Treated Glass Surfaces Research Articles

Self-cleaning anti-fog micro-nanostructures by laser marker patterning nickel-coated glass

To minimise potential damage and crack on glass induced by direct laser patterning, this study employed a cost-effective laser marker for the rapid ablation of nickel (Ni)-coated glass substrates to fabricate super-hydrophilic micro-nanostructures. Most of laser energy was consumed by ablating Ni film with minimal deposited on glass, leading to shallow micron structure to support the nanostructure. The investigation systematically explored the influence of Ni thickness and laser scan hatch distance on the resultant properties of the treated glass by scanning electron microscope (SEM), atomic force microscope (AFM), confocal microscope, X-ray photoelectron spectroscopy (XPS), gonoimeter, spectrophotometer and real-time assessments of anti-fogging and self-cleaning performance. The treated glass surface exhibited a hierarchical micro-nanostructure featuring a quasi-periodical hillock-hollow micron structure and widely distributed nanoparticles. This unique surface structure yielded an exceptionally low contact angle of 0°, exhibiting remarkable self-cleaning and antifogging capabilities that persisted for over 9 months without apparent degradation. Such durable exceptional self-cleaning and anti-fog performance was rarely been reported in the literature and was attributed to the stable micro-nanostructure and robust chemical bondings present on the surface, showcasing significant potential for widespread commercial applications.

Self-Moving blooming drops of dimethyl sulfoxide containing benzyne intermediate for solutal transport

Drop motion can be achieved on surfaces with low to negligible contact angle hysteresis. The droplets can be made to move under the influence of an external force or droplets can show self-propelled motion. The studies on drop motion are crucial for the design and application of surfaces for controlling drop motion. In this work, self-propelled motion of non-aqueous drops containing an active solute on a total wetting glass surface is reported. The benzyne intermediate 2(-Trimethylsilyl) phenyltrifluoromethane sulfonate (TPS) in DMSO (dimethyl sulphoxide) and octadecylamine in hexadecane were used as active components of binary/ternary drops showing self-induced motion. When drops of these were casted on high-temperature treated glass surface, random drop motion was observed followed by complete spreading of the drop. In case of DMSO, the drop periphery expanded with time while forming a rim, a central spherical cap inside the spreading drop was formed that shows random motion. This behaviour of drop was referred as a confused spreading-blooming drop, as spreading of DMSO drop occurs with rim formation outside and a self-moving drop formed inside the casted area. The unique non-aqueous drop spreading was evaluated by varying the solutal concentrations. This work depicts the unique combination of surface and drops showing potential application in self-propelled drop motion.

Influence of Glass Surface Modification on Thin Film Copper Electrodes

We investigate the impact of the glass surface on the structural and electrical properties of Ti/Cu film stacks as well as single Ti adhesion layer, by modifying Corning® Eagle XG® glass surfaces using four acids common in TFT-LCD microfabrication processes. Atomic force microscopy results indicate significant change of the surface topography of Ti and Cu, particularly found on hydrofluoric acid treated glass surfaces. The film microstructures are characterized by a comprehensive analysis using Bragg, grazing incidence and in-plane X-ray diffraction, and X-ray reflectivity methods as well as the transmission electron microscopy. The sheet resistance was measured using the four-point probe method. We demonstrate the role of the glass surface state through its impact on the structural and electrical properties of Ti/Cu electrodes emanating from glass surface treatments.

Building façade-level correlates of bird–window collisions in a small urban area

Abstract Urbanization increasingly exposes birds to multiple sources of direct anthropogenic mortality. Collisions with buildings, and windows in particular, are a top bird mortality source, annually causing 365–988 million fatalities in the United States. Correlates of window collision rates have been studied at the scale of entire buildings and in relation to the surrounding landscape, and most studies have only assessed correlates for all birds combined without considering season- and species-specific risk factors. In Stillwater, Oklahoma, USA, we conducted bird collision surveys at 16 buildings to assess building structural-, vegetation-, and land cover-related collision correlates. Unlike past studies, we focused at the scale of individual building façades, and in addition to considering correlates for total collisions, we assessed correlates for different seasons and separately for 8 collision-prone species. Several façade-related features, including proportional glass coverage, façade length, and façade height, were positively associated with total collisions and collisions for most separate seasons and species. Total collisions were also greater at alcove-shaped façades than flat, curved, and portico-shaped façades. We found that collision correlates varied among seasons (e.g., surrounding lawn cover important in summer and fall, but not spring) and among species (e.g., surrounding impervious cover positively and negatively related to collisions of Painted Bunting [Passerina ciris] and American Robin [Turdus migratorius], respectively). Given the importance of glass proportion, collision reduction efforts should continue to focus on minimizing and/or treating glass surfaces on new and existing buildings. Our species- and season-specific assessments indicate that management of some collision risk factors may not be equally effective for all seasons and species. Future research, policy, and management that integrates information about collision risk for all bird species and seasons, and at multiple scales from building façades to the surrounding landscape, will be most effective at reducing total mortality from bird–window collisions.

Thermodynamic Analysis of the Reactions of Formation of Potassium, Zinc, and Aluminum Phosphates during the Electron-Beam Processing of Blue-Green Glass SZS23

Thermodynamic functions of the reactions of phosphate-oxide formation during the electron-beam processing of blue-green glass SZS23 are determined. The treated glass surface is found to be enriched with aluminum. It is supposed that the composition of the surface layer is to approaches the composition of aluminum orthophosphate as a result of processing.

Development of thermostable amylase enzyme from Bacillus cereus for potential antibiofilm activity

The marine bacterial strain Bacillus cereus was used to produce amylase enzyme and has excellent alkali-stable and thermostable enzymatic activity. The combined effects of pH, temperature and incubation time on amylase activity were studied using response surface methodology. The amylase enzyme activity was also determined in the presence of various metal ions, chelating agents, detergents and the results showed that the maximum enzyme activity was observed in the presence of calcium chloride (96.1%), EDTA (63.4%) and surf excel (90.6%). The amylase enzyme exhibited excellent antibiofilm activity against marine derived biofilm forming bacteria Pseudomonas aeruginosa and Staphylococcus aureus in microtiter plate assay and congo red assay. Light and confocal laser scanning microscopic (CLSM) analysis were also used to confirm the potential biofilm activity of amylase enzyme. The CLSM analysis showed the inhibition of complete biofilm formation on amylase enzyme treated glass surface. Further in vivo toxicity analysis of amylase enzyme was determined against marine organisms Dioithona rigida and Artemia salina. The results showed that there is no morphological changes were observed due to the minimal toxicity of amylase enzyme. Overall these findings suggested that marine bacterial derived amylase enzyme could be developed as potential antibiofilm agent.

Low-frequency electrohydrodynamic convection patterns in nematic liquid crystal aligned using parallel-oriented nanofiber

Parallel-aligned poly(vinyl alcohol) (PVA) nanofiber with a diameter of 240 ± 60 nm and an alignment parameter (S) of 0.95 ± 0.16 was obtained by a gap collector electrospinning that used copper (Cu) as a collector. The sandwiched cells (the horizontal-view and longitudinal-view) nematic liquid crystal was prepared by treating glass surfaces with the aligned PVA nanofiber to provide uniform anchoring of the director. When an electric field was applied to these samples, the electrohydrodynamic convection (EHC) pattern was observed. In the longitudinal-view cells, above a threshold voltage at low frequency, a typically low-frequency EHC rolls i.e., a Williams domain (WD) pattern was observed. By increasing the voltage, a fluctuating Williams domain (FWD) and grid patterns (GPs) could also be observed. In the transverse-view cells, at low-frequency regimes, WD, sawtooth patterned (STP), and dynamic scattering mode (DSM) patterns were observed. By replacing the conventional rubbing method with the use of parallel-aligned nanofibers, the well-known EHC phenomenon also could be observed.

Acoustic actuation of in situ fabricated artificial cilia

We present on-chip acoustic actuation of in situ fabricated artificial cilia. Arrays of cilia structures are UV polymerized inside a microfluidic channel using a photocurable polyethylene glycol (PEG) polymer solution and photomasks. During polymerization, cilia structures are attached to a silane treated glass surface inside the microchannel. Then, the cilia structures are actuated using acoustic vibrations at 4.6 kHz generated by piezo transducers. As a demonstration of a practical application, DI water and fluorescein dye solutions are mixed inside a microfluidic channel. Using pulses of acoustic excitations, and locally fabricated cilia structures within a certain region of the microchannel, a waveform of mixing behavior is obtained. This result illustrates one potential application wherein researchers can achieve spatiotemporal control of biological microenvironments in cell stimulation studies. These acoustically actuated, in situ fabricated, cilia structures can be used in many on-chip applications in biological, chemical and engineering studies.

Effects of wettability on the growth of Scenedesmus obliquus biofilm attached on glass surface coated with polytetrafluoroethylene emulsion

Microalgae biofilm that adhered on the supporting material surface has a potential of high biomass productivity. The characteristics of material surface are very important for the microalgae growth, especially, the wettability. To improve the growth of microalgae biofilm, polytetrafluoroethylene (PTFE) emulsion was sprayed onto the glass surface to change its wettability in the study. The experimental results indicated that the microstructure of Scenedesmus obliquus biofilm on the treated glass surface was more porous due to the enhanced bubble adhesion. Favorable porous structure in the S. obliquus biofilm could enhance the nutrients and CO2 mass transfer to the microalgae cells within biofilm for more biomass accumulation. Therefore, the biofilm biomass production increased by 16.86%–122.03 g/m2 on the surface with a contact angle of 64° compared with that of 104.42 g/m2 on the untreated surface. Subsequently, flow rate of pre-mixed medium and inlet height of the photobioreactor was optimized. The maximum areal biomass concentration of S. obliquus biofilm on the PTFE-glass surface with a contact angle of 64° achieved 177.89 g/m2 with the mean growth rate of 9.88 g/m2/d in a photobioreactor with 2.5 cm inlet height under 3.5 ml/min of pre-mixed medium flow rate.

P-182: Functional Coatings for Display Applications by a Spray Process

Antiglare coatings were spray coated on plasma treated glass surfaces followed by low temperature curing at 150 °C for 1 hour. The anti-glare coatings with embedded mono-dispersed latex particles can reach a pencil hardness of ≥8H, and a gloss range of 40 to 90 GU. In addition, a novel anti-fingerprint coating was discussed and showed significantly reduced fingerprint visibility and improved easy-to-clean properties.

Dewetting Dynamics of a Solid Microsphere by Emulsion Drops

A novel micropipet technique was developed to quantify the dewetting dynamics of individual microsphere particles by emulsified viscous crude oil drops in aqueous media. This technique allowed dynamic microscale receding contact angles of water to be measured in situ for solid–oil–water systems. System parameters, including modification of glass microspheres and characteristics of oil drops, were varied to study their effect on dewetting dynamics of the systems. Increasing solvent dosage in viscous oil was found to decrease static receding contact angle of water for clean and bitumen-treated glass surfaces, but showed a negligible effect on static receding contact angle for ethyl cellulose (EC)-treated glass surface. Interestingly, dynamic dewetting behavior exhibited a strong dependence on surface modification and the addition of solvent to viscous oil. No dewetting dynamics was observed for clean hydrophilic glass surface. For bitumen- or EC-treated glass surfaces, more rapid dewetting dynamics of water were determined with increasing addition of solvent to viscous oil. Both de Gennes viscous dissipation hydrodynamic and the Blake/Haynes molecular-kinetic models were developed for the current system to understand the observed dynamic dewetting characteristics.

Effect of HF and Plasma Treated Glass Surface on Vapor Phase-Polymerized Poly(3,4-ethylenedioxythiophene) Thin Film : Part I

In this study, in order to investigate how consecutive treatments of glass surface with HF acid and water vapor/Ar plasma affect the quality of 3-aminopropyltriethoxysilane self-assembled monolayer (APS-SAM), poly(3,4-ethylenedioxythiophene) (PEDOT) thin films were vapor phase-polymerized immediately after spin coating of FeCl3 and poly-urethane diol-mixed oxidant solution on the monolayer surfaces prepared at various treatment conditions. For the film characterization, various poweful tools were used, e.g., FE-SEM, an optical microscope, four point probe, and a contact angle analyzer. The characterization revealed that HF treatment is not desirable for the synthesis of a high quality PEDOT thin film via vapor phase polymerization method. Rather, sole treatment with plasma noticeably improved the quality of APS-SAM on glass surface. As a result, a highly dense and smooth PEDOT thin film was grown on uniform oxidant film-coated APS monolayer surface.

Plasma Treatment of Glass Surfaces Using Diffuse Coplanar Surface Barrier Discharge in Ambient Air

We report a study on the treatment of flat glass surfaces by ambient air atmospheric pressure plasma, generated by a dielectric barrier discharge of coplanar arrangement of the electrode system—the diffuse coplanar surface barrier discharge (DCSBD). The plasma treatment of glass was performed in both static and dynamic modes. With respect to wettability of the glass surface, treatment in static mode resulted in non-uniform surface properties, whereas dynamic mode provided a fully uniform treatment. A water contact angle measurement was used to determine the efficiency of plasma treatments in dynamic mode and also to investigate a hydrophobic recovery of plasma treated glass surfaces. The X-ray photoelectron spectroscopy measurements showed a decrease of overall carbon concentrations after plasma treatment. A deconvolution of C1s peak, showed that a short plasma treatment led to decrease of C–C bonds concentration and increases of C–O and O–C=O bond concentrations. An enhancing influence of the glass surface itself on DCSBD diffuse plasma was observed and explained by different discharge onsets and changes in the electric field distribution.

Smectic C liquid crystal growth and memory effect through surface orientation by carbon nanotubes

A smectic C liquid crystal texture consisting of well oriented distinct local single crystals was grown using predefined orientation of single wall carbon nanotubes (SWCNTs) adsorbed on a SiOx layer deposited on a ITO treated glass surface. The orientation features of the SWCNTs were analyzed by microtexture analysis and polarized Raman spectroscopy. It was found that the surface memory effect, induced by the SWCNT/SiOx/ITO/glass surface and manifested in the preservation of the smectic C texture in the nematic phase, was many times stronger than memorization promoted by conventional SiOx/ITO/glass and ITO/glass surfaces, usually used for liquid crystal orientations. We observe surface anchoring and memorization strength reinforcement due to trapping of liquid crystal bulk charges by the SWCNTs (surface charge density increase). The SWCNT/SiOx/ITO/glass surface is found to cause a substantial enlargement of the smectic C distinct local single crystals as compared to SiOx/ITO/glass and ITO/glass surfaces. We also discuss the physical nature of the erasure activation energy components contributing to the surface memorization process.

Fabrication of Super-Hydrophobic Surfaces with Long-Term Stability

A novel approach was proposed to fabricate super-hydrophobic surfaces by depositing aggregates of fumed silica modified with hydroxy-terminated poly-dimethylsioxane and γ-aminopropyltriethoxysilane on surfaces of glass plates. The glass plates were treated with 2,3-epoxy propoxy propyltrimethoxysilicane based on an epoxy-amine system in advance. Aggregates of fumed silica were found to be chemically bonded to the treated glass surfaces and a surface possessing dual micron- and nanoscale hierarchical structures was observed on the super-hydrophobic surfaces. The laboratory testing results showed that the obtained surfaces possessed long-term super-hydrophobicity in air and maintained its super-hydrophobicity over a wide pH range.

Insecticidal Activity of Peumus boldus Molina Essential Oil against Sitophilus zeamais Motschulsky

In stored grains, the main agents diminishing production are insects, which can produce losses between 20% and 80% before harvest or under storage. The insecticidal properties of the essential oil of fresh leaves of Peumus boldus Molina against maize weevil (Sitophilus zeamais Motschulsky) adults were determined under laboratory conditions. The highest mortality (100%) was achieved at 4% concentration by contact with a treated glass surface. The same concentration in impregnated corn (Zea mays L.) grain, resulted in 98.7% mortality. Mortality by fumigant action at 6 h was 100% with 35 µL oil in 0.15 L (air volume). Concentrations 1, 2 and 4% of essential oil produced 0% F1 adult emergence. At 10 d of residual effect, the 4% concentration reached 63.7% mortality. All treatments were repellent to adults of S. zeamais and corn grain germination was not affected by any treatment.

Precise cell patterning using cytophobic self-assembled monolayer deposited on top of semi-transparent gold

This paper reports a simple and effective method for cell patterning by using a self-assembled monolayer (SAM)-treated glass surface which is surrounded by semi-transparent gold coated with another type of SAM. Specifically, a hydrophobic SAM, derived from 1-hexadecanethiol (HDT), was coated on the gold surface to prevent cell growth, and a hydrophilic SAM, derived from 3-trimethoxysilyl propyl-diethylenetriamine (DETA), was coated on the exposed glass surface to promote cell growth. The capabilities of this technique are as follows: 1) single-cell resolution, 2) easy alignment of the cell patterns to the structures already existing on the substrate, 3) visualization and verification of the predefined cytophobic/cytophilic pattern prior to cell growth, and 4) convenient monitoring cell growth at the same location for an extended long term period of time. Whereas a number of earlier techniques have demonstrated the single cell resolution, or visualization and verification of the cytophobic/cytophilic patterns prior to cell growth, we believe that our technique is unique in possessing all of these beneficial qualities at the same time. The distinguishing characteristic of our technique is, however, that the use of semi-transparent Cr/Au film allows for convenient brightfield pattern visualization and offers an advantage over previously developed methods which require fluorescent imaging. We have successfully demonstrated the patterning of four different kinds of cells using this technique: immortalized mouse hypothalamic neurons (GT1-7), mouse osteoblast cells (MC3T3), mouse fibroblast cells (NIH3T3) and primary rat hippocampal neurons. This study was performed with a specific ultimate application-the creation of a multi electrode array (MEA) with predefined localization of cell bodies on top of the electrodes, as well as predefined patterns for cell extensions to grow in between the electrodes. With that goal in mind, we have also determined critical parameters for patterning of each of these cell types, such as the minimum size of a cell-adherent island for exclusively anchoring one cell or two cells, as well as the width of the cytophilic pathway between two islands that enables cell extensions to grow, while preventing the anchoring of the cell bodies. Additionally, we have provided statistical analysis of the occupancy for various sizes and shape of cell-anchoring islands. As demonstrated here, we have developed a novel and reliable cell patterning technique, which can be utilized in various applications, such as biosensors or tissue engineering.

Simple nanofabrication of a superhydrophobic and transparent biomimetic surface

This paper describes a simple fabrication method for creating superhydrophobic and transparent glass surfaces that mimic natural surfaces such as lotus leaves, moth eyes or cicada wings. Nanostructured glass surfaces were created by a combination of colloidal lithography and plasma etching. A colloidal mask was formed simply by the spin coating of the polystyrene beads and with modification of the interparticle distance between the beads. The etching of the glasses was conducted by CF4 plasma. Tower-shaped nanostructures at an aspect ratio of 1:4 were treated using fluoroalkylsilane self-assembled monolayers (SAMs) to obtain the hydrophobic surfaces. The treated glass surfaces showed superhydrophobicity with a water contact angle of around 150° and a hexadecane contact angle of around 110°. Furthermore, the nanostructured glass was transparent to visible light.

Surface Properties of Superhydrophobic Coatings for Stone Protection

Superhydrophobic films are produced by a simple and low cost method. Silica (SiO2) nanoparticles are dispersed in solutions of Rhodorsil 224, a commercial poly(alkyl siloxane) which is used for the protection of outdoor cultural heritage objects, and the suspensions are sprayed on glass surfaces. It is shown that the siloxane-nanoparticle composite films prepared from dispersions of high particle concentrations (≥ 0.5% w/v) exhibit superydrophobic properties (high static contact angle and small hysteresis) which can be rationalized by the Cassie-Baxter model, according to quantitative measurements obtained by SEM images. Siloxane-nanoparticle films are then deposited (sprayed) on “Opuka”, a fine-grained argillite which was used for the restoration of the castle of Prague. It is shown that the treated stone surfaces exhibit superydrophobic properties, similar to the treated glass surfaces. The efficacy of the superhydrophobic films to protect Opuka is evaluated by performing water contact angle, water capillary absorption, water vapor permeability and colorimetric measurements. It is shown that the use of nanoparticles in the protective coating has a positive effect on the results of the aforementioned tests, except for the colorimetric measurements.

Characterization of PDMS-modified glass from cast-and-peel fabrication

In glass/poly(dimethylsiloxane) (PDMS) hybrid microfluidic chips, two different fabrication approaches are used: photolithographic or solid ink molds, or cast-and-peel methods. In the latter, a thin slab of PDMS is laid down and fluid channels are cut manually or by machine. The cast-and-peel approach has been used successfully for low-shear culture devices, among other applications. The main drawback, not reported to date, of cast-and-peel methods is that removal of PDMS (exposing the glass substrate) results in nanoscopic domains of PDMS still attached to the surface. This residual PDMS is not observable by eye, but affects the hydrophobicity of the device. Using contact angle measurement, atomic force and fluorescence microscopy, the changes in glass surfaces from the cast-and-peel technique were elucidated. This study demonstrates the enhanced protein (NeutrAvidin) adsorption on PDMS treated glass surfaces, and the potential influence of altered glass properties on microfluidic applications has been discussed as well.