Properties of nickel-cobalt-diamond composite coating deposited from a chloride electrolyte

Effect of electrolysis modes and electrolyte composition on physicomechanical properties of nickel-cobalt-diamond composite electroplated coatings deposited from a chloride electrolyte with introduction of an ultradispersed diamond suspension was studied and the possibility of replacement of wear-resistant chromium coatings with these composite coatings was demonstrated.     

Dependence of physicomechanical properties of a nickel-cobalt-aluminum oxide composite electrolytic coating on the dispersity of the alloying component

Effect of the dispersity of aluminum oxide on the microhardness, wear, internal stresses, and porosity of nickel-cobalt-aluminum oxide composite electrolytic coatings deposited from a chloride electrolyte and the dependence of the content of aluminum oxide in the coating on the agitation rate and working duration of the electrolyte were studied.     

Wear resistance of electrolytic nickel-boron alloy deposited from a chloride electrolyte

Dependence of the wear resistance of an electrolytic nickel-boron alloy deposited from a chloride electrolyte on the alloy composition, thermal treatment temperature, and specific load on friction surfaces was studied.     

Study of properties of lustrous nickel coatings deposited from a low-concentration chloride electrolyte

Effect of electrolysis modes on the physicomechanical properties of lustrous nickel coatings deposited from a low-concentration chloride electrolyte was examined. Results obtained in an experimental study of the industrial use of the given electrolyte are presented.     

Physicomechanical properties of nickel coating deposited from sulfate nickel plating electrolyte using preliminary underpotential deposition

A study of nickel coatings electroplated from electrolytes of the compositions (M) NiSO₄ 0.5, NiCl₂ 0.3, and H₃BO₃ 0.404 (electrolyte 1) and NiSO₄ 0.5, NiCl₂ 0.3, and H₃BO₃ 0.404 with the addition of 2 mg L^–1 RADO (electrolyte 2) in the constant-current mode after preliminary potentiostatic treatment (underpotential deposition) of the support revealed the formation of Fe–Ni alloy in the initial moment of formation of the nickel coating. Pretreatment of the steel surface in the underpotential deposition mode allows preparation of uniform finely crystalline nickel coatings with enhanced levels of the wear resistance, microhardness, and corrosion resistance.     

Properties of a nickel-boron-fluoroplastic electrolytic composite coating

Dependence of the wear and corrosion resistance of a nickel-boron-fluoroplastic electrolytic composite coating deposited from a chloride electrolyte on the electrolyte composition and electrolysis conditions and modes was studied.     

Cobalt titanate–cobalt oxide composite thin films deposited from heterobimetallic precursor

A single molecular heterobimetallic complex, [Co₂Ti(μ₃‐O)(TFA)₆(THF)₃] (1) [TFA = trifluoroacetate, THF = tetrahydrofuran], was synthesized, structurally and spectroscopically characterized and implemented as a single‐source precursor for the preparation of CoTiO₃–CoO composite thin films by aerosol‐assisted chemical vapour deposition (AACVD). The precursor complex was prepared by interaction of Co(OAc)₂.4H₂O [OAc = (CH₃COO^?)] with Ti(iso‐propoxide)₄ in the presence of trifluoroacetic acid in THF, and was analysed by melting point, CHN, FT‐IR, single‐crystal X‐ray diffraction and thermogravimetric analysis. The precursor complex thermally decomposed at 480 °C to give a residual mass corresponding to a CoTiO₃–CoO composite material. Good‐quality crystalline CoTiO₃–CoO composite thin films deposited at 500 °C by AACVD and characterized through powder X‐ray diffraction and scanning electron microscopy/energy‐dispersive X‐ray spectroscopy show that the crystallites have a rose‐flower‐like morphology with an average petal size in the range of 2–6 µm. Copyright © 2012 John Wiley & Sons, Ltd.     

Ni-W alloy coatings deposited from a citrate electrolyte

Ni-W alloy coatings were deposited by applying current pulses with different pulse parameters at 60°C onto mild steel substrates from aqueous electrolytes with different tungstate concentration. Morphology and composition of the alloys were analyzed by SEM and EDX, respectively. XRD was used to determine metallic phases. Scanning electron micrographs revealed that deposition parameters had a strong effect on the morphology of the coatings. Increasing the duty cycle or decreasing the off time led to a compact morphology. Corrosion properties of the coatings were investigated by potentiodynamic polarization in a chloride medium. It was found that compact morphology of the deposits and high content of tungsten in the coating contribute to satisfactory corrosion results of Ni-W alloy coatings under the conditions studied.     

Solid-state electrochemical lithium cells with oxide electrodes and composite solid electrolyte

The LiClO₄-Al₂O₃ composite solid electrolyte and solid solutions LiFe _x Mn_2?x O₄ and Li₅Ti₄O₁₂ compositions are synthesized and their physicochemical properties are studied using the x-ray diffraction and electrical measurements. Based on composition 0.5LiClO₄-0.5Al₂O₃, whose conductivity is the highest, first experiments on the elaboration of model electrochemical solid-electrolyte lithium cells with LiMn₂O₄, LiFeMnO₄, LiFe_0.8Mn_0.2O₄, and Li₅Ti₄O₁₂ oxide spinel electrodes are performed.     

Properties of composite solid polymer electrolyte using hyperbranched polymer with ether-linkage

The cross-linked composite solid polymer electrolytes composed of poly(ethylene oxide), lithium salt (LiN(SO₂CF₃)₂), and a hyperbranched polymer whose repeating units were connected by ether-linkage (hyperbranched polymer (HBP)-2) were prepared, and their ionic conductivity, thermal properties, electrochemical stability, mechanical property, and chemical stability were investigated in comparison with the non-cross-linked or cross-linked composite solid polymer electrolytes using hyperbranched polymers whose repeating units were connected by ester-linkage (HBP-1a, 1b). The cross-linked composite solid polymer electrolyte using HBP-2 exhibited higher ionic conductivity than the non-cross-linked and cross-linked composite solid polymer electrolytes using HBP-1a and HBP-1b, respectively. The structure of the hyperbranched polymer did not have a significant effect on the thermal properties and electrochemical stability of the composite solid polymer electrolytes. The tensile strength of the cross-linked composite solid polymer electrolyte using HBP-2 was lower than that of the cross-linked composite solid polymer electrolyte using HBP-1b, but higher than that of the non-cross-linked composite solid polymer electrolyte using HBP-1a. The HBP-2 with ether-linkage showed higher chemical stability against alkaline hydrolysis compared with HBP-1a with ester-linkage.     

Electrodeposition of nickel-based composite coatings from a sulfamate electrolyte

Russian Journal of Applied Chemistry - Nickel-based composite coatings modified with carbon nanotubes were electrodeposited from a sulfamate electrolyte. The functional properties (friction...     

Emission of active oxygen forms from a deposited bismuth oxide

The specific features of the emission of singlet oxygen from deposited bismuth oxide were examined. It was established how the rate of the emission of singlet oxygen depends on the concentration of deposited bismuth oxide. The largest amount of singlet oxygen was emitted from the sample with a crystalline structure. It was shown that only singlet molecular oxygen is emitted from deposited bismuth oxide.     

Electrodeposition of iron/titania composite coatings from methanesulfonate electrolyte

The possibility of deposition of Fe/TiO₂ composite electroplated coatings from methanesulfonate electrolyte was demonstrated. The kinetics of the codeposition of dispersed phase particles is described by the Guglielmi model. Incorporation of titania particles into the iron matrix leads to enhancement of the coating microhardness due to dispersion strengthening. The Fe/TiO₂ composite coatings exhibit catalytic activity in photochemical decomposition of Methyl Orange dye in aqueous solution.     

Analysis of a polytetrafluoroethylene coating deposited onto polyester fibers from supercritical carbon dioxide

A low-molecular-weight polytetrafluoroethylene coating deposited onto a polyester textile material from supercritical carbon dioxide with the aim to make the material hydrophobic was analyzed. The hydrophobic properties of the coating were examined in comparison with those of the hydrophobizing agent produced by Nuva (Switzerland).     

Electrodeposition of hard iron-zirconia dioxide composite coatings from a methanesulfonate electrolyte

A study of electrodeposition of iron-based composite coatings containing zirconia dioxide particles from sulfate and methanesulfonate electrolytes showed that the zirconia dioxide content in the deposits obtained from the latter electrolyte can reach 10–12 wt %. Models of the process of ZrO₂ particle incorporation into an iron matrix were considered. The microhardness of the composite deposits was estimated.     

Possibility of raising the deposition rate of nickel coatings from a chloride electrolyte

Conditions under which nickel coatings can be deposited from a chloride electrolyte at a high rate were studied. The mechanism of this process was suggested and experimentally confirmed. The mass-transfer rate of nickel-containing particles was determined by chronopotentiometry, with temperature raised from 20 to 50°C. The dependence of pH_s on the current density was determined. Physicochemical parameters of the coatings (microhardness, internal stresses, porosity, luster, and adhesion) were measured.     

Ion-chromatographic determination of chloride and fluoride in electrolyte from the halogen tin-plating process

A simple and rapid procedure is proposed for the determination of chloride and free fluoride in tin electroplating fluid. Suppressor-column ion-chromatography is used after oxidation of hexafluorostannate(II) to hexafluorostannate(IV) with hydrogen peroxide. Concurrent determination of tin(II) and total tin then allows calculation of the concentrations of fluoride, hexafluorostannate(II) and hexafluorostannate(IV).     

Properties of mixed aqueous solutions of methyl cellulose with polyethylene oxide and of composite films prepared from them

Rheological properties of mixed dilute and moderately concentrated aqueous solutions of methyl cellulose with polyethylene oxide were studied. Composite films were prepared from these solutions, and their physicomechanical properties and structural organization were examined.     

Layered molybdenum oxide thin films electrodeposited from sodium citrate electrolyte solution

Molybdenum oxide thin films were prepared electrochemically onto the selenium predeposited tin oxide-coated glass substrates using 0.22 M sodium citrate (C₆H₅Na₃O₇) solution (pH 8.3) and sodium molybdate as a precursor. Cyclic voltammetry was used to determine the deposition potential effects on molybdenum compound speciation, while quantitative thin film composition was obtained from X-ray photoelectron spectroscopy depth profiles. Thin molybdenum film growth and composition was potential dependant. Predominant molybdenum species was Mo(IV) at all deposition potentials and deposition times. Optical properties of the molybdenum oxide thin films were determined using UV–VIS spectroscopy. The absorption edge varied between 560 and 650 nm, whereas optical band gap values—between 1.79 and 2.19 eV—well within the limits for solar light-induced chemical reactions.     

Melt crystallization and segmental dynamics of poly(ethylene oxide) confined in a solid electrolyte composite

The isothermal melt crystallization and the corresponding segmental dynamics, of a high molecular weight poly(ethylene oxide) (PEO) confined by Li₇La₃Zr₂O₁₂ (LLZO) particles in solid electrolyte composites, were monitored by differential scanning calorimetry (DSC) and dielectric relaxation spectroscopy (DRS), respectively. Our results show that the overall crystallinity is positively correlated with the surface area of LLZO particles. The primary and secondary crystallization processes are identified by a modified Avrami equation, while two dynamic modes, the α relaxation and α′ relaxation, were in the DRS measurements. The results reveal an unambiguous correlation between the primary crystallization and the α relaxation, while a correlation between the second crystallization and the α′ relaxation concurrently exist in the electrolyte composites. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 466–477