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In dye-sensitized solar cells (DSSCs), materials classified as Transparent Conducting Oxides (TCOs) have the capacity to conduct electricity and transmit light at the same time. Their exceptional blend of optical transparency and electrical conductivity makes them popular choices for transparent electrodes in DSSCs. Fluorine Tin Oxide (FTO) was utilized in this experiment. The optical and electrical characteristics of TCOs may be negatively impacted by their frequent exposure to hostile environments and potential for deterioration. TCOs are coated with passivating layers to increase their performance, stability, and defense against environmental elements including oxygen, moisture, and chemical pollutants. Because of its superior dielectric qualities, strong chemical stability, and suitability with TCO materials, aluminum oxide (Al2O3) was utilized as a passivating layer for the FTO. In this research work, Al2O3 was deposited via atomic layer deposition (ALD) to form thin mesoporous layers as a passivator in the photoanode (working electrode). The work focuses on finding an appropriate thickness of Al2O3 for optimum performance of the dye-sensitized solar cells. The solar simulation and sheet resistance analysis clearly showed 200 cycles of Al2O3 to exhibit an efficiency of 4.31%, which was the most efficient performance. The surface morphology and topography of all samples were discussed and analyzed. [ABSTRACT FROM AUTHOR]

Magnesium and its alloys are attractive temporary implants due to their biocompatibility and biodegradability. Moreover, Mg has good mechanical and osteoinductive properties. But magnesium and Mg alloys have one significant disadvantage: poor corrosion resistance in a physiological environment. Hence, a deposition of various layers on the surface of Mg alloys seems to be a good idea. The purpose of the article is to analyze the structure and morphology of two MgCa2Zn1 and MgCa2Zn1Gd3 alloys coated by SnO2 ALD (atomic layer deposition) films of various thickness. The studies were performed using scanning electron microscopy (SEM), X-ray fluorescence (XRF), and an X-ray diffractometer. The corrosion activity of the thin films and substrate alloys in a chloride-rich Ringer's solution at 37 °C was also observed. The corrosion tests that include electrochemical, immersion measurements, and electrochemical impedance spectroscopy (EIS) were evaluated. The results indicated that SnO2 had a heterogeneous crystal structure. The surfaces of the thin films were rough with visible pores. The corrosion resistance of SnO2 measured in all corrosion tests was higher for the thicker films. The observations of corrosion products after immersion tests indicated that they were lamellar-shaped and mainly contained Mg, O, Ca, and Cl in a lower concentration. [ABSTRACT FROM AUTHOR]

This paper presents the results of study on titanium dioxide thin films prepared by atomic layer deposition method on a silicon substrate. The changes of surface morphology have been observed in topographic images performed with the atomic force microscope (AFM) and scanning electron microscope (SEM). Obtained roughness parameters have been calculated with XEI Park Systems software. Qualitative studies of chemical composition were also performed using the energy dispersive spectrometer (EDS). The structure of titanium dioxide was investigated by X-ray crystallography. A variety of crystalline TiO2 was also confirmed by using the Raman spectrometer. The optical reflection spectra have been measured with UV-Vis spectrophotometry.

The article describes the results of a research on the surface morphology and optical properties of Al2O3, ZnO, and TiO2 thin films deposited by atomic layer deposition (ALD) for applications in silicon solar cells. The surface topography and elemental composition were characterised using a scanning electron microscope, and thickness was determined using an optical reflectometer. The samples were structurally examined using a Raman spectrometer. The structural variant was identified: for Al2O3 it is sapphire, for TiO2 it is anatase, and for ZnO it is wurtzite. Possibilities of minimising light reflection using single and double thin film systems below 5% were presented. For the first time, the effectiveness of these thin films on the current-voltage characteristics and electrical parameters of manufactured silicon solar cells was examined and compared. The solar cell with the highest efficiency of converting solar radiation into electricity was obtained for Al2O3/TiO2 and the efficiency of such a photovoltaic device was 18.74%. [ABSTRACT FROM AUTHOR]

Al2O3/TiO2 thin films were deposited onto monocrystalline silicon surfaces using an atomic layer deposition. Their surface morphology and optical properties were examined for their possible use in solar cells. The surface condition and chemical composition were characterized using a scanning electron microscope and the thickness was measured using a spectroscopic reflectometer. The refractive index and the reflection characteristics were determined. First, the optical properties of the Al2O3 thin film and its influence on recombination in the semiconductor were examined. In this way, it can fulfil a double role in a solar cell. Since reflection reduction was only achieved in a narrow range, it was decided to use the Al2O3/TiO2 system. Thanks to this solution, the light reflection was reduced in a wide range (even below 0.2%). [ABSTRACT FROM AUTHOR]

Titanium dioxide thin films have been deposited on silicon wafers substrates by an atomic layer deposition (ALD) method. There optical parameters were investigated by spectroscopic ellipsometry and UV/VIS spectroscopy. A material with a refractive index of 2.41 was obtained. Additionally, in a wide spectral range it was possible to reduce the reflection from the silicon surface below 5%. The Raman spectroscopy method was used for structural characterization of anatase TiO2 thin films. Their uniformity and chemical composition are confirmed by a scanning electron microscope (SEM) energy dispersive spectrometer (EDS). [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to improve the efficiency of dye-sensitized solar cells (DSSCs) which present promising low-cost alternative to the conventional silicon solar cells mainly due to comparatively low manufacturing cost, ease of fabrication and relatively good efficiency. One of the undesirable factor in DSSCs is the electron recombination process that takes place at the transparent conductive oxide/electrolyte interface, on the side of photoelectrode. To reduce this effect in the structure of the solar cell, a TiO2 blocking layer (BL) by atomic layer deposition (ALD) was deposited. Design/methodology/approach: Scanning electron microscope, Raman and UV-Vis spectroscopy were used to evaluate the influence of BL on the photovoltaic properties. Electrical parameters of manufactured DSSCs with and without BL were characterized by measurements of current-voltage characteristics under standard AM 1.5 radiation. Findings: The TiO2 BL prevents the physical contact of fluorine-doped tin oxide (FTO) and the electrolyte and leads to increase in the cell's overall efficiency, from 5.15 to 6.18%. Higher density of the BL, together with larger contact area and improved adherence between the TiO2 layer and FTO surface provide more electron pathways from TiO2 to FTO which facilitates electron transfer. Originality/value: This paper demonstrates that the introduction of a BL into the photovoltaic device structure is an important step in technology of DSSCs to improve its efficiency. Moreover, the ALD is a powerful technique which allows for the highly reproducible growth of pinhole-free thin films with excellent thickness accuracy and conformality at low temperature. [ABSTRACT FROM AUTHOR]

This paper presents some results of investigations on aluminum oxide Al2O3 thin films prepared by the atomic layer deposition method on polished monocrystalline silicon. It has been described how the technological parameters of the deposition process, like the number of cycles and substrate temperature, influenced the optical properties and morphology of prepared thin films. Their physical and optical properties like thickness, uniformity and refractive index have been investigated with spectroscopic ellipsometry, atomic force microscopy and UV/vis optical spectroscopy. [ABSTRACT FROM AUTHOR]

The paper presents the possibility of using AlO antireflection coatings deposited by atomic layer deposition ALD. The ALD method is based on alternate pulsing of the precursor gases and vapors onto the substrate surface and then chemisorption or surface reaction of the precursors. The reactor is purged with an inert gas between the precursor pulses. The AlO thin film in structure of the finished solar cells can play the role of both antireflection and passivation layer which will simplify the process. For this research 50×50 mm monocrystalline silicon solar cells with one bus bar have been used. The metallic contacts were prepared by screen printing method and AlO antireflection coating by ALD method. Results and their analysis allow to conclude that the AlO antireflection coating deposited by ALD has a significant impact on the optoelectronic properties of the silicon solar cell. For about 80 nm of AlO the best results were obtained in the wavelength range of 400 to 800 nm reducing the reflection to less than 1%. The difference in the solar cells efficiency between with and without antireflection coating was 5.28%. The LBIC scan measurements may indicate a positive influence of the thin film AlO on the bulk passivation of the silicon. [ABSTRACT FROM AUTHOR]

The article describes biomaterials and surgical instruments, in particular surgical cutting tools. In addition, the functions of coatings and the layer vapor deposition methods are described. In the experimental component of the study, zinc oxide thin film was deposited on the surgical knife blades by the atomic layer deposition (ALD) method with a varying number of cycles. The structures of the deposited thin films were investigated using a Raman spectrometer and the surface topography of the samples was examined using atomic force microscopy and scanning electron microscopy. The adhesion of the thin films was tested using the micro-scratch method. The corrosion resistance was also tested. Surgical instruments coated with non-allergenic metal oxide coatings, containing metal structures that reduce the growth of bacteria, could significantly decrease the risk of undesirable reactions of the body during and after surgery. [ABSTRACT FROM AUTHOR]

Magnesium alloys have been investigated as temporary biomaterials for orthopedic applications. Despite their high osseointegration and mechanical (bone-like) properties, Mg alloys quickly degrade in simulated physiological media. Surface coatings can be deposited onto Mg alloys to slow the corrosion rate of these biomaterials in chloride-rich environments. TiO2 films show high potential for improving the corrosion resistance of magnesium alloys. This article presents the structural observations and corrosion behavior of TiO2 thin films deposited onto a MgCa2Zn1Gd3 alloy using atomic layer deposition (ALD). Surface morphologies were observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM), and Raman analysis of the deposited TiO2 films was also carried out. The corrosion behavior of the uncoated alloy and the alloy coated with TiO2 was measured in Ringer's solution at 37 °C using electrochemical and immersion tests. The microscopic observations of the TiO2 thin films with a thickness of about 52.5 and 70 nm showed that the surface morphology was homogeneous without visible defects on the TiO2 surface. The electrochemical and immersion test results showed that the thin films decreased the corrosion rate of the studied Mg-based alloy, and the corrosion resistance was higher in the thicker TiO2 film. [ABSTRACT FROM AUTHOR]

The main goal of the carried out tests was to analyze the influence of the surface modification of a substrate by depositing composite ZnO layers by the Atomic Layer Deposition (ALD) method. The samples were subjected to preliminary surface modification consisting of being sandblasted and electropolished. A ZnO layer was applied to the prepared substrates by the ALD method. As a precursor of ZnO, diethylzinc (DEZ) was used, which reacted with water, enabling the deposition of the thin films. The chamber temperature was as follows: T = 100–300 °C. The number of cycles was 500 and 1500. As part of the assessment of the physicochemical properties of the resulting surface layers, the tests of chemical composition of the layer, pitting corrosion, impedance corrosion, adhesion to the metal substrate, morphology surface, and wettability were carried out. On the basis of the obtained research, it was found that a composite ZnO layer deposited onto a substrate previously subjected to the electrochemical polishing process has more favorable physicochemical properties. Moreover, an influence of temperature and the number of cycles of the deposition process on the obtained properties was observed, where the ZnO layer was characterized by more favorable properties at a temperature of 200–300 °C at 1500 cycles of the deposition process. [ABSTRACT FROM AUTHOR]

The use of nickel-titanium (NiTi) alloy in implants, despite its good biocompatibility, is not entirely inert to the human body. To reduce nickel ions and improve the hemocompatibility of implants for blood contact, a thin layer of tantalum oxide (Ta 2 O 5) was proposed. Although nitinol self-coats a thin layer of TiO 2 titanium dioxide to protect against corrosion, many studies emphasized the need to enhance this protection. Therefore, in the first stage of this study, the alloy surface was prepared by four different methods, producing a passive interlayer. Then a Ta 2 O 5 coating was applied, and the properties with and without the layer were investigated. The resulting coating was applied to the NiTi alloy in the initial state and passivated in water, and perhydrol showed a high adhesion to the substrate. However, the coating deteriorated resistance to pitting corrosion and increased surface wettability. For the initial condition and passivation in perhydrol, the coating affected the reduction of bacterial adhesion to the substrate. Surface preparation directly influenced the optimization of the deposition of this layer on implants in contact with blood. The results suggest that the properties studied were strongly correlated with the type of passive interlayer. • The results of corrosion resistance tests showed that the Ta2O5 layer improves pitting corrosion resistance regardless of the method of passivation substrate. • The application of Ta2O5 coating, regardless of the application parameters and surface preparation, decreased the number of attached bacterial colonies to the NiTi alloy substrate. • The scratch test results confirmed an excellent adhesion of the layer to the substrate compared to other layers applied with the ALD method. • Surface wettability tests showed that the Ta2O5 film reduced the wetting angle, providing hydrophilic properties (θ < 90°), which could negatively affect hemocompatibility. [ABSTRACT FROM AUTHOR]