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Nanocrystalline Ni-Mo alloy coatings with excellent brightness, high hardness, and corrosion resistance were prepared. Nanocrystalline Ni-Mo alloy coating with a Mo content of 14.94 at% was electrodeposited on the copper foil substrate under the optimized conditions with the current efficiency of 51.64%. The electrodeposition behavior of Ni-Mo alloy coatings was studied by cathodic polarization curve and chronopotentiometry. Chronopotentiometry showed that the nucleation rate of Ni-Mo alloys can be accelerated with the increase of current density. Meanwhile, the cathodic polarization curves show that the additives can effectively inhibit the electrodeposition of Ni-Mo alloys. The (2 0 0) and (2 2 0) diffraction peaks of Ni gradually disappeared and the grain size gradually decreased with the increase of Mo content in the alloy coating according to XRD and TEM analysis. Scanning electron microscope (SEM) and confocal microscope observation results show that the coating becomes smoother and denser with the increase of Mo content when Mo content was lower than 14.94 at%, after which the density of the coating saw a decline due to the intensified hydrogen evolution reaction. The microhardness results of the alloy coating show that the microhardness of the alloy coating is related to the solid solution strengthening, texture evolution, and plastic deformation of the alloy. Meanwhile, the alloy coating has a Hall-Petch relationship and inverse Hall-Petch relationship, and the critical grain size is 5.5 nm. The corrosion resistance of Ni-Mo alloy coating is better than that of pure Ni coating, and the corrosion resistance is optimal when the Mo content is about 15 at%. In addition, in the plating solution containing additives, the deposited Ni-Mo alloy coating is smoother and denser, and the hardness and corrosion resistance of the alloy coating is also greatly improved. [Display omitted] • The minimum grain size of nanocrystalline Ni-Mo alloy coatings can reach 2.7 nm. • The hardness and corrosion resistance of nanocrystalline Ni-Mo alloy coatings are higher than pure Ni coatings. • Composite additives can significantly increase Ni-Mo alloy polarization. [ABSTRACT FROM AUTHOR]

Abstract: Electrodeposition of Cu–Li alloy from 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][BF4]) ionic liquid was investigated. The cyclic voltammetry behaviors of [BMIm][BF4] containing Cu(II), Li(I), and mixtures of Cu(II) and Li(I) were studied at a copper working electrode, separately. The Cu–Li alloy produced by direct current electrodeposition was characterized by inductively coupled plasma atomic emission spectrometry (ICP), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The function of 2-butyne-1,4-diol was studied by linear sweep voltammetry. The result shows that the 2-butyne-1,4-diol could improve Li content in deposit, and make the Cu–Li alloy deposits denser and finer. [Copyright &y& Elsevier]

Abstract: Porous anodic alumina template is synthesized by electrochemical anodization of aluminum and used to grow cobalt nanowires. The cobalt nanowires produced by direct current electrodeposition are characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction and physical property measurement system. Test results indicate that the average diameter of cobalt nanowires is about 45nm, which is generally the same as the pore diameter of porous anodic alumina template, and the cobalt nanowires electrodeposited from mixture of 1-ethyl-3-methylimidazolium chloride ionic liquid and ethylene glycol have a smoother surface and better magnetic properties than cobalt nanowires electrodeposited from aqueous solution, and they show a better squareness. Therefore it can be concluded that the cobalt nanowires electrodeposited from mixture of 1-ethyl-3-methylimidazolium chloride ionic liquid and ethylene glycol using porous anodic alumina template can be used as a perpendicular magnetic recording film. [Copyright &y& Elsevier]

BMIm-OTF (1-Butyl-3-methylimidazolium trifluoromethanesulfonate) ionic liquid and alcohols/different volume fraction of n -propyl alcohol (normal propyl alcohol) mixed electrolytes are studied for the first time. The electrochemical behaviors of CIGS are investigated by cyclic voltammetry (CV) in ionic liquid and alcohols mixed electrolytes, respectively. The morphological properties of CIGS films are detected using scanning electron microscopy (SEM). Raman spectra at around 175 cm − 1 are normalized to the dominant A 1 mode. The structural properties and various phases are determined by using X-ray diffraction (XRD) and Raman techniques. The XRD results indicate that the CIGS phase formed by incorporating Ga into the CIS phase. The Cu 1.00 In 0.45 Ga 0.1 Se 2.26 thin films present as a p-type semiconductor and the Ga/(Ga + In) = 0.18 which electrodeposited from BMIm-OTF/ n -propyl alcohol (30 vol%) mixed electrolytes. The band gap of the obtained CIGS thin film is approximately 1.48 eV, as measured using UV–visible absorption spectra. The carrier concentration and average Hall coefficient of the CIGS thin films are 6.366 × 10 19 cm − 3 and 9.806 × 10 − 2 cm 3 /C, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The electrodeposition of metallic cobalt from a 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid was investigated. The electrochemical behavior of Co(II) in the ionic liquid on a platinum working electrode at 60°C was studied by cyclic voltammetry and chronoamperometry. The results from the cyclic voltammetry showed that the electrodeposition of metallic Co in the ionic liquid was an irreversible process and controlled by the diffusion of Co(II) on a platinum working electrode. The average value of αn α was calculated to be 0.35 and the diffusion coefficient (D 0) of Co(II) was calculated to be 1.76×10−8 cm2/s at 60°C. Chronoamperometric results indicated that the electrodeposition of Co on a platinum working electrode followed the mechanism of instantaneous nucleation and three-dimensional growth with diffusion-controlled. The cobalt plating was uniform, dense, shining in appearance with good adhesion to the platinum substrate at 60°C. The scanning electron microscope (SEM) micrographs were used to confirm that the cobalt plating was denser and finer at 60°C. Energy dispersive X-ray analysis (EDAX) profile showed that the obtained plating was pure cobalt. X-ray diffraction (XRD) pattern indicated that there was a preferred orientation direction and the average size of cobalt grains was 40nm. [Copyright &y& Elsevier]

In order to replace the highly poisonous cyanide zincate process of Al alloy, an eco-friendly approach was developed, i.e., electrodeposition of Cu-Zn coating from ionic liquid/ethanol mixed bath. It was demonstrated that the Cu 5 Zn 8 alloy produced from 1-ethyl-3-methylimidazolium trifluoromethylsulfonate (EMImTfO) and 20% (Volume percent) ethanol mixtures under optimal conditions showed cauliflower-shaped structure with a (330) preferred orientation, which could significantly improve the corrosion resistance of Al substrate in Watts bath, thereby elevating Ni coating quality. The overall property of Cu-Zn intermediate layer and its subsequent coating, including compactness, adhesive strength and corrosion resistance is approximately the same as that of cyanide zincate layer and its surface coating, suggesting that the new method is an ideal alternative to conventional zincate treatment. • Cu-Zn coating is electrodeposited from EMImTfO ionic liquid/ethanol mixtures. • Its overall property is approximately the same as that of cyanide zincate layer. • A high-quality Ni coating can be obtained on Cu-Zn coating from Watts bath. • It also has similar property to the Ni coating deposited on cyanide zincate layer. • This method has the great potential to replace cyanide zincate process of Al alloy. [ABSTRACT FROM AUTHOR]

Three-dimensional ordered macroporous (3DOM) CuIn x Ga 1−x Se 2 (CIGS) film is synthesized by one-step galvanostatic electrodeposition based on polystyrene templates from a special mixture of ionic liquid 1-butyl-3-methylimidazolium tetra-fluoroborate and ethanol. X-ray diffraction pattern, Raman spectroscopy and transmission electron microscopy present the CIGS film has ideal chalcopyrite crystallization. 3DOM CIGS film with high Ga content has photochemical activity and good photo-stability, its band gap is 1.34 eV. This is a simple, feasible and additive free method without selenization process to synthesize 3DOM CIGS film, the film is qualified and available for absorber-layer fabrication or other fields. [ABSTRACT FROM AUTHOR]

Stoichiometric Cu 1.00 In 0.51 Ga 0.1 Se 2.04 (CIGS) thin films containing Cu(II), In(III), Ga(III) and Se(IV) are obtained for the first time in ionic liquid/n-propyl alcohol mixtures with controlled pulse electrodeposition parameters at 323 K. The effects of deposition current density, deposition time, frequency and duty cycle are studied in detail. The band gap of obtained CuIn x Ga 1− x Se 2 (CIGS) thin film are approximately 1.35 eV, as measured using UV–visible absorption spectra. The interplanar spacing and average Hall coefficient of the CIGS thin films are approximately 3.315 Å and 1.011×10 −1 cm 3 /C, respectively. [ABSTRACT FROM AUTHOR]