase of the carbon bond, assuring the success in surface modification. On the other hand, employing O2 plasma strongly changes the cotton morphology, inducing specific roughness and affecting the hydrophobicity durability and separation efficiency. In particular, the wettability has been retained after 20 laundry tests at 40 °C and 80 °C, and, for separation efficiency, even after 30 cycles, an improvement in the range of 10–15%, both at room temperature and at 90 °C can be observed. These results clearly demonstrate that O2 plasma pre-treatment, an eco-friendly, non-toxic, solvent-free, and one-step method for inducing specific functionalities on surfaces, is very effective in enhancing the oil/water separation properties for Si-based cotton membranes, especially in combination with plasma polymerization procedure for Si-based deposition.

The environmental impact of industrial technologies and related remediation methods are major research trend lines. Unfortunately, in the development of materials for wastewater treatment or air purification, hazardous reactants are often employed, reducing the overall beneficial contribution of such technology on the environment. We here synthesize stable titanium dioxide (TiO2) sols using a green route, with titanium tetraisopropoxide (TTIP) as precursor, water as solvent and acetic acid acting as catalyst, chelating agent and peptizing agent. The sol was deposited on glass by dip-coating and then analyzed using XRD, SEM and spectrophotometry. Wastewater purification ability was evaluated in the photocatalytic degradation of two organic dyes (Rhodamine B and Methylene Blue). Results on RhB showed > 85% degradation in 6 h maintained along a series of 7 tests, confirming good efficiency and reusability, and 100% in 3 h on MB; efficiency mostly depended on calcination temperature and layer thickness. High photodegradation efficiency was found in nonannealed samples, suggesting TiO2 nanoparticles crystallization during sol–gel production. Yet, such samples showed a gradual decrease in photoactivity in repeated tests, probably due to a partial release of TiO2 particles in solution, while on calcined samples a good adhesion was obtained, leading to a more durable photoactive layer.

Fuel electrode-supported tubular protonic ceramic cells (FETPCCs) based on the BaZr0.4Ce0.4Y0.15Zn0.05O3−δ (BZCYZ) membrane electrolyte was fabricated through a two-step method, in which the polyporous electrode-support tube was prepared with a traditional slip casting technique in a plaster mold, and the BZCYZ membrane was produced by a dip-coating process on the outside surface of the electrode-support tube. The dense thin-film electrolyte of BZCYZ with a thickness of ~25 μm was achieved by cofiring the fuel electrode support and electrolyte membrane at 1450 °C for 6 h. The electrochemical performances of the FETPCCs were tested under different solid oxide cell modes. In protonic ceramic fuel cell (PCFC) mode, the peak power densities of the cell reached 151–191 mW·cm−2 at 550–700 °C and exhibited relatively stable performance during continuous operation over 100 h at 650 °C. It was found that the major influence on the performance of tubular PCFC was the resistance and cathode current collectors. Additionally, in protonic ceramic electrolysis cell (PCEC) mode, the current densities of 418–654 mA·cm−2 were obtained at 600–700 °C with the applied voltage of 2.0 V when exposed to 20% CO2–80% H2 and 3% H2O/air. Using distribution of relaxation time analysis, the electrolytic rate-limiting step of the PCEC model was determined as the adsorption and dissociation of the gas on the electrode surface.

Recently, graphene and its derivatives have been of particular interest as a solid lubricant to reduce friction. The aim of this study was to investigate the morphology and structure of low-friction Al2O3 coatings containing reduced graphene oxide (rGO). Using two types of rGO, alumina coatings were produced by the sol–gel dip-coating method and characterized in terms of morphology and structure using SEM and AFM microscopy and Raman spectroscopy. It was found that composite Al2O3 + rGO coatings had diversified morphology depending on the type of graphene used. The dip-coating method used for deposition had a large impact on the morphology and contributed to the orderly arrangement of rGO nanoplates in the coating matrices. It was also shown that there is a correlation between the shape and spatial orientation of nanoplates and the tribological properties of coatings. The structural studies showed differences in the number of graphene defects in the coatings, which may indicate the chemical bonding of graphene with the alumina matrices. These differences may also be responsible for divergences in the tribological properties of the coatings depending on the type of graphene. All our findings indicate the key role of an appropriate balance between the parameters of composite coating production in terms of the desired tribological properties.

In this research, three different sets of hematite (α-Fe2O3) films of various thicknesses were prepared using dip, spin, and combined dip/spin coating methods. α-Fe2O3 films of 450–500, 740–800 and 920–980 ± 30 nm thicknesses were prepared using each of the coating methods, and their photoelectrochemical (PEC) behaviour was investigated. Dip coated films produced the best photoresponse while the films prepared using the spin coating method yielded the least photocurrent values across films of different thicknesses. Maximum photocurrent densities of 34.6, 7.8, and 13.5 μA/cm2 V vs reversible hydrogen electrode (RHE) were obtained for the dip, spin and combined dip/spin coated films with a thickness of 740–800 ± 30 nm respectively. Improved crystallization, low charge transfer resistance at the α-Fe2O3/electrolyte interface, high surface states capacitance and the more negative flat band potential values obtained for dip coated films have been associated with the enhanced photocurrent response recorded for the films. The preferential crystal growth of spin coated films in the (104) plane associated with low electron mobility and the high resistance to charge transfer at the α-Fe2O3/electrolyte interface of the films is largely responsible for their low photoresponse. This study underscores the significance of simultaneously optimizing both coating techniques for film deposition and the film’s thickness in preparing nanostructured α-Fe2O3 films for PEC applications.

In the present study, a dual composite coating consisted of an anodized layer as the inner layer and PCLF (polycaprolactone fumarate)/siliconand magnesium-codoped fluorapatite (Si-Mg-FA) nanocomposite as the outer layer was fabricated on AZ31 Mg alloy. The thickness of the PCLF/(Si-Mg-FA) nanocomposite coating is 9.72 μm, with the Si-Mg-FA nanoparticles being well distributed in the PCLF matrix. Electrochemical measurements showed that AZ31 with the anodized PCLF/Si-Mg-FA coating has a low corrosion current density (5.137 × 10–6 A/cm2), providing a sufficient protection (Rp = 5888.72 Ω cm2) for Mg alloys. Immersion tests in a simulated body fluid showed that cauliflower-like/cloudy apatite forms on AZ31 with the anodized PCLF/Si-Mg-FA coating and governs good bioactivity. Osteosarcoma cells adhere well to the surface of the coating. Surface modification by the anodized PCLF/Si-Mg-FA coating can be a suitable method for controlling the corrosion degradation and increasing the bioactivity and cell attachment of AZ31 Mg alloy for implant applications., В данной работе изготовлено двухслойное композитное покрытие на подложке из магниевого сплава AZ31. Покрытие состоит из внутреннего анодированного слоя и внешнего нанокомпозитного слоя из поликапролактона фумарата (ПКЛФ) и фторапатита (ФА), легированного кремнием и магнием (Si-Mg-ФА). Толщина нанокомпозитного ПКЛФ/Si-Mg-ФА покрытия составляет 9.72 мкм, при этом наночастицы Si-Mg-ФА равномерно распределены в матрице из ПКЛФ. Электрохимические измерения показали, что сплав AZ31 с анодированным ПКЛФ/Si-Mg-ФА покрытием имеет низкую плотность тока коррозии (5.137 × 10–6 А/см2) и достаточную коррозионную стойкость (Rp = 5888.72 Ом см2). Испытания в искусственной биологической жидкости показали, что на сплаве AZ31 с анодированным ПКЛФ/Si-Mg-ФА покрытием образуется пористый апатит, обеспечивающий хорошую биоактивность. Полученное покрытие способствует адгезии клеток остеосаркомы. Модификация поверхности сплава AZ31 анодированным ПКЛФ/Si-Mg-ФА покрытием может быть подходящим методом контроля коррозионного разрушения, увеличения биоактивности и прикрепления клеток, что позволяет использовать сплав AZ31 в имплантологии.

The development of antimicrobial polymers is a priority for engineers fighting microbial resistant strains. Silver ions and silver nanoparticles can assist in enhancing the antimicrobial properties of microcapsules that release such substances in time which prolongs the efficiency of antimicrobial effects. Therefore, this study aimed to functionalize different polymer surfaces with antimicrobial core/shell microcapsules. Microcapsules were made of sodium alginate in shell and filled with antimicrobial silver in their core prior to application on the surface of polymer materials by dip-coating methodology. Characterization of polymers after functionalization was performed by several spectroscopic and microscopic techniques. After the characterization of polymers before and after the functionalization, the release of the active substances was monitored in time. The obtained test results can help with the calculation on the minimal concentration of antimicrobial silver that is encapsulated to achieve the desired amounts of release over time.

Improved corrosion protection of low-carbon steel was achieved by barrier non-toxic sol–gel multilayered structures composed of a ZrO2 top coating and TiO2 underlayers. The zirconium precursor solution was maintained as constant, whereas the TiO2 solution composition was modified with two different types of polymers, which were added separately to the starting titanium solution. The phase composition, morphology and corrosion protective properties were analyzed by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Hydrophobicity properties were evaluated by measuring the contact angle with a Ramé-Hart automated goniometer. The potentiodynamic polarization technique was used to determine the corrosion resistance and protective ability of the coatings in a 5% NaCl solution. Both polymeric modifications, as compared to the non-modified titania layer, demonstrated positive effects on the corrosion properties of the structures at conditions of external polarization. Due to the amorphous structure of the zirconia layer and its relatively dense, hydrophobic surface, all of the samples extended the service life of low-carbon steel in a model corrosion medium. The feasibility of the sol–gel deposition method makes it possible to prepare oxide coatings with appropriate surface properties, which ensures high corrosion resistance.

Tubular oxygen transport membranes (OTMs) that can be directly integrated in high temperature processes have a large potential to reduce CO2 emissions. However, the challenging processing of these multilayered tubes, combined with strict material stability requirements, has so far hindered such a direct integration. We have investigated if a porous support based on (Y2O3)0.03(ZrO2)0.97 (3YSZ) with a dense composite oxygen membrane consisting of (Y2O3)0.01(Sc2O3)0.10(ZrO2)0.89 (10Sc1YSZ) as an ionic conductor and LaCr0.85Cu0.10Ni0.05O3&minus, &delta, (LCCN) as an electronic conductor could be fabricated as a tubular component, since these materials would provide outstanding chemical and mechanical stability. Tubular components were made by extrusion, dip coating, and co-sintering, and their chemical and mechanical integrity was evaluated. Sufficient gas permeability (&ge, 10&minus, 14 m2) and mechanical strength (&ge, 50 MPa) were achieved with extruded 3YSZ porous support tubes. The high co-sintering temperature required to densify the 10ScYSZ/LCCN membrane on the porous support, however, causes challenges related to the evaporation of chromium from the membrane. This chemical degradation caused loss of the LCCN electronic conducting phase and the formation of secondary lanthanum zirconate compounds and fractures. LCCN is therefore not suitable as the electronic conductor in a tubular OTM, unless means to lower the sintering temperature and reduce the chromium evaporation are found that are applicable to the large-scale fabrication of tubular components.

ZnO-CuO flower-like hetero-nanostructures were successfully prepared by combining hydrothermal and dip coating methods. Flower-like hetero-nanostructures of ZnO-CuO were examined by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and UV-Vis. The sensing properties of ZnO-CuO flower-like hetero-nanostructures to volatile organic compounds (VOCs) were evaluated in a chamber containing acetone or isopropanol gas at room temperature. The sensitivity of ZnO-CuO flower-like hetero-nanostructures to VOCs was enhanced compared to that of pure leafage-like ZnO nanostructures. Response and recovery times were about 5 s and 6 s to 50 ppm acetone, and 10 s and 8 s to 50 ppm isopropanol, respectively. The sensing performance of ZnO-CuO flower-like hetero-nanostructures was attributed to the addition of CuO that led to formation of p-n junctions at the interface between the CuO and ZnO. In addition, the sensing mechanism was briefly discussed.

International audience; Niobium pentoxide, Nb2O5, exists in many polymorphs with diverse properties and morphologies that are dependent on the synthesis route. In this work, we design a new approach to fabricate and stabilize the metastable polymorph hexagonal nano-niobium pentoxide using soft chemistry and in particular the polyol synthesis. The electrochromic properties of homogeneous niobium pentoxide thin films deposited by dip coating, from as-synthesized hexagonal powder, are studied in lithium trifluoromethanesulfonimide (LiTFSI) in 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMITFSI) ionic liquid electrolyte versus Pt as counter electrode. The structure and morphology of the Nb2O5 thin films before and after cycling are characterized by ex-situ XRD and SEM while their optical and electrochemical properties are investigated by in-situ transmittance and cyclic voltammetry (CV), respectively. Thin films made from hexagonal Nb2O5 with a sphere architecture exhibit good cycling stability, high transmittance modulations (ΔT ≈ 33% at 550 nm), fast switching speeds (2–3 s for coloration and bleaching at 550 nm), and high coloration efficiency (CE ≈ 26 cm2 C–1) with a good quality factor G(λ) = 10.4 cm2 C–1 s–1. Finally, novel electrochromic devices based on hybrid thin films combining poly(ethylene-3,4-dioxythiophene):poly(styrenesulfonicacid) (PEDOT:PSS) and oxides are assembled showing enhanced coloration and simultaneous color change due to their double-sided configuration.

Al-Zn doped SnO2 (Sn1-2xAlxZnxO2) film has been growth using the sol-gel dip coating technique. The basic materials used in this study were water, C2H5OH, SnCl2.2H2O, AlCl3 and ZnCl2 with 99% purity (merck) with doping concentration variation x = 0.000, 0.005, 0.025, and 0.050. Glass substrate with size 2.54 mm x 76.2 mm x 1 mm cleaned with detergent, soaked in 30% HCl solution For 1 day and dried at 100°C. The process of making a SnO2 sol is done by mixing the precursor with various concentrations with water and stirring using a magnetic stirrer for 30 minutes at a temperature of 80 ° C. The next step by adding ethanol, stirring at 80 ° C. for 2 hours to obtain 0.4 M sol solution The deposition of SnO2 film was carried out using a dip coater with a whitdrawl speed 12 cm/min and then heated for nucleation and grown using an electric furnace at 600 ° C for 30 minutes. This step is repeated as much as 5 repetitions to get the SnO2 film by doing Al-Zn.

CuAlS 2 thin films were deposited by a dip coating technique at room temperature. The X-ray energy dispersive (EDAX) and X-ray diffraction (XRD) analysis showed that the deposited CuAlS 2 thin film is nearly stoichiometric and possesses a tetragonal unit cell structure. The crystallite sizes determined from the XRD data employing Scherrer's formula and modified forms of Hall–Williamson relation like the uniform deformation model (UDM), uniform stress deformation model (USDM), uniform deformation energy density model (UDEDM), and the size–strain plot method (SSP) were in good agreement with each other. The transmission electron microscopy (TEM) and scanning electron microscopy (SEM) studies of the thin film revealed that the deposited film is uniform without any cracks and the film covers the whole of the substrates. The atomic force microscopy (AFM) of the as-synthesized thin film surfaces showed spherical grains having coalescences between them. The optical absorbance spectrum analysis showed that the thin films possess both direct and indirect band gaps. The semiconducting and p -type nature of the thin films was confirmed from dc – electrical resistivity versus temperature, room temperature Hall effect, and Seebeck coefficient versus temperature measurements. The effect of the different illuminations on the CuAlS 2 thin film showed that it can be used as a material for absorption of ultra-violet radiation. All the obtained characterization results are deliberated in detail.

Uniform and pinhole-free electron-selective TiO2 layers are of utmost importance for efficient perovskite solar cells. Here we used a scalable and low-cost dip-coating method to prepare uniform and ultrathin (5–50 nm) compact TiO2 films on fluorine-doped tin oxide (FTO) glass substrates. The thickness of the film was tuned by changing the TiCl4 precursor concentration. The formed TiO2 follows the texture of the underlying FTO substrates, but at higher TiCl4 concentrations, the surface roughness is substantially decreased. This change occurs at a film thickness close to 20–30 nm. A similar TiCl4 concentration is needed to produce crystalline TiO2 films. Furthermore, below this film thickness, the underlying FTO might be exposed resulting in pinholes in the compact TiO2 layer. When integrated into mesoscopic perovskite solar cells there appears to be a similar critical compact TiO2 layer thickness above which the devices perform more optimally. The power conversion efficiency was improved by more than 50% (...

For the preparation of electrically conductive composites, various combinations of cellulose and conducting materials such as polymers, metals, metal oxides and carbon have been reported. The conductivity of these cellulose composites reported to date ranges from 10−6 to 103 S cm−1. Cellulose nanocrystals (CNCs) are excellent building blocks for the production of high added value coatings. The essential process steps for preparing such coatings, i.e. surface modification of CNCs dispersed in water and/or alcohol followed by application of the dispersion to substrate samples using dip coating, are low cost and easily scalable. Here, we present coatings consisting of Ag modified CNCs that form a percolated network upon solvent evaporation. After photonic sintering, the resulting coatings are electrically conductive with an unprecedented high conductivity of 2.9 × 104 S cm−1. Furthermore, we report the first colloidal synthesis that yields CNCs with a high degree of Ag coverage on the surface, which is a prerequisite for obtaining coatings with high electrical conductivity.

The recently introduced perovskite solar cell (PSC) technology is a promising candidate for providing low-cost energy for future demands. However, one major concern with the technology can be traced back to morphological defects in the electron selective layer (ESL), which deteriorates the solar cell performance. Pinholes in the ESL may lead to an increased surface recombination rate for holes, if the perovskite absorber layer is in contact with the fluorine-doped tin oxide (FTO) substrate via the pinholes. In this work, we used sol-gel-derived mesoporous TiO2 thin films prepared by block co-polymer templating in combination with dip coating as a model system for investigating the effect of ESL pinholes on the photovoltaic performance of planar heterojunction PSCs. We studied TiO2 films with different porosities and film thicknesses, and observed that the induced pinholes only had a minor impact on the device performance. This suggests that having narrow pinholes with a diameter of about 10 nm in the ESL is in fact not detrimental for the device performance and can even, to some extent improve their performance. A probable reason for this is that the narrow pores in the ordered structure do not allow the perovskite crystals to form interconnected pathways to the underlying FTO substrate. However, for ultrathin (~20 nm) porous layers, an incomplete ESL surface coverage of the FTO layer will further deteriorate the device performance.

The sensitivity of Fiber Bragg Gratings (FBGs) to the variation of a specific parameter can be improved by choosing a suitable coating material. This paper explores the possibility of measuring the concentration of Ethanol in aqueous solutions by using poly (methyl methacrylate) (PMMA) as coating material of a single-mode FBG. The basic measurement principle relies in the absorption of liquid Ethanol which produces controlled swallowing of the coating, straining the underneath Bragg grating. The PMMA coating was deposited on the FBG by means of a specifically designed dip coating test bench, able to accurately control the thickness of the applied layer. Metrological performances of the developed PMMA-coated FBG Ethanol sensor have been assessed for Ethanol concentrations in the range of 0-38 % in distilled water at 25 °C constant temperature. The prototype shows good repeatability and better sensitivity when compared to an uncoated FBG, especially at low Ethanol concentrations. The dynamic behavior of the sensor (which depends on the kinetics of the absorption mechanism) has been assessed as well, showing a response time of about 290 s, while the recovery time (660 s) was almost twice.

Industrial dip coating is a simple and easy to access technique that can be considered as a self-metered coating process. Practical applications of films obtained by this method include decorative, protective, and functional purposes. The objective of this work was to develop a 2D mathematical model of the fluid-dynamic variables of the dip-coating draining stage of a finite vertical plate, considering nonevaporative and isothermal conditions. Concentrated dispersions were considered, such as those whose rheological behavior was described by an extension of a theoretical rheological model proposed by Quemada. As a result, an analytical and simple mathematical model that relates the main fluid parameters could be obtained. The model was achieved based upon rigorous mass and momentum balances applied to the draining stage of a monophasic, isothermal, and nonevaporative system, where the highest forces are viscous and gravitational. Parameters that were estimated are the velocity profile, average velocity, flow rate, local thickness, and average thickness of the film. Finally, experimental validation was performed by using experimental data (rheological properties, densities, and average film thickness values) of several representative concentrated dispersions (emulsions and suspensions) obtained in this work and from the literature. All the information achieved in this study can be useful to control and predict the thickness and homogeneity of the film during an industrial coating process, in order to satisfy the quality requirements of the final product. Fil: Peralta, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Meza, Barbara Erica del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina

Surface modification is one of the methods for improving the performance of medical implants in biological environment. In this study, cerium, gallium and zinc substituted 80%SiO 2 -15%CaO-5%P 2 O 5 mesoporous bioactive glass (MBG) in combination with polycaprolactone (PCL) were coated over Ti6Al4 V substrates by dip-coating method in order to obtain an inorganic—organic hybrid coating (MBG-PCL). Structural characterization was performed using XRD, nitrogen adsorption, SEM-EDXS, FTIR. The MBG-PCL coating uniformly covered the substrate with the thickness found to be more than 1 μm. Glass and polymer phases were detected in the coating along with the presence of biologically potent elements cerium, gallium and zinc. In addition, in vitro bioactivity was investigated by soaking the coated samples in simulated body fluid (SBF) for up to 30 days at 37 °C. The apatite-like layer was monitored by FTIR, SEM-EDXS and ICP measurements and it formed in all the samples within 15 days except zinc samples. In this way, an attempt was made to develop a new biomaterial with improved in vitro bioactive response due to bioactive glass coating and good mechanical strength of Ti6Al4 V alloy along with inherent biological properties of cerium, gallium and zinc.

We numerically analyze the process of dip coating on fibers when the liquid to be deposited contains soluble surfactants. The predictions obtained are in excellent agreement with experimental results reported by different authors. Our results show that the thickness of the film deposited, and particularly the so-called surfactant thickening effect, changes its behavior when the coating speed exceeds certain limits; therefore, the effects produced by inertia forces are scrutinized to uncover, for the first time, the mechanisms inducing those changes. Fil: Campana, Diego Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Ubal, Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Giavedoni, Maria Delia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Saita, Fernando Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina

Made available in DSpace on 2018-12-11T16:41:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-04-06 A reliable and cheap equipment is hereby proposed for the deposition of thin films on several substrates. This system is capable of deposition using three different techniques sequentially on the same substrate. The techniques available are ionic layer adsorption and reaction (SILAR), electrodeposition, and dip coating on both rigid and flexible conductive substrates (FTO, ITO-PEN). Using low-cost electronic components, we built a working prototype, driven by a simple software that is open source and user-friendly. In order to test our system, we used it to fabricate dye-sensitized solar cells (DSSCs) and counter electrodes of platinum and cobalt sulfide using both rigid glass-FTO and flexible ITO-PEN substrates. The electrodes as well as the complete devices have been characterized through cyclic voltammetry (CV). The solar cell devices have been characterized through current versus voltage curves (I-V) under simulated solar illumination. Programa de Pós-Graduação em Ciência e Tecnologia de Materiais (POSMAT) Universidade Estadual Paulista (UNESP), Av. Eng. Luiz Edmundo Carrijo Coube14-01 Department of Chemistry University of Rome “La Sapienza”, Piazzale Aldo Moro 5 Universidade Estadual Paulista UNESP, Av. Eng. Luiz Edmundo Carrijo Coube14-01 Programa de Pós-Graduação em Ciência e Tecnologia de Materiais (POSMAT) Universidade Estadual Paulista (UNESP), Av. Eng. Luiz Edmundo Carrijo Coube14-01 Universidade Estadual Paulista UNESP, Av. Eng. Luiz Edmundo Carrijo Coube14-01

Absorbable magnesium stents have become alternatives for treating restenosis owing to their better mechanical properties than those of bioabsorbable polymer stents. However, without modification, magnesium alloys cannot provide the proper degradation rate required to match the vascular reform speed. Gallic acid is a phenolic acid with attractive biological functions, including anti-inflammation, promotion of endothelial cell proliferation, and inhibition of smooth muscle cell growth. Thus, in the present work, a small-molecule eluting coating is designed using a sandwich-like configuration with a gallic acid layer enclosed between poly (d,l-lactide-co-glycolide) layers. This coating was deposited on ZK60 substrate, a magnesium alloy that is used to fabricate bioresorbable coronary artery stents. Electrochemical analysis showed that the corrosion rate of the specimen was ~2000 times lower than that of the bare counterpart. The released gallic acid molecules from sandwich coating inhibit oxidation by capturing free radicals, selectively promote the proliferation of endothelial cells, and inhibit smooth muscle cell growth. In a cell migration assay, sandwich coating delayed wound closure in smooth muscle cells. The sandwich coating not only improved the corrosion resistance but also promoted endothelialization, and it thus has great potential for the development of functional vascular stents that prevent late-stent restenosis.

A microwave deposition technique for silanes, previously described for production of oleophobic fabrics, is adapted to provide a fabric support material that can be subsequently treated by dip coating. Dip coating with a sol preparation provides a supported porous layer on the fabric. In this case, the porous layer is a porphyrin functionalized sorbent system based on a powdered material that has been demonstrated previously for the capture and conversion of phosgene. A representative coating is applied to cotton fabric at a loading level of 10 mg/g. This coating has minimal impact on water vapor transport through the fabric (93% of the support fabric rate) while significantly reducing transport of 2-chloroethyl ethyl sulfide (CEES) through the material (7% of support fabric rate). The described approaches are suitable for use with other fabrics providing amine and hydroxyl groups for modification and can be used in combination with other sol preparations to produce varying functionality.

The symposium ISPDS2 has taken place in Meknes (Morocco) in October, 2017. It has gathered specialists of various fields who presented their work in connection with the problematics of data storage. This conference volume contains 75 abstracts of communications presented at the meeting as invited conferences, talks, or posters. Various topics are covered, as carbon nanotubes, SWCN, Domain walls, piezoelectrics, anomalous diffusion, electron microscopy, spectral moments, SiGe, nanocrystals, magneto-caloric, electro-caloric, ferrite, spinels, perovskites, graphene, solar cells, colossal magnetoresistance (CMR)

Both polypyrrole (PPy) and polypyrrole coated copper thin films were synthesized successfully via two-step methods. PPy nanorods films were first grown chemically, and then PPy thin films were fabricated on glass substrates using dip-coating technique. The resulting films were examined via various characterization methods such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and Thermal Gravimetric Analysis (TGA). Gas sensor devices were fabricated and the gas sensitivity for (PPy) coated copper was measured as a function of temperature for both O2 and CO2 gases. The maximum sensitivity for O2 gas was around 160% and the maximum sensitivity for CO2 was 300%. Keywords: Polypyrrole coated copper, Gas sensor, Nanowires, Thin film, Dip coating

A method to enhance the adherence of Al 2 O 3 coating with AISI 316L metallic substrate was proposed in this study. The substrate was aluminized by pack cementation at 850°C for 10 h, and then oxidized at 900°C for 10 h, subsequently, the Al 2 O 3 whiskers formed uniformly. The suspension mixing 3 μm γ-Al 2 O 3 powder, alumina sol, PVA and water was directly applied to the microchannels pretreated by above mentioned aluminizing and oxidation method by dip coating. And then the sample was dried and calcined at 600°C for 2 h to form γ-Al 2 O 3 coating in the micochannel. The morphology and phase composition of the coating were characterized by X-Ray diffraction (XRD), energy dispersive spectrometer (EDS), scanning electron microscope (SEM). The adhesion between the substrate and coating was tested by ultrasonic vibration. The results showed that aluminized treatment could effectively improve the adhesion, and the mass-loss rate of the coating was only 1.24%. The main pore size of the coating was between 30 A and 100 A. The coating has no cracks, and possessed with high specific surface area, 234 m 2 /g.

This paper reports the influence of annealing temperature on crystalline size, film roughness, surface morphology and photoluminescence properties of ZnO thin films prepared by dip and spin coating techniques. Thin films were annealed at 400 °C and 500 °C for one hour each and their structural properties were studied using XRD, AFM and SEM. The coatings were characterized for photoluminescence using UV-visible Spectrometer. The films produced by both the methods conformed to hexagonal wurtzite structure. The grain size of dip coated films annealed at 400 °C and 500 °C were 291 and 312 nm and for spin coated films were 140 nm and 172 nm respectively. The surface roughness values of the dip coated films corresponding to the two temperatures were 17.31 nm and 23.52 nm and those for spin coated films were 16.74 and 21.43 nm respectively. Annealing temperature significantly influenced crystallinity and surface roughness of the thin films in both methods of coating.

In this work, we analyze the efficiency of the modification of the implant surface. This modification was reached by the formation of a two-level relief hierarchy by means of a sol-gel approach that included dip coating with subsequent shock drying. Using this method, we fabricated a nanoporous layer with micron-sized defects on the nanotitanium surface. The present work continues an earlier study by our group, wherein the effect of osteoblast-like cell adhesion acceleration was found. In the present paper, we give the results of more detailed evaluation of coating efficiency. Specifically, cytological analysis was performed that included the study of the marker levels of osteoblast-like cell differentiation. We found a significant increase in the activity of alkaline phosphatase at the initial incubation stage. This is very important for implantation, since such an effect assists the decrease in the induction time of implant engraftment. Moreover, osteopontin expression remains high for long expositions. This indicates a prolonged osteogenic effect in the coating. The results suggest the acceleration of the pre-implant area mineralization and, correspondingly, the potential use of the developed coatings for bone implantation.

[EN] In this research, Cu-doped TiO2 thin films have been successfully deposited onto a glass substrate by Sol¿gel technique using dip coating method. The films were annealed at different annealing temperatures (400¿500 "C) for 1 h. The structural, optical and electrical properties of the films were investigated and compared using X-ray Diffraction,UV¿visible spectrophotometer and 4-point probe method. Optical analysis by mean transmittance T(k) and absorption A(k) measurements in the wavelength range between 300 to 800 nm allow us to determine the indirect band gap energy. DRX analysis of our thin films of TiO2:Cu shows that the intensities of the line characteristic of anatase phase increasing in function of the temperature., This work has been partially supported by LGOPS Laboratory University Polytechnic University of Valencia, Spain and LMOPS Laboratory University of Lorraine France. Technical support from LMOPS and LGOPS labs is gratefully acknowledged.

Graphical abstract, Recent advances in the use of plasmonic metamaterials to improve absorption of light in thin-film solar photovoltaic devices has created a demand for a scalable method of patterning large areas with metal nanostructures deposited in an ordered array. This article describes two methods of fabricating ordered 2D nanosphere colloidal films: spin coating and interface coating. The two methods are compared and parameter optimization discussed. The study reveals that: • For smaller nanosphere sizes, spin coating is more favorable, while for larger nanospheres, the angled interface coating provides more coverage and uniformity. • A surfactant-free approach for interface coating is developed to fabricate zero-contamination colloidal films. • Each of the methods reaches an overall coverage of more than 90% and can be used for nanosphere lithography to form plasmonic metamaterials.

Fluorapatite (FA) layers with different thickness and microstructures on porous 3 mol% yttria-partially stabilized zirconia (Y-PSZ) substrates have been fabricated by dipping porous zirconia tapes into aqueous fluorapatite slurries. Porous ZrO2 tapes were developed using starch and an acrylic latex as fugitive additive and binder, respectively. Two different binders, poly(vinyl)alcohol (PVA) and latex were used to prepare the fluorapatite dip coating slips. The influence of the suspension properties and the porous structure of the tape surfaces (top and bottom) on the formation rate and consequently on the layer thickness formed on each surface were studied. In addition, the microstructure of the layers produced by using the different dip-coating slips were compared and the osteoblastic cellular response to the different FA coating layers was examined. A greater initial thickness of the layer adhered was found for the tapes dip coated in the FA slip with latex; for immersion times>0, the casting rate was observed to be strongly influenced by both the structure of the tape surfaces and the suspension properties. For both FA slurries, the casting rate at the top surface of the tapes was greater than that at the bottom surface. Sintered layers with thickness 8–9 times greater on both tape surfaces were found using the dip coating slip with latex. For each tape surface, the casting rate was accelerated and the layer shrink during sintering was reduced by using the dip coating slip with latex. The coating layer produced with latex enhanced the osteogenic potential of osteoblastic cells in vitro, which is ultimately an indication of the material׳s capacity to promote bone repair in vivo. Fil: Albano, Maria Patricia. Provincia de Buenos Aires. Gobernación. Comision de Invest.científicas. Centro de Tecnología de Recursos Minerales y Ceramica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Tecnología de Recursos Minerales y Ceramica; Argentina Fil: Garrido, Liliana Beatriz. Provincia de Buenos Aires. Gobernación. Comision de Invest.científicas. Centro de Tecnología de Recursos Minerales y Ceramica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Tecnología de Recursos Minerales y Ceramica; Argentina Fil: Teixeira, Lucas Novaes. Universidade de Sao Paulo; Brasil Fil: Rosa, Adalberto Luiz. Universidade de Sao Paulo; Brasil Fil: Tambasco de Oliveira, Paulo. Universidade de Sao Paulo; Brasil

Thin fluorapatite (FA) layers on porous 3 mol% yttria-partially stabilized zirconia (Y-PSZ) substrates have been fabricated by dipping porous zirconia tapes into aqueous 27.4 vol% fluorapatite slurries. Two porous Y-PSZ tapes with different volume fraction of porosity were developed using an acrylic latex binder: tapes with 31.4 vol% porosity were prepared using 16.6 vol% starch as fugitive additive and those with 12.7 vol% porosity were fabricated without starch. The influence of the porous structure of the tape surfaces, top and bottom, on the casting rate and consequently on the layer thickness formed on each surface was studied. Layers formed on the top and bottom surfaces of the tapes with 12.7 and 31.4 vol% porosity were compared. The formation of a thin layer on the surface of the tape was governed by both liquid entrainment and slip casting mechanisms. The data for the FA layer formation were in good agreement with the slip casting model for immersion times>0. The casting rate at the top surface of both tapes was greater than that at the bottom surface. This difference was attributed to a greater porosity of the top surface with respect to that of the bottom one and was more pronounced for the tapes prepared with starch. Layers formed on the top surface were found to be about 55 and 32% thicker than those formed on the bottom surface for the tapes fabricated with and without starch, respectively. For the tapes prepared with starch, the greater porosity and number of smaller pores in the matrix of the top surface increased the casting rate and produced the thickest dip coated layers. Fil: Albano, Maria Patricia. Provincia de Buenos Aires. Gobernación. Comision de Invest.científicas. Centro de Tecnología de Recursos Minerales y Ceramica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Tecnología de Recursos Minerales y Ceramica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Garrido, Liliana Beatriz. Provincia de Buenos Aires. Gobernación. Comision de Invest.científicas. Centro de Tecnología de Recursos Minerales y Ceramica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Tecnología de Recursos Minerales y Ceramica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

TFA-MOD (Metal Organic Deposition using Trifluoro-acetates) process is of considerable practical concern for future applications since it can fabricate high performance coated conductors (CCs) with low cost. In this study, we developed the process for fabricating thick films in BZO nanoparticle doped Y 0.77 Gd 0.23 Ba 1.5 Cu 3 O y (YGdBCO) CCs in order to realize high I c values under magnetic field. The effect of RTR (Reel To Reel)-dip-coating conditions on microstructure, J c(- B -θ) properties, etc. was investigated in order to fabricate crack-free thick and high performance films. A BZO doped YGdBCO film with uniform 3.0 μm thickness showed the high in-field I c and J c values of 55.6 A/cm-w and 0.18 MA/cm 2 @77.8K, 3T, respectively.

Joint replacement is being actively developed within modern orthopedics. One novel material providing fast implantation is bioactive coatings. The synthesis of targeted nanocoatings on metallic nanotitanium surface is reported in this paper. TiO2-based micro- and nanocoatings were produced by sol-gel synthesis using dip-coating technology with subsequent fast (shock) drying in hot plate mode at 400 °C. As a result of shock drying, the two-level hierarchical TiO2 nanolayer on the nanotitanium was obtained. This two-level hierarchy includes nanorelief of porous xerogel and microrelief of the micron-sized “defect” network (a crack network). The thickness of TiO2 nanolayers was controlled by repeating dip-coating process the necessary number of times after the first layer deposition. The state of the MS3T3-E1 osteoblast cell line (young cells that form bone tissue) on the two-level hierarchical surface has been studied. Particularly, adhesion character, adhesion time and morphology have been studied. The reported results may serve the starting point for the development of novel bioactive coatings for bone and teeth implants.

Azamsadat Madani,1 Mohammadreza Nakhaei,2 Parisa Karami,3 Ghadir Rajabzadeh,4 Sahar Salehi,4,5 Hossein Bagheri6 1Dental Research Center, Department of Prosthodontics, Faculty of Dentistry, Mashhad University ofMedical Sciences, 2Dental Materials Research Center, Department of Prosthodontics, Faculty of Dentistry, Mashhad University of Medical Sciences, Mashhad, 3Department ofProsthodontics, Faculty of Dentistry, Zanjan University of Medical Sciences, Zanjan, 4Department of Nanotechnology, Research Institute of Food Science and Technology, Mashhad, 5Department of Material and Metallurgical Engineering, University of Semnan, Semnan, 6Dental Materials Research Center, Department of Operative Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran Abstract: The aim of this in vitro study was to evaluate the effect of silica and aluminosilicate nanocomposite coating of zirconia-based dental ceramic by a sol–gel dip-coating technique on the bond strength of veneering porcelain to the yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) in vitro. Thirty Y-TZP blocks (10 mm ×10 mm ×3 mm) were prepared and were assigned to four experimental groups (n=10/group): C, without any further surface treatment as the control group; S, sandblasted using 110 µm alumina powder; Si, silica sol dip coating+ calcination; and Si/Al, aluminosilicate sol dip coating + calcination. After preparing Y-TZP samples, a 3 mm thick layer of the recommended porcelain was fired on the coated Y-TZP surface. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray analysis were used to characterize the coating and the nature of the bonding between the coating and zirconia. To examine the zirconia–porcelain bond strength, a microtensile bond strength (µTBS) approach was chosen. FT-IR study showed the formation of silica and aluminosilicate materials. XRD pattern showed the formation of new phases consisting of Si, Al, and Zr in coated samples. SEM showed the formation of a uniform coating on Y-TZP samples. Maximum µTBS values were obtained in aluminosilicate samples, which were significantly increased compared to control and sandblasted groups (P=0.013 and P

The shape and sorption behaviour of pores in mesoporous ordered silica films are determined from grazing-incidence small-angle X-ray scattering data., Mesoporous silica films templated by pluronic P123 were prepared using spin and dip coating. The ordered cylindrical structure within the films deforms due to shrinkage during calcination. Grazing-incidence small-angle X-ray scattering (GISAXS) measurements reveal that both the unit cell and the cross section of the pores decrease in size, mainly normal to the surface of the substrate, leading to elliptical cross sections of the pores with axis ratios of about 1:2. Water take-up by the pores upon changing the relative humidity can be monitored quantitatively by the shift in the critical angle of X-ray reflection as seen by the Yoneda peak.

When bioactive coatings are applied to medical implants by means of sol-gel dip coating technique, the biological proprieties of the implant surface can be modified to match the properties of the surrounding tissues. In this study organo-inorganic nanocomposites materials were synthesized via sol-gel. They consisted of an inorganic zirconium-based and silica-based matrix, in which a biodegradable polymer (the poly-ϵ-caprolactone, PCL) was incorporated in different weight percentages. The synthesized materials, in sol phase, were used to dip-coat a substrate of commercially pure titanium grade 4 (CP Ti gr. 4) in order to improve its biological properties. A microstructural analysis of the obtained films was carried out by scanning electron microscopy (SEM) and attenuated total reflectance (ATR) Fourier transform infrared spectroscopy (FT-IR). Biological proprieties of the coated substrates were investigated by means of in vitro tests.

The Structure of the Silumin Coat on Alloy Cast Steels The work presents the analysis results of the structure of the coat obtained by dipping in silumin AlSi5 of two grades of alloy cast steel: GX6CrNiTi18-10 (LH18N9T) and GX39Cr13 (LH14). The temperature of the silumin bath was 750±5°C, and the hold-up time of the cast steel element τ = 180 s. The absolute thickness of the coat obtained in the given conditions was g = 104 μm on cast steel GX6CrNiTi18-10 and g = 132 μm on GX39Cr13. The obtained coat consisted of three layers of different phase structure. The first layer from the base "g1" was constructed of the phase AlFe including Si and alloy additives of the tested cast steel grades: Cr and Ni (GX6CrNiTi18-10) and Cr (GX39Cr13). The second layer "g1" of intermetallic phases AlFe which also contains Si and Cr crystallizes on it. The last, external layer "g2" of the coat consists of the silumin containing the intermetallic phases AlFeSi which additionally can contain alloy additives of the cast steel. It was shown that there were no carbides on the coat of the tested cast steels which are the component of their microstructure, as it took place in the case of the coat on the high speed steels.

We demonstrate a simple but highly efficient technique to introduce multifunctional properties to cellulose fiber networks by wetting them with ethyl-cyanoacrylate monomer solutions containing various suspended organic submicrometer particles or inorganic nanoparticles. Solutions can be applied on cellulosic surfaces by simple solution casting techniques or by dip coating, both being suitable for large area applications. Immediately after solvent evaporation, ethyl-cyanoacrylate starts cross-linking around cellulose fibers under ambient conditions because of naturally occurring surface hydroxyl groups and adsorbed moisture, encapsulating them with a hydrophobic polymer shell. Furthermore, by dispersing various functional particles in the monomer solutions, hydrophobic ethyl-cyanoacrylate nanocomposites with desired functionalities can be formed around the cellulose fibers. To exhibit the versatility of the method, cellulose sheets were functionalized with different ethyl-cyanoacrylate nanocomposite shells comprising submicrometer wax or polytetrafluoroethylene particles for superhydophobicity, MnFe 2O 4 nanoparticles for magnetic activity, CdSe/ZnS quantum dots for light emission, and silver nanoparticles for antimicrobial activity. Morphological and functional properties of each system have been studied by scanning and transmission electron microscopy, detailed contact angle measurements, light emission spectra and E. coli bacterial growth measurements. A plethora of potential applications can be envisioned for this technique, such as food and industrial packaging, document protection, catalytic cellulosic membranes, textronic (electrofunctional textiles), electromagnetic devices, authentication of valuable documents, and antimicrobial wound healing products to name a few. © 2011 American Chemical Society.

Telah dilakukan studi deposisi lapisan tipis ZnO menggunakan teknik Dip-Coating (Teknik Celup) diatas material kaca yang merupakan salah satu material yang diduplikasikan sebagai kaca ITO pada sel surya. Lapisan tipis ZnO dibuat dengan cara sol-gel yang mencampurkan beberapa material kedalamnya sehingga didapatkan sol-gel ZnO. Pada penelitian ini dilakukan beberapa variasi celup yaitu dua kali dan empat kali celup. Deposisi lapisan tipis ZnO diatas kaca preparat. Berdasarkan hasil karakterisasi menggunakan difraksi sinar-X diperoleh bahwa lapisan yang dihasilkan merupakan amorf. Pada variasi celup kedua dan keempat didapatkan bentuk amorf dari lapisan tipis ZnO tersebut. ZnO thin film deposition has been done using Dip-Coating technique on glass material which is one of the materials that is duplicated as ITO glass in solar cell. A thin layer of ZnO is made by sol-gel which mixes several materials into it to obtain ZnO sol-gel. In this research, there are several variations of dye that is twice and four times the dye. Deposition of a thin film ZnO over a glass preparation. Based on the characterization results using X-ray diffraction obtained that the resulting layer is amorphous. In the second and fourth dip variations obtained the amorphous form of the ZnO thin film. Keywords : Thin Film ZnO; Sol Gel ZnO; Dip Coating; X-Ray Diffraction; Deposition Study

Despite its large band gap, ZnO has wide applicability in many fields ranging from gas sensors to solar cells. ZnO was chosen over other materials because of its large exciton binding energy (60 meV) and its stability to high-energy radiation. In this study, ZnO nanorods were deposited on ITO glass via a simple dip coating followed by a hydrothermal growth. The morphological, structural and compositional characteristics of the prepared films were analyzed using X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM), and ultraviolet-visible spectroscopy (UV-Vis). Photoelectrochemical conversion efficiencies were evaluated via photocurrent measurements under calibrated halogen lamp illumination. Thin film prepared at 120 °C for 4 h of hydrothermal treatment possessed a hexagonal wurtzite structure with the crystallite size of 19.2 nm. The average diameter of the ZnO nanorods was 37.7 nm and the thickness was found to be 2680.2 nm. According to FESEM images, as the hydrothermal growth temperature increases, the nanorod diameter become smaller. Moreover, the thickness of the nanorods increase with the growth time. Therefore, the sample prepared at 120 °C for 4 h displayed an impressive photoresponse by achieving high current density of 0.1944 mA/cm2.

ZnO is widely used as a functional material because it has a wide and direct band gap, large excitons binding energy, and excellent chemical and thermal stability. ZnO is a semiconductor material which is widely used as transparent electrodes in solar cells, chemical and gas sensors and light emitting diodes, due to its unique electrical and optical properties. Zinc oxide (ZnO) thin films were deposited on glass substrate by dip coating technique. The effects of sol aging time on the deposition of ZnO films were studied by using the field emission scanning electron microscopy (FE-SEM) and optical transmission techniques. Thin films of ZnO were prepared on glass substrate and annealed at 300 C, 350 C and 400 C. The increase in sol aging time resulted in a gradual improvement in crystallinity. Effect of sol aging on optical transparency is quite obvious through increased transmission with prolonged sol aging time. Interestingly, 72-168 h sol aging time was found to be optimal to achieve smooth surface morphology, good crystallinity and high optical transmittance which were attributed to an ideal stability of solution. The UV-Vis transmittance spectrum of synthesized sample suggests the optical band gap value of 3.2 eV. Dip coating technique create ZnO films with potential for application as transparent electrodes in optoelectronic devices such as solar cell.

Cd(II) ions can be incorporated into the channels of mesostructured titania films, using the evaporation-induced self-assembly (EISA) approach, up to a record high Cd/Ti mole ratio of 25%. The film samples were obtained by spin or dip coating from a mixture of 1-butanol, [Cd(H(2)O)(4)](NO(3))(2), HNO(3), and Ti(OC(4)H(9))(4) and then aging the samples under 50% humidity at 30 degrees C (denoted as meso-xCd(II)-yTiO(2)). The nitrate ions, from nitric acid and cadmium nitrate, play important roles in the assembly process by coordinating as bidentate and bridged ligands to Cd(II) and Ti(IV) sites, respectively, in the mesostructured titania films. The film samples can be reacted under a H(2)S (or H(2)Se) gas atmosphere to produce CdS (or CdSe) on the channel surface and/or pore walls. However, the presence of such a large number of nitrate ions in the film samples also yields an extensive amount of nitric acid upon H(2)S (or H(2)Se) reaction, where the nanoparticles are not stable (they undergo decomposition back to metal ion and H(2)S or H(2)Se gas). However, this problem can be overcome by further aging the samples at 130 degrees C for a few hours before H(2)S (or H(2)Se) reaction. This step removes about 90% of the nitrate ions, eliminates the nitric acid production step, and stabilizes the CdS nanoparticles on the surface and/or walls of the pores of the coupled semiconductor films, denoted as meso-xCdS-yTiO(2). However, the H(2)Se reaction, additionally, needs to be carried at lower H(2)Se pressures in an N(2) atmosphere to produce stable CdSe nanoparticles on the surface and/or walls of the pores of the films, denoted as meso-xCdSe-yTiO(2). Otherwise, an excessive number of Se(8) particles form in the film samples.