Effect Of Bath Temperature Research Articles

Effect of bath temperature and annealing on the formation of CuInSe 2

CuInSe 2 films of 2 μm thickness were electrodeposited potentiostatically, from aqueous solution containing thiocyanate as a complexing agent, on Mo substrates. For all the experiments, the potential of the potentiostatic deposition of the materials was chosen to be −1 V, whereas the bath temperature of electrolyte was varied from 20 to 80 °C. It was found that the electrodeposited CuInSe 2 was characterized by an amorphous layer and densely-packed nanometric grains with a good homogeneity. After vacuum annealing at 200 °C, glancing angle X-ray diffraction revealed the presence of the CuInSe 2 phase whereas annealing under selenium atmosphere lead to the growth of molybdenum selenide compound MoSe 2, in addition to a better crystallization of the copper indium diselenide compound. Scanning electron microscopic revealed that despite an increase in the grains dimensions, there was no significant change in the films surface morphology when the bath temperature was varied from 20 to 80 °C. At the same time, the composition of the electrodeposited Cu–In–Se layers becomes richer in copper. This increase in copper concentration is mainly compensated by a deficit in selenium atoms.

Electrocrystallization of Hydroxyapatite and Its Dependence on Solution Conditions

Electrocrystallization of hydroxyapatite (HAp) on titanium was achieved by cathodic polarization in solution containing calcium nitrate and ammonium dihydrogen phosphate. The composition and pH of the bath were found to significantly affect the nature and surface morphology of the deposit. The effect of bath temperature was also studied. X-ray diffraction tests and microscopic inspections confirmed the formation of well-crystallized HAp at pH0 = 6.0 at any temperature between 70 and 95 °C, whereas, at pH0 = 4.2, less-crystallized, thicker, and more porous coatings that contained traces of octacalcium phosphate were observed. The influence of potassium chloride and sodium nitrite on the composition and surface morphology of the deposit was also evaluated. A speciation−precipitation model was applied to better understand the effect of bath conditions. The standard enthalpy of activation was ∼40 kJ mol−1, indicating that the reaction kinetics is controlled by the interfacial area. The corrosion resistance of...

The effect of bath temperature on the electrodeposition of zinc oxide thin films via an acetate medium

The temperature-dependent nucleation and growth mechanism of electrodeposited zinc oxide (ZnO) thin films on fluorine-doped tin-oxide-coated (10–20 Ω cm−2) glass substrates from an acetate solution was studied by using the chronoamperometry technique. The morphological, compositional and structural properties were studied by scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and x-ray diffraction techniques. The current transients were analyzed by fitting chronoamperometric data into the Scharifker–Hills nucleation model, which reveals a change in the nucleation and growth mechanism from progressive to intermediate (progressive + instantaneous) to instantaneous with a rise in bath temperature (from 25 °C to 75 °C). The SEM study showed hexagonal grains for the films obtained at 35 °C. The x-ray diffraction spectra revealed the formation of phase-pure ZnO thin films. The chemical state of the deposit was confirmed by XPS measurements.

Effects of process parameters on the synthesis of palladium membranes

In this study, palladium film plating was carried out on porous glass supports using the electroless plating technique. This technique was applied to study the effects of bath temperature and reducing agent concentration on the amount and the structure of palladium plated. Hydrazine concentration was fixed at 10 ml/L in the baths using 1 M hydrazine solution while the temperature was changed between 25 and 50 °C. The total mass gain and Pd/Si ratio (wt/wt%) on the surface were obtained as 7.76 mg/cm 2 and 68.7 in a bath temperature of 35 °C, respectively. With the help of LM microscope analysis, thickness of the membrane prepared at this temperature was determined as 31 μm. In the studies in which the bath temperature was examined as a parameter, the minimum total mass gain was obtained in a plating bath temperature of 43 °C. In the second part of this study, in order to study the concentration effect of hydrazine, hydrazine concentration was increased to 15 and 20 ml/L at a bath temperature of 43 °C. It was shown that as a result of increasing the hydrazine concentration from 10 ml/L to 15 ml/L, total mass gain increased more than twice and a denser plating was obtained. On the contrary to expectations, a result less successful than in the study of 10 ml/L concentration was obtained through increasing hydrazine concentration to 20 ml/L. This study showed that bath temperature of 25 °C was too low to carry out effectively autocatalytic reaction on the activated surface. Plating bath decomposed in plating studies performed at 43 °C and 50 °C. In the studies where hydrazine concentrations were examined as a parameter, it was observed that the stability of the bath could not be maintained in each of the three baths throughout the plating time. The highest decomposition rate was also predicted for the study carried out at a hydrazine concentration of 20 ml/L. Decomposition seen at high temperatures and high hydrazine concentrations was explained as a consequence of insufficient EDTA concentrations in plating baths.

Effects of Bath Temperature on Electrodeposited Permanent Magnetic Co-Pt-W(P) Films

The effects of bath temperature on electrochemical behavior, alloy composition, crystallographic structure, morphology and the magnetic properties of electrodeposited Co-Pt-W(P) films were investigated. Electrochemical studies show that alloy electrodeposition has been shifted to more positive potentials and the critical time for nucleation decreased as electrolyte temperature increased. As the temperature increased from 40 °C to 80 °C, tungsten content in the deposit increased, while phosphorus content decreased. The films deposited at T = 40 °C exhibited soft magnetic properties. However, electrodeposited at T = 70 °C, the films exhibited hard magnetic properties. It is also demonstrated that higher temperature more than 70 °C could weaken hard magnetic properties. XRD results indicated that the deposits obtained at 50 °C-70 °C showed enhancement of [00.1] P.O. (preferred orientation) with the bath temperature, which resulted in the stronger perpendicular magnetic anisotropy.

Electropolishing of 304 stainless steel: Surface roughness control using experimental design strategies and a summarized electropolishing model

The electropolishing (EP) settings for obtaining 304 stainless steel (304SS) with variable surface roughness factors (Ra) in a mixture containing phosphoric acid, sulfuric acid, and glycerol were achieved using experimental design strategies, including the fractional factorial design (FFD) coupled with the response surface methodology (RSM) and the path of the steepest ascent. The bath temperature and polishing time were found to be the strongest factors affecting Ra of 304SS in the FFD study. The glycerol content and polishing current density involved strong interactions with the bath temperature although both factors only showed marginal significant effects. The effects of bath temperature and polishing time on Ra of 304SS were examined in the study of the steepest ascent path for controlling the surface roughness. The results showed that Ra of 304SS is decreased with decreasing the bath temperature and polishing time but increased when the temperature was lower than 20 °C. A summarized model with a new idea on the molecular interactions in the polishing bath is proposed to elucidate the phenomena found in this work. The morphologies and Ra of 304SS electropolished under various conditions were examined by means of the SEM photographs and AFM analyses.

Electrosynthesis and characterization of lead oxide thin films

Lead dioxide (PbO 2) is an important oxide material used extensively as anode material in batteries and fuel cells and its study has now taken new strides beyond the wide field of battery research. In the present study, lead dioxide films were electrodeposited onto precleaned copper substrate from nitrate baths. The film composition, morphology and structure were investigated using Energy Dispersive X-ray Analysis (EDX), scanning electron microscopy and X-ray diffraction techniques. The oxidation and reduction potential regions and the mechanism of lead dioxide film formation are discussed using cyclic voltammetry studies. X-ray diffraction results revealed tetragonal [α-PbO 2 + β-PbO 2] structures of the films which are influenced by bath temperature and solution pH value. EDAX studies show that the films deposited at higher bath temperatures and low solution pH values are rich in lead content and low in oxygen content. The effects of bath temperature and solution pH on the morphological features of lead dioxide films are also described.

Effect of Bath Temperature and Current Density on the Formation of Cathodic Hydroxyapatite.

Effect of Bath Temperature and Current Density on the Formation of Cathodic Hydroxyapatite.

Effects of Growth Process on Structural and Optical Properties of Chemical Bath Deposition Cadimium Sulfide Thin Films

Hexagonal CdS thin films with a strong (002) orientation were successfully prepared by chemical bath deposition (CBD) using the reaction between CdCl2 and CS(NH2)2. A commonly available CBD system was successfully modified using a wetting agent (polyglycol) without agitation. Studies were performed to determine the effects of bath temperature on the properties of the films, such as optical transmission, surface morphology and the structure property. It was found that bath temperature plays a vital role in the quality of the CdS films. The increase in bath temperature improved the surface morphology of the CdS films and also decreased the number of pinholes on the films. The optimum bath temperature was 85 °C.

Effect of Bath Temperature on the Electrodeposition Mechanism of Zinc Oxide Film from Zinc Nitrate Solution

film was prepared from zinc nitrate aqueous solution by the potentiostatic technique using a three-electrode system at . The film was characterized by scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. In addition, measurements of interface pH and electrochemical quartz crystal microbalance (EQCM) during the electrodeposition were carried out to elucidate the deposition mechanism. It was disclosed that the deposition scheme at the initial stage is quite different depending on bath temperature. The change in deposition mechanism with temperature is closely related to the increased thermodynamic stability of at high temperature. Based on EQCM analysis, it was suggested that the precursor of is slowly transformed to at low temperature, but the formation of is extremely rapid at high temperature, i.e., directly deposits at high temperature. Auger analysis indicated that transition from the precursor to crystal started from the bottom to the surface when the amount of precursor became larger than a critical value depending on temperature.

Copper Immersion Deposition on Magnesium Alloy: The Effect of Fluoride and Temperature

A study was carried out to examine copper immersion deposition on AZ91 magnesium alloy in a hydrofluoric acid-containing bath. The role of fluoride and the effect of bath temperature were investigated. The study was performed by measuring the ac impedance and open-circuit potentials in combination with X-ray photoelectron spectroscopy and scanning electron microscopy surface analysis. Results showed that the effect of both HF concentration and temperature on copper immersion deposition is significant, via affecting the surface film formation on the magnesium surface. A model for understanding the copper immersion deposition process is depicted based on surface characterization and the electrochemical measurements.

Relation between inelastic electron tunneling and vibrational excitation of single adsorbates on metal surfaces

We analyse theoretically a relation between the vibrational generation rate of a single adsorbate by tunneling electrons and the inelastic tunneling (IET) current in scanning tunneling microscope, and the influence of the vibrational excitations on the rate of adsorbate motions. Special attention is paid to the effects of finite lifetime of the vibrational excitations. We show that in the vicinity and below the IET threshold the rate of adsorbate motion deviates from a simple power-law dependence on the bias voltage due to the effects of bath temperature and adsorbate vibrational lifetime broadenings. The temperature broadening appears to be confined near the threshold voltage within a narrow region of several $k_B T$, whereas the lifetime broadening manifests itself in a much wider region of applied voltages below the IET threshold.

Effect of bath temperature on the electrodeposition of copper tin selenide films from aqueous solution

The effect of bath temperature on Cu 2SnSe 4 films prepared by electrodeposition was studied in this work. The structure, morphology and composition of the films were analysed by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive analysis of X-rays (EDAX). The band gap energy and type of optical transition were determined from optical absorbance data. The results showed that electrodeposition of Cu 2SnSe 4 films was most suitable to be obtained at room temperature. Increasing the bath temperature did not improve the crystallinity of Cu 2SnSe 4 compound, but to formation of binary phase, CuSe. EDAX studies showed that increasing the temperature resulted in drastic increase in Cu content and decrease in Sn content. The optical absorption studies showed the film deposited at room temperature has direct transition with band gap energy E g of 1.2 eV.

Microstructure, Morphology and Corrosion Resistance of Electrodeposited Zinc-Cobalt Compositionally Modulated Alloy Multilayer Coatings

SUMMARYThe morphologies and corrosion resistance of electrodeposited zinc-cobalt compositionally modulated alloy multilayer coatings produced from a sulphate bath have been investigated and reported in this paper. Various current density waveforms were designed using a computer-aided pulse plater unit to deposit zinc-cobalt alloy layers of alternate compositions from 10% cobalt to 70% cobalt. Different numbers of layers with different thicknesses were deposited by designing a variety of current density waveforms. It was shown that designing waveforms with steps to produce a gradual increase or decrease in current densities can prevent crack formation and improves the quality of Zn/Co CMAM coatings. Neutral salt spray corrosion tests showed that Zn/Co CMAM coatings have better corrosion resistance than single layer Zn-Co alloy coatings. Effects of bath temperature and agitation on the corrosion resistance of these CMAM coatings were also investigated. It was found that the best corrosion protection could be achieved for a two layered Co/Zn CMAM coating deposited at 25–30 °C from a bath with a high rate of agitation.

Effect of bath temperature on electrochemical properties of the anodically deposited manganese dioxide

The effect of bath temperature on the electrochemical properties of electrolytic manganese dioxide (EMD) was studied. EMD was produced by anodic deposition from acidic aqueous solution of manganese sulfate at different bath temperatures in the range of 60–120°C. At temperatures above the boiling point of water, the electrolysis was carried out in an autoclave. The EMD produced at 120°C was of gamma type, identified by X-ray diffraction (XRD). Furthermore, the materials produced at 115 and 120°C were quality-controlled by cycling a sample as cathode mix in small size RAM-cells and by scanning electron microscopy. The results indicated an increase in cyclic charge/discharge performance and an improvement of crystallization conditions of EMD produced at elevated temperature when compared to data of commercially available γ-MnO 2.

Study on growth factors of intermetallic layer within hot-dipped 25% Al-Zn alloy coating on steel

25% A1-Zn alloy coating performs better than hot dip galvanized coating and 55% A1-Zn-Si coating with regard to general seawater corrosion protection. This study deals with the interfacial intermetallic layer’s growth, which affects considerably the corrosion resistance and mechanical properties of 25%A1-Zn alloy coatings, by means of three-factor quadratic regressive orthogonal experiments. The regression equation shows that the intermetallic layer thickness decreases rapidly with increasing content of Si added to the Zn-Al alloy bath, increases with rise in bath temperature and prolonging dip time. The most effective factor that determined the thickness of intermetallic layer was the amount of Si added to Zn-Al alloy bath, while the effect of bath temperature and dip time on the thickness of intermetallic layer were not very obvious.

Galvanostatic electrodeposition and microstructure of copper (I) oxide film

Polycrystalline copper (I) oxide films were deposited on stainless steel substrate by galvanostatic electrodeposition method and were characterized by X-ray diffraction and scanning electron microscopy. The effect of bath temperature, bath pH and current density on the compositon, grain size, surface texture and surface morphology of the electrodeposited films were investigated. The films deposited at low bath pH (≤7) consisted of copper (I) oxide and metallic copper; while the films deposited at bath pH between 8 and 12 and bath temperature of 60°C were pure copper (I) oxide. The preferred orientation of the copper (I) oxide films depended on the relative growth rate of {111} and {200} faces and could be controlled by adjusting the bath pH and/or the cathodic current density. (100)-oriented copper (I) oxide films could be deposited at pH=9 and current densities in the range of 0.25–1 mA/cm2, while (111)-oriented films could be prepared at pH=12 or at pH=9 using the current densities between 1.5–2.5 mA/cm2. Computer simulated crystallite shapes showed that the crystal shape changed from octahedral for (100)-oriented film to trucated pyramids and cubs for (111)- oriented film. And they were approved by scanning electron microscopy.

ZnO/CdS/CuInSe 2 photovoltaic cells fabricated using chemical bath deposited CdS buffer layer

CdS thin films have been prepared by using chemical bath deposition. The effects of bath temperature and concentration of NH 4OH were studied. Optimum deposition conditions were established. The resulted CdS thin films exhibit optical transmissions in excess of 90% over the majority of the solar spectrum. ZnO/CdS/CuInSe 2 solar cells were fabricated on electrodeposited CuInSe 2 thin films. A conversion efficiency of 6.3% was obtained with an active area of 7.8 mm 2 (no AR coating).

ヘキサヒドロオクソ白金酸塩を用いたアルカリ性白金電鋳浴

We studied the influence of bath composition, operating conditions, and impurities on a platinum electroforming bath using hexahydroxoplatinate salt.The effect of bath temperature on deposite were studied using a platinum concentration of 13g/L and a pH of 135.Crack-free deposits resulted at temperatures of exceeding 85°C. At a platinum concentration of 26g/L, the pH was 13.5 and temperature 90°C, yielding a 60μm platinum foil. The platinum content of deposits exceeded 99.9%, which contained palladium, rhodium, gold, silver, copper, and iron impurities.X-ray diffraction imaging showed a strong (200) orientation on ductile deposits.Deposit hardness exceeded 300Hv and hardness decreased in heat treatment exceeding 600°C.The bath thus is easily influenced by impurities.Calcium is thought to be a deterioration agent.The presence of calcium, strontium or barium made the deposit less ductile and brighter.The influence of alkaline earth metals was eliminated through electrolysis, coprecipitation with magnesium hydroxide, and absorption to chelate resin.

Effect of SC-1 Process Parameters on Particle Removal and Surface Metallic Contamination

ABSTRACTThe effect of bath temperature, megasonic power, and NH4-OH:H2O ratio are studied for particle removal efficiency, surface roughness, and surface Fe concentration in SC-1 cleaning solutions. Experimental results are presented which show removal efficiencies better than 97% on bare silicon wafers for optimized process conditions. These results are related to the etch rate of thermal oxides and a model is developed for reducing surface roughness and minimizing Fe contamination levels while maximizing particle removal efficiency.