Properties Of Films Research Articles

STUDY ON THE PROPERTIES OF DIAMOND FILMS ON CEMENTED CARBIDE SUBSTRATES BY SURFACE IMPLANTATION PRETREATMENT PROCESS

The deposition of diamond films on tungsten carbide-based tools can greatly improve the life and performance of cutting tools. However, the deposition of diamond coatings on cemented carbide (WC-Co) suffers from poor film-base bond strength. In this paper, diamond coatings were deposited of phytocrystalline metal micropowders (pure, Nb, Ti, Ta) pretreatment method and the properties of diamond films were analyzed by energy spectrometry (EDS), scanning electron microscopy (SEM), Raman spectroscopy and bonding strength test of diamond films. The results show that through the experiment of the pretreatment process of surface implanted crystal metal micropowder, the best implanted crystal metal micropowder was obtained, the surface quality of implanted crystal titanium (Ti) coating was improved, the diamond Raman peaks were sharp and the indentation cracks had a crack diameter of 389 [Formula: see text]m, which is small and has the highest bond strength. The pretreatment process of phytocrystalline diamond micropowder can deposit high-performance diamond coatings and improve the bonding strength between the coating and the substrate film base.

Anti-Reflection Property of SiO2 Composite Films for Solar Cell

In this study, anti-reflection property of SiO2 based composite films were investigated. For this purpose, SiO2/TiO2, SiO2/ZnO and SiO2/TiO2/ZnO composite films were prepared using a sol-gel technique and coated on glass slides. Polyethylene glycol (PEG) with molecular weight of 1500 g/mol was inserted into the SiO2 composite film as a porogen to decrease the refractive index and improve the anti-reflection property of the as-prepared film. The SiO2 films with pore structures were successfully obtained. The PEG modified SiO2/ZnO (SiO2/PEG/ZnO) film provided a water contact angle close to the water contact angle of a superhydrophilic surface. In addition, the SiO2/PEG/ZnO film exhibited the highest average transmittance of 92.7% higher than that of the uncoated glass slide. The photovoltaic conversion efficiency of the solar cell coated with the SiO2/PEG/ZnO film was very close to that of the solar cell without the film coating. Hence, the results exhibited that the SiO2/PEG/ZnO film with anti-reflection and photovoltaic conversion efficiency has a potential application on solar cells.

Investigation of the microstructural, surface, and optical properties of WO3-doped ZnO thin films

The paper investigates the microstructural characteristics, surface features, and optical properties of WO3-doped ZnO thin film. The deposited samples exhibit polycrystalline characteristics, with reflections corresponding to bimetal oxides and metals. Specifically, ZnO shows (101) and (200) reflections, while (400) reflections are observed in the WO3 phase of the deposited sample. The crystallite sizes of the ZnO metal oxide phase in the film are 85 nm and 55 nm, while the crystallite size of the Zn nanoparticles is found to be 47 nm. The atomic concentrations of W and Zn are 53.4 % and 46.6 % for films deposited on uncoated glass, and 41.2 % and 58.8 %, for films deposited onto ITO-coated glass, respectively. An optical band gap value of 3.40 eV was obtained for both films. It was found that certain properties remain relatively unchanged despite variations in the substrate.

Effect of different metallic doping elements on the physical properties of iron oxide thin films

This study investigates the physical properties of pure and Co, Cr, Mn, and Ni-doped Fe2O3 thin films fabricated using spray pyrolysis techniques on glass substrates. The primary aim is to understand how doping influences the structural, optical, and dielectric properties of Fe2O3 thin films. The deposition parameters were kept constant for all samples, with a fixed dopant concentration of 3 weight percent (wt%). X-ray diffraction (XRD) analysis revealed a single diffraction peak indexed as (104), decreasing in crystallite size from 17.27 nm for the pure film to approximately 11.5 nm for all doped films. Field emission scanning electron microscopy (FE-SEM) images displayed non-homogeneous grain formation, characterized by an average grain size larger than the crystallite size, indicating agglomeration. The optical band gap value shifted from 2.54 eV for the pure film to higher values upon doping with various elements, signifying direct allowed transitions. Changes in refractive index dispersion with wavelength were observed based on the dopant type. The application of the Spitzer-Fan model revealed an increase in high-frequency dielectric constant upon doping compared to the pure film, varying across different dopants. Photoluminescence (PL) spectra recorded under excitation at 340 nm exhibited multiple emission peaks within the spectral range of 399 to 600 nm.

Optical properties of CdO thin films

Cadmium Oxide thin films were deposited on glass substrate by spray pyrolysis technique at different temperatures (300,350,400, 500)oC. The optical properties of the films were studied in this work. The optical band-gap was determined from absorption spectra, it was found that the optical band-gap was within the range of (2.5-2.56)eV also width of localized states and another optical properties.

Investigation of Dielectric and Piezoelectric Properties of Polyvinylidene Fluoride Films Reinforced with Anatase Phase Titanium Dioxide for Pressure Sensing

Investigation of Dielectric and Piezoelectric Properties of Polyvinylidene Fluoride Films Reinforced with Anatase Phase Titanium Dioxide for Pressure Sensing

Tailoring silk-based covering material with matched mechanical properties for vascular tissue engineering

Vascular covered stents play a significant therapeutic role in cardiovascular diseases. However, the poor compliance and biological inertness of commercial materials cause post-implantation complications. Silk fibroin (SF), as a biomaterial, possesses satisfactory hemocompatibility and tissue compatibility. In this study, we developed a silk film for use in covered stents by employing a layer-by-layer self-assembly strategy with regenerated SF on silk braiding fabric. We investigated the effects on the mechanical properties of the silk films in detail, which were closely correlated with fabric parameters and layer-by-layer self-assembly. The results showed that there was a significant relationship between these factors and both the compliance and mechanical strength. The 1 × 2/90°/100/SF6 film exhibited excellent mechanical properties. Notably, compliance reached 2.6%/100 mmHg, matching that of the human saphenous vein. Thus, this strategy shows promise in developing a novel covered stent, with biocompatible and comprehensive mechanical properties, and significant potential for clinical applications.

Advancement of Electro-Optical Properties through Changes in the Physicochemical Composition of Hybrid Thin Films by Doping Reduced Graphene Oxide into a Sol-Gel Process Solution.

A hybrid thin film was fabricated by doping graphene oxide into a sol-gel solution containing a mixture of zirconium, bismuth, and indium oxide. The thin film was fabricated using a brush coating process. The graphene oxide doping ratios used were 0, 5, and 15 wt%. During the thin film fabrication process, the produced sol-gel solution generates a contractile force due to the shear stress of the brush bristles, resulting in a microgroove structure. This structure was confirmed through scanning electron microscopy analysis, which revealed the clear presence of rGO. Comparing the electrical properties of a zirconium bismuth indium oxide thin film without graphene oxide doping and a thin film doped with 15 wt% graphene oxide, the electro-optical properties were significantly improved with graphene oxide doping. In general, the threshold voltage decreased by approximately 0.42 V. In addition, bandgap measurements confirmed the improved conductivity characteristics with graphene oxide doping. Since this improvement in electro-optical properties is associated with the reduction process due to graphene oxide doping, X-ray photoelectron spectroscopy analysis was performed to assess the intensity change of each element. Based on these observations, hybrid thin films doped with graphene oxide emerge as promising candidates for next generation thin film.

The Influence of Thickness and Spectral Properties of Green Color-Emitting Polymer Thin Films on Their Implementation in Wearable PLED Applications.

A systematic investigation of optical, electrochemical, photophysical, and electrooptical properties of printable green color-emitting polymer (poly(9,9-dioctylfluorene-alt-bithiophene)) (F8T2) and spiro-copolymer (SPG-01T) was conducted to explore their potentiality as an emissive layer for wearable polymer light-emitting diode (PLED) applications. We compared the two photoactive polymers in terms of their spectral characteristics and color purity, as these are the most critical factors for wearable lighting sources and optical sensors. Low-cost, solution-based methods and facile architecture were applied to produce rigid and flexible light-emitting devices with high luminance efficiencies. Emission bandwidths, color coordinates, operational characteristics, and luminance were also derived to evaluate the device's stability. The tuning of emission's spectral features by layer thickness variation was realized and was correlated with the interplay between H-aggregates and J-aggregates formations for both conjugated polymers. Finally, we applied the functional green light-emitting PLED devices based on the two studied materials for the detection of Rhodamine 6G. It was determined that the optical detection of the R6G photoluminescence is heavily influenced by the emission spectrum characteristics of the PLED and changes in the thickness of the active layer.

The Effect of Thickness on Some Optical Properties of Sb2S3 Thin Films Prepared by Chemical Bath Deposition

Sb2S3 thin films have been prepared by chemical bath deposition on a glas sub Absorbance and transmittance spectra were recorded in the wavelength range (30-900) nm. The effects of thickness on absorption coefficient, reflectance, refractive index, extinction coefficient, real and imaginary parts of dielectric constant were estimated. It was found that the reflectivity, absorption coefficient , extinction coefficient, real part of dielectric constant and refractive index, all these parameters decrease as the thickness increased, while the imaginary part of the dielectric constant increase as the thickness increased.

Structural and Optical Properties of Cobalt-Doped Zinc Oxide Thin Films Prepared By Spray Pyrolysis Technique

Undoped and Co-doped zinc oxide (CZO) thin films have been prepared by spray pyrolysis technique using solution of zinc acetate and cobalt chloride. The effect of Co dopants on structural and optical properties has been investigated. The films were found to exhibit maximum transmittance (~90%) and low absorbance. The structural properties of the deposited films were examined by x-ray diffraction (XRD). These films, deposited on glass substrates at (400? C), have a polycrystalline texture with a wurtzite hexagonal structure, and the grain size was decreased with increasing Co concentration, and no change was observed in lattice constants while the optical band gap decreased from (3.18-3.02) eV for direct allowed transition. Other parameters such as Texture Coefficient (Tc), dislocation density (?) and number of crystals (M) were also calculated .

Exploring the impact of thin film thicknesses on the linear and nonlinear optical properties of ZrO2 thin film

Exploring the impact of thin film thicknesses on the linear and nonlinear optical properties of ZrO2 thin film

Low-temperature growth of CuS thin film on flexible substrates for photodetection

Abstract The covellite phase of copper sulfide thin film (CuS), owing to its excellent electronic, optical, and chemical properties, has attracted enormous attention in cutting-edge research. This research work emphasizes a comprehensive study of structural, optical, morphological, and electrical properties of CuS thin film deposited by chemical bath deposition (CBD) technique on flexible polyethylene terephthalate (PET) substrate at different deposition temperatures, i. e. 25 °C, 40 °C, 55 °C, and 70 °C for fabrication of flexible photodetector. XRD and Raman studies depict presence of hexagonal covellite phase (CuS), where as the RMS roughness of CuS thin film increases with a rise in deposition temperature. The optical bandgap of CuS thin film gets reduced with a rise in deposition temperature. The optimized CuS thin film, deposited at 70 °C, has exhibited a homogeneous surface with RMS roughness of 13.72 nm, mobility of 25.09 cm2/Vs, and bandgap of 1.86 eV. The mobility of CuS thin film is found to be increased with the rise in deposition temperature. The flexible CuS photodetector, deposited at 70 °C, has shown better photoresponse characteristics, exhibiting the highest responsivity of 0.18 mA/W, detectivity of 1.39×108 Jones, and sensitivity of 173.25 % upon light illumination. The photocurrent established possesses an outstanding dependence on various intensities of illuminated light. Furthermore, the bending test of flexible CuS photodetectors reveals the absence of any sign of deterioration up to a bending angle of 30°. The CuS thin film-based photodetector device exhibits the optimized photodetector device with reproducibility and steady photoresponse after bending. This suggests that the Al/CuS-PET/Al photodetector device could be used in various wearable optoelectronic device applications.

Synthesis and properties of superhydrophobic monomer stearyl methacrylate-modified polyacrylate latex pressure sensitive adhesives

Hybrid surfactants of long carbon chain hydrophobic nonionic emulsifier N-390 and conventional anionic emulsifier CO-436 were utilized in this study to enable successful emulsion polymerization of super-hydrophobic monomer stearyl methacrylate (SMA) together with butyl acrylate (BA), acrylic acid (AA), and 2-hydroxyethyl acrylate (HEA). The influences of SMA on the resulting latex and film properties were thoroughly investigated. Both FTIR and 1H NMR were used to confirm the successful participation of SMA in the emulsion polymerization. The results indicated that with introduction of SMA, the roughness of the latex film increases, while the light transmission decreases. It was also found that with the addition of SMA, contact angle of the latex PSA film increased from 115.1° to 127.2°, while water absorption decreased from 5.76 to 2.89 wt%. DSC curves demonstrated that SMA has participated more in the homopolymerization reaction than in the copolymerization reaction. TGA results showed that the initial decomposition temperature (T5%) of the latex film was increased from 302.8 to 332.7 °C with the increase of SMA dosage from 0 to 20 wt%. Finally, adhesion properties results indicated that loop tack and 180° peel force of the PSA films were decreased from 11.51 to 1.88 N/25 mm and 6.36 to 3.44 N/25 mm, respectively, while shear strength was increased from 732 to 2865 min.

Synthesis of chemical bath deposited Manganese oxide thin films for high performance supercapacitor

The present study addresses the growing need for high-performance supercapacitors, emphasizing the benefits of Manganese oxide (MnO2) thin film as a promising electrode material. Thin film deposition of MnO2 is achieved through Chemical Bath Deposition (CBD) method by varying the deposition time on the stainless steel substrate. In order to investigate impact of deposition time on various physico-chemical properties of MnO2 thin films, different characterizations were carried out like X-ray diffraction, Scanning electron microscopy, Energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, cyclic voltammetry, Galvanostatic charge–discharge analysis. The deposited MnO2 thin films are subsequently studied for their electrochemical properties in a 1 M KOH electrolyte solution. Remarkably, the best specific capacitance is obtained about 296.5 F/g at current density of 0.5 A/g, with 86.42 % retention after 5000 cycles, highlighting the excellent electrochemical performance of the MnO2 thin films deposited at 6 hrs of reaction time. This work highlights valuable insights into the CBD deposited MnO2 thin films for supercapacitor applications, providing a foundation for the development of an efficient, low-cost, and scalable energy storage devices.

The influence of precursor solutions containing an amount of silver bismuth sulfide nanoparticles (AgBiS2 NPs) on the characteristics of CH3NH3PbI3 perovskites solar cells

The utilization of organo-metal halide perovskites as absorbers in thin-film solar cells has garnered considerable interest from the scientific community in recent times. In this study, we present the introduction of silver bismuth sulfide nanoparticles (AgBiS2 NPs) doped into perovskite thin films composed of CH3NH3PbI3 thin film. Our results demonstrate that the perovskites' morphology and structure were significantly improved. The effects of AgBiS2 NPs concentration on the optical, mechanical, and crystallographic properties of CH3NH3PbI3 perovskite thin films were investigated. The findings from the structure investigations revealed that an increase in the concentration of AgBiS2 NPs resulted in a transition from a low-crystalline to a polycrystalline structure of the perovskite thin films. An elevation in the concentration of AgBiS2 NPs from 2 to 8 mg/mL led to the development of perovskite films of superior quality, consisting entirely of PbI3 and CH3NH3. These films exhibited almost impeccable deposition, compactness, and uniformity, and their particle size reached an approximate value of 1.3 μm. Furthermore, an increase in the optical absorption coefficient (∼105 cm−1) in the visible spectrum and subsequent enhancements in photoluminescence (PL) and ultraviolet–visible (UV–Vis) absorption spectroscopy serve as further evidence of the film's enhanced quality. When AgBiS2 NPs are doped into perovskites, the films' quality is significantly improved; they acquire a uniform surface morphology, an exceptional crystal structure, and enhanced light absorption, all of which contribute to accelerated PL quenching and charge transfer. Power conversion efficiency (PCE) was enhanced across all photovoltaic parameters through the use of larger granules in bulk-heterojunction solar cells, as opposed to undoped heterojunction solar cells. The PCE of the perovskite device with CH3NH3PbI3 base is 17.04 % at the optimal concentration of 6 mg/mL AgBiS2 NPs. These findings indicate that the doping of CH3NH3PbI3 perovskite thin films with AgBiS2 NPs is essential for the achievement of high crystallinity, a large particle size, and a high absorption coefficient. These properties are advantageous for the high-power conversion efficiency of solar cell applications.

Excellent facile fabrication of PVA and lignin nanoparticles from wheat straw after novel DES-THF pretreatment

The utilization of environmental friendly and renewable materials has received increasing attention recently. Lignin nanospheres (LNPs) prepared from recovered lignin and residual lignin after DESs and DESs-THF pretreatment were obtained by self-assembly in the present research. Then, films were prepared by incorporating them into polyvinyl alcohol (PVA) solution. The properties of various films were characterized and compared. Results showed that as the LNPs content increased, the UV blocking capacity of the films was gradually enhanced than PVA film. The DES-THF films showed better antioxidant properties up to 69 % due to higher phenolic hydroxyl content. The hydrophobicity of films incorporated with DESs-THF pretreated lignin was consistently better than that of DES pretreated. DES-THF-M films showed a higher Tmax than that of DES-M films, resulting in better thermal stability. Moreover, DES-THF-L films are lighter in color due to a lower degree of condensation, which is favorable to subsequent applications. The incorporation of LNPs improved mechanical and antioxidant properties, thermal stability, and UV shielding ability of PVA films, especially lignin after DES-THF pretreatment. In conclusion, the prepared PVA/LNPs composite films possessed good functional properties that make them potential for packaging materials.

Micromechanical Characterization of AlCu Films for MEMS Using Instrumented Indentation Method.

The micromechanical properties (i.e., hardness, elastic modulus, and stress-strain curve) of AlCu films were determined by an instrumented indentation test in this work. For three AlCu films with different thicknesses (i.e., 1 µm, 1.5 µm, and 2 µm), the same critical ratio (hmax/t) of 0.15 and relative indentation depth range of 0.15-0.5 existed, within which the elastic modulus (i.e., 59 GPa) and nanoindentation hardness (i.e., 0.75 GPa, 0.64 GPa and 0.63 GPa for 1 µm, 1.5 µm and 2 µm films) without pile-up and substrate influence can be determined. The yield strength (i.e., 0.754 GPa, 0.549 GPa and 0.471 GPa for 1 µm, 1.5 µm and 2 µm films) and hardening exponent (i.e., 0.073, 0.131 and 0.150 for 1 µm, 1.5 µm and 2 µm films) of Al-(4 wt.%)Cu films for MEMS were successfully reported for the first time using a nanoindentation reverse method. In dimensional analysis, the ideal representative strain εr was determined to be 0.038. The errors of residual depth hr between the simulations and the nanoindentation experiments was less than 5% when the stress-strain curve obtained by the nanoindentation reverse method was used for simulation.

Impact of environmental storage conditions on properties and stability of a smart bilayer film

This study aimed to investigate the behavior of smart bilayer films under various temperature and relative humidity (RH). Smart bilayer films were fabricated using sodium alginate with incorporated butterfly pea anthocyanin and agar containing catechin–lysozyme. Cellulose nanospheres were added at concentrations of 0% and 10% w/w of the film and subjected to test at 4 °C and 25 °C, considering different RHs (0%, 50%, and 80%). The results showed that RH had a greater impact on the mechanical properties than temperature, leading to a decrease in tensile strength and an increase in elongation at break with higher RH. The films displayed increased strength but reduced flexibility at low temperatures. Oxygen permeability was negatively affected by increasing RH, while water vapor barrier properties were better at 25 °C than at 4 °C. In terms of color stability, the temperature played a more important role, with both types of smart bilayer films retaining their color stability throughout 14-day storage at 4 °C, even maintaining their ability to change color with pH. However, the films stored at 25 °C exhibited lower color stability and showed potential for color change with varying pH levels, but with lower intensity. The findings of this study demonstrate the significant impact of temperature and RH on the functional properties of smart bilayer films, with and without the addition of cellulose nanospheres. Such smart bilayer films have great potential for various applications, particularly in food packaging, where maintaining color, mechanical, and barrier properties under varying environmental conditions is crucial.

Effect of surface electromagnetic wave treatment on the refractive properties of thin films based on indium tin oxides with laser-deposited single-walled carbon nanotubes

Effect of surface electromagnetic wave treatment on the refractive properties of thin films based on indium tin oxides with laser-deposited single-walled carbon nanotubes