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Binary and ternary Fe-W and Fe-W-P films have been obtained electrochemically by using an alkaline stable bath of Fe(III) with a new complexing agent (nitrilotriacetic acid trisodium salt monohydrate-NTA), adequate to avoid carbon incorporation in the deposits and assure the bath durability. The different stages to obtain the alloy deposits through induced co-deposition have been proposed. Significant tungsten percentages in the deposits have been obtained, resulting stable amorphous films with soft-magnetic properties. However, it has been necessary to simplify the deposition process to obtain Fe-W alloy nanowires by means of induced co-deposition in the interior of polycarbonate membranes. For first time, Fe-W magnetic nanowires have been synthesised by templated induced co-deposition. [ABSTRACT FROM AUTHOR]

Abstract: ZnNi alloy electrodeposition on a 1010 steel electrode in boric-acid baths containing sorbitol, mannitol or glycerol was investigated by cyclic voltammetry. Electrodeposits obtained galvanostatically were characterized by SEM, EDS and XRD. It was found that in baths containing sorbitol or mannitol, the deposition current density (j d ) was reduced, but in none of the baths was the initial deposition potential affected. SEM images of deposits revealed that the boric-sorbitol and boric-mannitol complexes refine the grain, even at high j d . XRD patterns of the ZnNi deposits produced at j d =50mAcm−2, in ZnNi1 bath and in ZnNi1 bath contained sorbitol or mannitol, indicated that the films were formed mainly of Zn and γ1 phases. To ZnNi2 baths contained glycerol the films were formed of γ and γ1 phases. The Ni content in the deposits produced in the bath without polyalcohol or containing glycerol increased from ~5 to 19wt.% with increasing j d . With sorbitol or mannitol, there was a smaller rise from ~7 to 10wt.% Ni. Thus, ZnNi deposits providing sacrificial protection can be obtained in baths with or without polyalcohol. The linear polarization method showed that ZnNi alloy deposited from baths contained polyalcohol have greate R p . [Copyright &y& Elsevier]

Abstract: This paper shows the study of silver–zinc electrodeposition from a thiourea solution with added (ethylenedinitrilo)tetraacetic acid (EDTA), disodium salt and N-(2-hydroxyethyl)ethylenediaminetriacetic acid (HEDTA), trisodium salt. Voltammetric results indicated that silver–zinc alloy can be obtained applying overpotential higher than 0.495V, in Tu solution containing 1.0×10−1 molL−1 Zn(NO3)2 +2.5×10−2 molL−1 AgNO3. This was due to silver(I) ion complexation with thiourea, which shifted the silver deposition potential to more negative value and due to silver–zinc alloy deposition, which occurred at potentials more positive than the potential to zinc deposition alone. EDTA or HEDTA did not significantly affect the silver and zinc deposition potentials, but decreased the current density for silver–zinc deposition. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analyses of the silver–zinc deposits showed that the morphology and composition changed as a function of the conditions of deposition, viz, deposition potential (E d), deposition charge density (q d) and solution composition (silver, EDTA and HEDTA concentrations). EDS analysis of the deposits showed sulphur (S) incorporated into the silver–zinc deposit, while SEM images showed that this sulphur content seemed to improve the silver–zinc morphology, as did the presence of EDTA and HEDTA in the solution, which enhanced the sulphur incorporation into the silver–zinc deposit. X-ray diffraction (XRD) analysis of the silver–zinc deposit showed that it was amorphous, irrespective of its composition and morphology. [Copyright &y& Elsevier]

The galvanostatic technique was used to analyze the electrodeposition of Cu–Zn on to AISI 1010 steel electrode from an alkaline-sorbitol bath with various proportions of the metal ions in the bath: Cu70/Zn30, Cu50/Zn50 and Cu30/Zn70. Coloration of Cu–Zn films were whitish golden, light golden, golden/gray depending on the Cu 2+ /Zn 2+ ratios in the electrodeposition bath, deposition current density ( j dep ) and charge density ( q dep ). The highest current efficiency was ∼54.0%, at j dep −1.0 mA cm −2 and q dep 0.40 C cm −2 in the Cu70/Zn30 bath. Energy dispersive spectroscopy indicated that electrodeposits produced from the bath Cu70/Zn30 showed higher Cu content at lower j dep . Also, for same j dep the Cu content increased with q dep . Scanning electron microscopy showed that Cu–Zn electrodeposits of high quality were obtained from the Cu70/Zn30 bath, since the films were fine-grained, except the obtained at j dep −20.0 mA cm −2 and q dep 10.0 C cm −2 . Also, these electrodeposits did not present cracks. X-ray analysis of the Cu–Zn electrodeposits obtained at j dep −8.0, −20.0 and −40.0 mA cm −2 , in each case, with q dep 2.0 and 10.0 C cm −2 , in the Cu70/Zn30 bath, suggested the occurrence of a mixture of the following phases, CuZn, CuZn 5 and Cu 5 Zn 8 . Galvanostatic electrodeposits of Cu–Zn obtained from sorbitol-alkaline baths exhibited whitish golden color, with good prospects for industrial applications, especially for decorative purposes. [ABSTRACT FROM AUTHOR]