Effect Of Deposition Time Research Articles

A Green Approach to Modify Surface Properties of Polyurethane Foam for Enhanced Oil Absorption.

The non-selective property of conventional polyurethane (PU) foam tends to lower its oil absorption efficiency. To address this issue, we modified the surface properties of PU foam using a rapid solvent-free surface functionalization approach based on the chemical vapor deposition (CVD) method to establish an extremely thin yet uniform coating layer to improve foam performance. The PU foam was respectively functionalized using different monomers, i.e., perfluorodecyl acrylate (PFDA), 2,2,3,4,4,4-hexafluorobutyl acrylate (HFBA), and hexamethyldisiloxane (HMDSO), and the effect of deposition times (1, 5 and 10 min) on the properties of foam was investigated. The results showed that all the modified foams demonstrated a much higher water contact angle (i.e., greater hydrophobicity) and greater absorption capacities compared to the control PU foam. This is due to the presence of specific functional groups, e.g., fluorine (F) and silane (Si) in the modified PU foams. Of all, the PU/PHFBAi foam exhibited the highest absorption capacities, recording 66.68, 58.15, 53.70, and 58.38 g/g for chloroform, acetone, cyclohexane, and edible oil, respectively. These values were 39.19–119.31% higher than that of control foam. The promising performance of the PU/PHFBAi foam is due to the improved surface hydrophobicity attributed to the original perfluoroalkyl moieties of the HFBA monomer. The PU/PHFBAi foam also demonstrated a much more stable absorption performance compared to the control foam when both samples were reused for up to 10 cycles. This clearly indicates the positive impact of the proposed functionalization method in improving PU properties for oil absorption processes.

The Effect of Deposition Time on the Voltage Range and Sensitivity of Cu/Ni as Low-Temperature Sensor Resulted from Electroplating Assisted by a Transverse Magnetic Field

The Cu/Ni thin film as low-temperature sensor was produced by electroplating on the various deposition times assisted with a 200G magnetic field in the transverse direction to the surface of Cu. The deposition time was varied from 0 to 45s. The liquid nitrogen (LN2) 0°C to -200°C was used as a tested low-temperature medium. The characterization was done on the voltage range and sensitivity. Cu/Ni sensor from deposition within 25s has the largest voltage range that is 128.48 mV and has the sensitivity (S) that has a linear relationship with temperature (T) according toS(T) = 0.287 - 0.002T.

The Effect of Deposition Time on the Surface Coverage of Sublimation Deposited Solid-Phase Glycine and Proline Molecules Measured by Scanning Tunneling Microscopy.

The effect of deposition time on the surface coverage of sublimation deposited solid-phase glycine and proline molecules onto a Ge(100) surface was studied at room temperature using scanning tunneling microscopy (STM). The STM images obtained at various coverages of glycine and proline adsorbed on the Ge(100) surface showed that (i) the adsorption rate for both molecules gradually decreased with increasing deposition time, obeying the Langmuir adsorption model, and (ii) the coverage of glycine on the Ge(100) surface is higher than that of proline under the same deposition conditions, which may be due to the differences in their molecular weight or molecular sticking probability.

Studying the effect of deposition time on physical properties of CdTe thin films; Influence of CdTe electrical properties on CdS/CdTe heterojunction rectifying behavior

CdTe nanostructured thin films were grown on glass substrates by RF-magnetron sputtering at different deposition time periods (10, 20 and 30 min). The layers were characterized by FESEM, EDAX, XRD, Raman, UV–vis., PL spectra, also Seebeck effect and I–V-T measurements. It is found with increasing the deposition time: the size of cubic phase CdTe nano-grains were gradually increased and the stoichiometry of the layers improved, as consistent with the PL spectra of layers. The synthesized CdTe layers were then put in contact with an optimized CdS layer. The analysis of dark I–V data showed that the electrical properties of CdTe layer has crucial impact on rectifying ration (RR) of the prepared CdS/CdTe heterojunction diodes.

The film thickness effect on the physical properties of NiO thin films elaborated by Sol-gel method

In this work, nickel oxide (NiO) was elaborated on glass substrate at by sol-gel technique. The NiO thin films were prepared with 0.8 M Ni(NO3)2 6H2O annealed at 600 °C for 2 h. The coating process was repeated for 13, 14, 15, 16 and 17 times to obtain a thin film, which corresponded to 124, 137, 143, 147 and 166 nm of film thickness. NiO thin films were observed as nanocrystalline with cubic structure at 166 nm with (111) and (200) peaks were observed. All NiO thin films have an average transmittance of about 80 % in the visible region. The NiO thin films have a variety in the band gap energy from 3.87 to 3.94 eV. Because of the effect of deposition times, the minimum value was found at 166 nm where this condition has the highest Urbach energy. The NiO thin films have an electrical conductivity which was increased from 7.94 x10-3 to 84x10-3 (Ω.cm)-1 when film thickness increases from 124 to 137 nm. In the end, the electrical measurements were investigated by the four-point method, with the results show good electrical conductivity at 166 nm.

Effect of deposition time on structural and optical properties of ZnSe thin films grown by CBD method

Undoped ZnSe thin films were prepared using Chemical bath deposition method (CBD). All samples were deposited on glass substrates in acidic solution at 80 °C for 60, 120, 180 and 240 min. The effect of deposition time on the structural and optical properties of ZnSe thin layers were investigated by X-Ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, atomic force microscopy (AFM), UV–Vis and photoluminescence (PL) spectroscopies. XRD patterns of the deposited thin films exhibited cubic structure with a preferred (111) orientation. The crystal quality and the average crystallite size were found to increase at higher durations of deposition. FTIR spectrum confirmed the presence of ZnSe vibration band. AFM analysis revealed that both of morphology and surface roughness were affected by time of deposition. According to UV–Vis results, all samples were transparent with average visible transmission values ranging from 55% to 72%. The optical band gap was found to decrease with increasing deposition time. The room temperature PL spectra indicated the presence of three emissions at 460, 575 and 630 nm.

Enhancement of Cu(In,Ga)Se2 solar cells efficiency by controlling the formation of Cu-deficient layer

The effects of deposition time of the second stage (t2nd) and the third stage (t3rd) during the three-stage process on the formation of Cu-deficient layers (CDLs) at Cu(In,Ga)Se2 (CIGS) near-surface were investigated in this study. The experimental findings suggested that the CDL was thickened by a longer deposition time in the third stage. Also, the device performance was found to deteriorate with the increased thickness of CDLs, suggesting that the CDL has a defect concentration higher than that of CIGS thin films. Furthermore, the peak position of electron beam induced current signal was shifted towards the interior region of CIGS films, confirming the n-type conductivity of CDLs. The highest conversion efficiency of 19.0% was obtained in this work when the thickness of CDL was 80 nm.

Characterization of thin film of CuO nanorods grown with a chemical deposition method: a study of significance of deposition time

In this study, vertically aligned copper oxide (CuO) nanorods were grown on indium tin oxide substrate using chemical bath deposition as a facile and economical method. The effect of deposition times on the morphological, structural, optical, and electrical properties of CuO nanorods was investigated. X-ray diffraction analysis confirmed one-dimensional growth of CuO nanorods along the preferred plane of (002). Field emission scanning electron microscopy analysis revealed the growth of vertically aligned nanorods for all deposition times. It was observed that the length of nanorods and UV–vis absorption of the CuO thin films was increased with duration of growth. Current-voltage response of the samples was investigated and the results showed a linear behavior for all samples. Electrical resistance of nanorods was also measured. The results showed that the electric resistance decreases with increasing the growth time up to 90 min and it increases afterwards.

Characterization of gold nanoparticle thin film prepared by electrophoretic deposition method

Gold nanoparticle thin films were deposited on copper substrate using electrophoretic deposition (EPD) method. At first, gold nanoparticles were synthesized, using pulsed laser ablation method of a high-purity gold target in distilled water. Ablation was carried out, employing the fundamental wavelength of a Q-switched Nd:YAG laser at 1064 nm and pulse width of 7 ns. Suspension of gold nanoparticle was used as the electrolyte of EPD, in which two copper electrodes with 7 mm gap were immersed. Five samples of gold nanoparticle thin films were prepared at different deposition times and applied voltages. Nanoparticles and thin films were characterized by different diagnostics such as X-ray diffraction pattern, atomic force microscopy (AFM), and scanning electron microscopy (SEM) images as well as optical spectroscopy. XRD pattern determined crystalline structure of gold thin films. SEM image showed the effect of deposition time and applied voltage on the morphology of deposited films. AFM results demonstrated the variations in roughness, thickness, and surface quality due to changes in applied voltage and deposition time. Also, the optical properties of thin films were studied by UV-vis reflection spectroscopy.

The effects of deposition time and current density on the electrochemical performance of flexible and high-performance MnO2@PFG composite electrodes.

A novel composite electrode has been fabricated by the direct deposition of MnO2 onto graphene networks surrounding a paper fiber (PFG). The paper fiber between graphene sheets could be used as a flexible substrate for MnO2 nanoparticles, and the microscopic morphologies and electrochemical performances of the MnO2@PFG electrodes were tuned via regulating the deposition current densities and deposition times. 3D graphene on PFG served as a highly conductive backbone with a high surface area for the deposition of the MnO2 nanoparticles, which provided high accessibility to electrolyte ions for shortening the diffusion paths. The MnO2-10-600 s@PFG composite electrode achieved a maximum specific capacitance of 878.6 mF cm−2 with an MnO2 loading mass of 3.62 mg cm−2 (specific capacitance of 187.7 F g−1) at a current density of 0.5 mA cm−2 in a 1 M NaSO4 aqueous solution. Additionally, the MnO2-10-600 s@PFG composite material with the most favorable composite ratio exhibited the highest energy density of 61.01 mW h cm−2, maximum power density of 1249.78 mW cm−2, excellent capacitance retention with no more than 7% capacitance loss after 10 000 cycles and good mechanical flexibility (about 91.06% of its original capacitance after 500 bending times). By combining the electric double layer capacitance of graphene networks with the pseudocapacitance of the MnO2 nanostructures, the flexible electrode showed much enhanced electrochemical capacitance behaviors with robust tolerance to mechanical deformation; thus, it is promising for being woven into textiles for wearable electronics.

Room Temperature Synthesized TiO2/Bi2Se3 Bilayer Thin Film by Simple Chemical Route: Study the Effect of Deposition Time of Bismuth Selenide on Physical Properties of Film

Room Temperature Synthesized TiO2/Bi2Se3 Bilayer Thin Film by Simple Chemical Route: Study the Effect of Deposition Time of Bismuth Selenide on Physical Properties of Film

Effect of Deposition Time of Mn on Photoelectrochemical Properties of Mn/TiO2 Nanotubes

Coupling of TiO2 nanotube arrays (NTAs) with narrow band gap materials has been a promising strategy to extend the absorption of TiO2 into visible light region. In this work, the fabrication of manganese doped TiO2 nanotube arrays (Mn/TiO2 NTAs) was carried out by an electrodeposition method. The deposition time of Mn onto TiO2 NTAs which was varied in the range of 1-5 minutes was found to play an important role in controlling the formation and distribution of Mn nanoparticles onto TiO2 NTAs. The films were characterized by field emission scanning electron microscopy (FESEM), X-ray diffractometry (XRD), energy dispersive X-ray spectroscopy (EDX) and UV–vis diffuse reflectance spectroscopy to determine their morphology, crystalline structure, and optical properties of the samples. The results from FESEM showed that Mn nanoparticles were found to grow larger and cause blockage to the mouth of the nanotubes with prolongs deposition time. On the other hand, Mn/TiO2 NTAs synthesized with shorter deposition time exhibits significant enhancements in the optical absorption and photocurrent density. In particular, the Mn/TiO2 NTAs produced at 1minute deposition time exhibited the highest photocurrent density compared to the others. The uniform distribution and quantity of the Mn could be the reason for this performance, therefore, more light was absorbed and generating more electron-hole pairs then giving the highest photocurrent.Â

Antibacterial activity of ZnO nanoflowers deposited on biodegradable acrylic acid hydrogel by chemical bath deposition

In the first part of this study, acrylic acid (AA) hydrogels were produced by a free radical reaction. Chemical and morphological structures of AA-hydrogels were specified by using Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) techniques. In the second part of the study, ZnO nanoflowers were synthesized on the AA-hydrogel by using a chemical bath deposition (CBD) technique for the first time in the literature. The AA-hydrogel acted as the substrate in the CBD process. The deposition time effect on the morphological properties of ZnO nanoflowers was determined by applying SEM. According to the SEM results, the deposition time in the production of ZnO nanoflowers has played a vital role in the surface morphology. Chemical, morphological and thermal properties of the ZnO nanoflowers were determined by applying FT-IR, scanning electron microscopy-energy dispersive X-ray spectroscopy and thermogravimetric analysis techniques. Elemental mapping of ZnO nanostructures was carried out using SEM. The antibacterial activity of the ZnO nanoflower-deposited AA-hydrogel was determined against Gram-negative and Gram-positive bacteria. Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were used as test microorganisms. Gram-negative bacteria were more resistant to hydrogels and ZnO nanoflowers compared to Gram-positive bacteria.

Effect of Deposition Time on Structural, Morphological and Optical Properties of PVA Capped SnS Films Grown by CBD Process

In this study, the effect of deposition time on physical properties of tin monosulphide films capped by polyvinyl alcohol was investigated. Chemical bath deposition technique was used to deposit Polyvinyl alcohol capped SnS films on cleaned glass substrates and the deposition was carried out at four different times varying from 45 to 90 min. The X-ray diffraction study revealed that the deposited layers were polycrystalline in nature with (040) as the preferred plane. Single phase SnS was observed in the layers grown at a deposition time of 90 min while the other layers had secondary phases of Sn and S. The XRD data was also used to determine various parameters such as crystallite size, dislocation density, lattice strain, stacking faults and inter planar spacing. Raman measurements exhibited same structural phases, consistent with the XRD observations. The surface morphology of the layers was initially uneven and become uniform at 90 min deposition time. Fourier transform infrared spectra, confirmed the presence of SnS and PVA in the films. Optical studies revealed high optical absorption coefficient for all the films with a shift in optical band gap value compared with the bulk value.

Optimization of physicochemical and optical properties of nanocrystalline TiO2 deposited on porous silicon by metal-organic chemical vapor deposition (MOCVD)

Titanium dioxide (TiO2) is very employed in solar cells due to its interesting physicochemical and optical properties allowing high device performances. Considering the extension of applications in nanotechnologies, nanocrystalline TiO2 is very promising for nanoscale components. In this work, nanocrystalline TiO2 thin films were successfully deposited on porous silicon (PSi) by metal organic chemical vapor deposition (MOCVD) technique at temperature of 550 °C for different periods of times: 5, 10 and 15 min. The objective was to optimize the physicochemical and optical properties of the TiO2/PSi films dedicated for photovoltaic application. The structural, morphological and optical properties of the elaborated TiO2/PSi samples were analyzed by means of x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX), atomic force microscopy (AFM), photoluminescence (PL) and UV-Visible absorption spectroscopy methods. The effect of deposition time on the microstructural properties which influences the optical characteristics of the obtained samples was also examined. The XRD analysis confirms the nanocrystalline structure of the deposited TiO2 composed only by anatase phase. The SEM characterization evidenced an increase in the TiO2 film thickness showing more uniform surfaces as the deposition time rises. Correspondingly, the surface roughness increases with the particle size and film thickness as indicated by AFM studies. The TiO2/PSi/Si sandwich structure evidenced by cross-sectional SEM confirms the good adherence of the TiO2 nanocrystalline film on the porous silicon forming with silicon a composite material. The UV-Vis measurements showed a considerable enhancement in optical absorption of porous silicon after the deposition of TiO2 films. Indeed, the TiO2 coatings deposited on PSi for 15 min with thickness of 200 nm have the best structure quality and exhibit, consequently, the highest absorption. From these interesting results, we demonstrate the viability of the use of the MOCVD as reproducible process for the elaboration of high-quality TiO2/PSi films.

Effect of Deposition Time and Temperature on Structural, Topographic and Optical Properties of Nano (ZnS) Film Prepared by CBD Technique

The research includes the study of the effect of some preparing factors (time of deposition and temperature) on structural, topographic and optical properties of zinc sulfide (ZnS) nanoscale film. Nanofilms prepared by using a chemical bath deposition .The compositional properties included: pictures of X-ray diffraction (XRD), also included the topographic characteristics: pictures of the optical microscope (ORM) and pictures of the atomic force microscope (AFM), while the included optical properties: transmittance, absorption coefficient, the optical energy gap. The results of X-ray examinations (X-ray) to prepare films by (CBD) method have amorphous structure. It has been observed that increasing the time of deposition led to decrease values ​​of the forbidden energy gap, while it was observed that the increase in temperature led to a increase in the values ​​of the forbidden energy gap .

Sensitization of TiO2 by chemically deposited Cu2S for solar cell: Effect of deposition time on photoelectrochemical performance

In present investigation we have demonstrated Copper Sulphide (Cu2S) as an alternative light harvester for photoelectrochemical (PEC) application. A low-cost chemical route namely chemical bath deposition (CBD) method is efficiently employed for deposition of Cu2S nanoparticles over spin coated porous Titanium Dioxide (TiO2) films. Deposition time in CBD facilitates size tuning of Cu2S nanoparticles on TiO2 which influence the photoelectrochemical response and ultimately on photo conversion efficiency of device. The XRD study confirmed the formation of Cu2S nanoparticles on TiO2. The optical and surface morphological properties further confirm the formation of TiO2/Cu2S architecture and are systematically presented. The photovoltaic properties of Cu2S sensitized TiO2 solar cells are evaluated by constructing FTO/TiO2/Cu2S/polysulphide/carbon coated FTO device structure. The behaviour of electron in the device was study by electrochemical impedance spectroscopy (EIS) measurement. Furthermore, the J-V curve of TiO2/Cu2S hetrostructure photoanodes is used to measure the photo conversion efficiency and the maximum efficiency of 0.193 % is recorded under illumination of simulated sunlight at 50 mW/cm2 condition with maximum electron life time of 34 ms for 2 h deposited Cu2S.

Electrophoretic deposition of cobalt oxide nanoparticles on aluminium substrate

ABSTRACT In the present work, the effects of deposition time and applied voltage on the quality of cobalt nanoparticle film, deposited on aluminium substrate have been investigated experimentally. Cobalt oxide nanoparticles were produced by laser ablation method. The produced nanoparticles were deposited on aluminium substrate with electrophoretic deposition technique at different applied voltage and deposition time. Produced nanoparticles as well as deposited films were characterized by employing several diagnostics including scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffractometry (XRD), and UV–Vis–NIR spectroscopy. XRD pattern confirmed the presence of the cobalt oxide in all samples. SEM micrographs showed the effective role of applied voltage and deposition time on the morphology of deposited films. By using AFM results roughness, thickness and average particles size of deposited films were measured. Also an optimum point for applied voltage and deposition time were investigated. UV–Vis–NIRspectroscopy determined optical properties of nanoparticles and deposited films.

High-performance solid-state supercapacitors with designable patterns based on used newspaper

From the viewpoint of developing low-cost, eco-friendly and flexible energy storage devices, the used newspaper that consists of interconnected cellulose fibers was served as flexible substrate to fabricate solid-state supercapacitors. Graphite current collectors with desired patterns were directly coated on the used newspaper by pencil drawing and then three dimensional interconnected polypyrrole nano/microcones were electrochemically deposited on them, forming the newspaper-based graphite–PPy nano/microcones (NGP) electrodes. The effect of deposition time on the morphology and electrochemical properties of the NGP electrodes was investigated. The NGP electrode that obtained by electrochemical polymerization of pyrrole for 120 min showed a high specific capacitance of 1122 mF cm−2 (1 mA cm−2). Solid-state supercapacitors based on NGP electrodes with a sandwich structure and in-plane interdigital structure were fabricated, which exhibited excellent specific capacitance, energy density, power density, flexibility and voltage/current scalability. Other electrodes/supercapacitors with designable patterns also can be obtained by this simple method. These results indicate the NGP-based supercapacitors are promising in diverse portable and flexible electronics.

A Schiff base modified graphene oxide film for anodic stripping voltammetric determination of arsenite.

A protocol is described for chemical modification of graphene oxide with a Schiff base derived from diethylenetriamine and 2-hydroxy-4-methoxybenzophenone. The base was grafted onto an indium tin oxide (ITO) film and applied to electroanalytical determination of arsenite. Successful grafting was confirmed by Fourier transform-infrared spectroscopy, spectrophotometry, field emission scanning electron microscopy and cyclic voltammetry. Secondly, the coated ITO film served as a working electrode for the stripping voltammetric determination of arsenite. The analytical signal is generated by selective oxidation of metal species via multi-donor sites present in the derivatized Schiff base. The electroanalytical protocol was optimized by investigating the effects of deposition time, working potential, frequency and amplitude of square wave anodic stripping voltammetry. The method has attractive features including (a) the usage of a non-metallic, non-toxic and cost-effective material; (b) improved sensitivity (with limit of detection as low as 156 pM) due to better adsorption of arsenite in the Schiff base pockets on the ITO, and (c) the application to the determination of arsenite in real samples. Graphical abstract Schematic representation of the fabrication of a Schiff base-functionalized graphene oxide on an indium tin oxide (SB@SiO2@GO@ITO) electrode for selective electrochemical sensing of arsenite due to adsorption on multi-donor sites.