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Antimony nanowires have been synthesized by template-free electrodeposition at room temperature from the ionic liquid (IL) 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([Py1,4]TFSI) containing 0.5 mol/L SbCl3. The nanowires are shown to have a diameter of ~ 50 nm and a length of ~ 10 µm. Sb nanowires can only be obtained by a two-step electrochemical process, requiring first a cyclic voltammetry step followed by the electrodeposition step. In situ XPS is employed to investigate the speciation formed during the electrochemical reduction process. The results reveal that the XPS core level peaks of the IL and of SbCl3 components shift their binding energies towards higher values accordingly with the applied negative cell voltage. Additional peaks at lower binding energies than those of Sb3+/IL at the OCP can be attributed to the adsorption of reduced Sb species. The formed species together with the IL solvation layers play an important role in the formation of Sb nanowires. [ABSTRACT FROM AUTHOR]

In this paper, the influence of various concentrations of water on the electrochemical and spectroscopic behavior of 1-ethyl-3-methylimidazolium acetate ([EMIm]OAc) and of 1 M Zn(OAc)2/[EMIm]OAc has been investigated. The results show that the added water can reduce the viscosity and improve the conductivity of the employed electrolyte. Spectroscopy results reveal that both [EMIm]OAc and 1 M Zn(OAc)2/[EMIm]OAc interact with water and the extent of interaction varies with the amount of water. Furthermore, the electrochemical behavior of 1 M Zn(OAc)2/[EMIm]OAc is changed with the addition of different concentrations of water. A minimum of 20 vol% water was necessary to electrodeposit Zn from 1 M Zn(OAc)2/[EMIm]OAc at room temperature. Moreover, 1 M Zn(OAc)2/[EMIm]OAc with 20 vol% water was assessed for its possible application as an electrolyte in a Zn-air battery. [ABSTRACT FROM AUTHOR]

Obtaining titanium (Ti) coatings on industrially relevant materials at room temperature would be beneficial due to its excellent corrosion resistance and strength. Ionic liquids (ILs) have been discussed as electrolytes for this purpose, but, efforts to electrodeposit titanium from its halide sources in ILs failed due to titanium subhalide formation. Herein,we have investigated the electrode/electrolyte interface (EEI) of TiCl4 in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide, [Py1,4]TFSA, with a focus on the changes in the nanostructure at varying concentrations of the Ti precursor using Atomic Force Microscopy (AFM). Furthermore, the solution species of varying TiCl4 concentrations were investigated by Raman Spectroscopy. The AFM results reveal that the concentration of TiCl4 influences strongly the interfacial nanostructure of the Au(111)/electrolyte interface. A typical 'IL' multilayered structure can be seen upon adding 0.1 M TiCl4 to the IL, which disrupts completely upon further increasing the concentration to ≥ 0.25 M. Furthermore, the AFM force-distance profiles showed that quite soft films have been formed on the electrode surface under electrolysis conditions, which could influence the reduction processes to obtain elemental Ti. Our results reveal that the concentration of TiCl4 can influence strongly the EEI nanostructure and can provide some new fundamental insights into the double layer structure of TiCl4 in [Py1,4]TFSA. [ABSTRACT FROM AUTHOR]

Electrostatic interactions are characteristic of ionic liquids (ILs) and play a pivotal role in determining the formation of species when solutes are dissolved in them. The formation of new species/complexes has been investigated for certain ILs. However, such investigations have not yet focused on eutectic liquids, which are a promising class of ILs. These liquids (or liquid coordination complexes, LCCs) are rather new and are composed of cationic and anionic chloro complexes of metals. To date, these liquids have been employed as electrolytes to deposit metals and as solvents for catalysis. The present study deals with a liquid that is prepared by mixing a 1.2:1 mol ratio of AlCl3 and 1-butylpyrrolidine. An attempt has been made to understand the interactions of FeCl2 with the organic molecule using spectroscopy. It was found that dissolved Fe(II) species interact mainly with the IL anion and such interactions can lead to changes in the cation of the electrolyte. Furthermore, the viability of depositing thick magnetic films of Fe and Fe-Al has been explored. [ABSTRACT FROM AUTHOR]

In the present paper, we report on the electrodeposition of aluminium, zinc and platinum on silver-coated textile fibres from ionic liquids. For electrodeposition of Al, the 60:40 mol% mixture of AlCl/1-ethyl-3-methylimidazolium chloride ([EMIm]Cl) and 1.7 M AlCl in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide ([Py]TFSA) were employed. It was observed that microcrystalline aluminium was electrodeposited on the textile fibres in 60:40 mol% AlCl/[EMIm]Cl. The deposited Al layers either on single fibres or on textile assemblies are well adherent and uniform. An adherent, homogeneous and nanocrystalline Al layer was obtained on the silver-coated textile samples from 1.7 M AlCl/[Py]TFSA at 75 °C. The obtained Al layers from 60:40 mol% AlCl/[EMIm]Cl on the textile fibres exhibit a good corrosion resistance in an aqueous iodide/iodine electrolyte. Furthermore, we obtain Al microtubes from the investigated ionic liquids after dissolving the textile fibres. In addition, zinc electrodeposition was carried out on the textile samples from 60:40 mol% ZnCl/[EMIm]Cl at 80 °C. The electrodeposition of platinum on the textiles was done from 50 mM PtCl in 1-butyl-1-methylpyrrolidinium dicyanamide ([Py]DCA). [ABSTRACT FROM AUTHOR]

Metallic zinc is a promising anode material for rechargeable Zn-based batteries. However, the dendritic growth of zinc has prevented practical applications. Herein it is demonstrated that dendrite-free zinc deposits with a nanocrystalline structure can be obtained by using nickel triflate as an additive in a zinc triflate containing ionic liquid. The formation of a thin layer of Zn-Ni alloy (η- and γ-phases) on the surface and in the initial stages of deposition along with the formation of an interfacial layer on the electrode strongly affect the nucleation and growth of zinc. A well-defined and uniform nanocrystalline zinc deposit with particle sizes of about 25 nm was obtained in the presence of NiII. Further, it is shown that the nanocrystalline Zn exhibits a high cycling stability even after 50 deposition/stripping cycles. This strategy of introducing an inorganic metal salt in ionic liquid electrolytes can be considered as an efficient way to obtain dendrite-free zinc. [ABSTRACT FROM AUTHOR]

In this paper, we present a simple and viable route for the synthesis of germanium-tin alloys (GeSn) from two different ionic liquids, namely, 1-butyl-1-methylpyrrolidinium trifluoromethylsulfonate ([Py]TfO) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide ([Py]TfN). Cyclic voltammetric analysis showed that in the presence of both SnCl and GeCl precursors, a shoulder peak is obtained which is related to the formation of GeSn. Constant potential deposition was performed to obtain GeSn thin films. Furthermore, on changing the concentration of GeCl and SnCl in [Py]TfO, the GeSn composition could be varied. [ABSTRACT FROM AUTHOR]

The electrodeposition of Zn on Au(111) was investigated with cyclic voltammetry (CV) and in situ scanning tunneling microscopy (STM) in the air and water stable ionic liquid 1-ethyl-3-methylimidazolium trifluoromethylsulfonate ([EMIm]TfO) with a Zn(TfO) concentration of 0.2 M. It has been found that the structure [EMIm]TfO/Au(111) is very complex. Furthermore, the addition of Zn(TfO) changes the interfacial structure significantly. The first STM-probed Zn islands appear at +0.3 V, and their growth leads to the formation of a thin zinc layer. A bulk deposition of Zn is obtained with in situ STM at −0.1 V. Furthermore, in situ STM reveals that the deposition of Zn is accompanied by the formation of Au-Zn surface alloys. [ABSTRACT FROM AUTHOR]

Ionic liquids can be applied to recover tantalum capacitors from scrap printed circuit boards. Dissolution experiments with epoxy covered through-hole tantalum capacitors in Lewis acidic mixtures of dialkylimidazolium halides and aluminum trichloride show that all parts, except the tantalum anode, are dissolved in the ionic liquid. This comprises MnO2 from the capacitor's electrolyte as well as tin and silver from the metallic contacts. The latter ones can be directly recovered from the solution by electrodeposition. The tantalum anode is mechanically separated and suitable for further metallurgical processing. [ABSTRACT FROM AUTHOR]

Three dimensionally ordered macroporous (3DOM) Ge/Al and Ge/Si bilayer films have been made via ordered polystyrene (PS) templates by electrodeposition from ionic liquids (IL), at room temperature. For this purpose, the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMIm]Tf2N) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide ([Py1,4]Tf2N) with aluminium, germanium and silicon chlorides dissolved in were used as electrolytes. Self-assembled PS colloidal crystals were made by the vertical deposition method and used as templates. Germanium was chosen as the first layer, then after washing and drying Al and Si layers were deposited subsequently. SEM results verify that the 3DOM Ge/Al and Ge/Si have a different morphology, and EDX was used to analyze the composition of the samples. Novel 3DOM bilayer films made from reactive elements could have some potential as anode host material in future generation lithium ion batteries and can be regarded as the first step to make 3D ordered macroporous bilayer films. [ABSTRACT FROM AUTHOR]

Abstract: This study shows for the first time that poly(p-phenylene) (PPP) nanowires can be easily obtained by electrochemical synthesis at room temperature. The method involves the template assisted electropolymerization of benzene in the air and water stable ionic liquid 1-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate ([HMIm]FAP). Track-etched polycarbonate membranes (PC) with an average pore diameter of 90nm were used as templates. Dense and highly flexible bundles of PPP nanowires with a high aspect ratio (>160) were easily obtained by this method. In addition, we present here our first results to obtain PPP/TiO2 nanowires by the combination of a sol–gel technique with electropolymerization. HR-SEM, TEM and EDX were used for the structural characterization of the nanowires. [Copyright &y& Elsevier]

The fascinating properties of ionic liquids make it possible to synthesize semiconductor nanostructures via a simple and low-cost electrochemical pathway. The present paper summarizes our recent work on the synthesis of Si, Ge, and SixGe1-x nanostructures from ionic liquids: thin films, nanowires and photonic crystals. We also introduce our first results on the template-assisted electrodeposition of SixGe1-x photonic crystals from 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMIm]Tf2N) ionic liquid, and some optical measurements on the previously prepared Ge photonic crystals. Our results confirm that electrochemistry in ionic liquids is excellently suited to the synthesis of high-quality semiconductor nanostructures. [ABSTRACT FROM AUTHOR]

Ionic liquids are room-temperature molten salts, composed mostly of organic ions that may undergo almost unlimited structural variations. This review covers the newest aspects of ionic liquids in applications where their ion conductivity is exploited; as electrochemical solvents for metal/semiconductor electrodeposition, and as batteries and fuel cells where conventional media, organic solvents (in batteries) or water (in polymer-electrolyte-membrane fuel cells), fail. Biology and biomimetic processes in ionic liquids are also discussed. In these decidedly different materials, some enzymes show activity that is not exhibited in more traditional systems, creating huge potential for bioinspired catalysis and biofuel cells. Our goal in this review is to survey the recent key developments and issues within ionic-liquid research in these areas. As well as informing materials scientists, we hope to generate interest in the wider community and encourage others to make use of ionic liquids in tackling scientific challenges. [ABSTRACT FROM AUTHOR]

The article discusses the interfacial electrochemistry of ionic liquids (ILs), which are versatile materials in various fields of chemistry. Topics discussed include the ILs' electrochemical and thermal windows which make the materials a candidate for the electrodeposition of refractory metals such as tantalum and niobium, an article by Ispas and colleagues on the role of IL in the electrochemical process, and absorbing solvation layers with an atomic force microscope.

Abstract: For the purpose of obtaining micrometer thick SixGe1−x deposits, quite a long electrodeposition time was applied in ionic liquids containing GeCl4 and SiCl4. Surprisingly, it was observed that the deposit is dissolved with ongoing time, at room temperature, instead of getting thicker at a sufficiently negative electrode potential. The dissolution process was only observed in liquids with the bis(trifluoromethylsulfonyl)amide (TFSA) anion and not in liquids with the tris(pentafluoroethyl)trifluorophosphate (FAP) anion. Electrochemical and chemical experiments showed that the TFSA anion is subject to an anodic decomposition obviously promoted by the solutes SiCl4 and GeCl4. The decomposition products of the TFSA anion seem to oxidize the SixGe1−x deposit chemically. These results, among others, show that the often reported superior chemical and electrochemical stability of some ionic liquids has to be handled with care: the stability limits can be significantly altered by e.g. the type of dissolved species. [Copyright &y& Elsevier]

Poly(3-methylthiophene) (PMeT) is considered a promising conductive polymer for applications in electrochromic displays due to its red to blue multi-color switch as well as low cost. However, the non-uniformity of the films caused by high electrochemical polymerization potentials during electrodeposition and the rapid electrochemical stability decay caused by weak adhesion limits its practical application. In this study, a new pre-nucleation electrodeposition method is developed to synthesize PMeT film. The nucleation grown progress is investigated by electrochemical fitting tests and scanning electron microscopy. Compared with a directly grown film, the pre-nucleation PMeT film presents excellent electrochromic EC transmittance modulation of 75% at wavelength of 1050nm, and sustains a transmittance modulation of about 91 % after 400 cycles. This was the result of enhanced uniformity and adhesion from the pre-nucleation method. The surface uniformity and roughness of PMeT films were analyzed by optical microscopy and atomic force microscopy measurements. After controlling thickness using this method, the PMeT films exhibited multiple transmittance change and red–green–blue color change. [ABSTRACT FROM AUTHOR]

Abstract: A simple and fast technique to grow free standing, open ended germanium nanotubes is demonstrated using template assisted electrodeposition from a room temperature ionic liquid. Germanium nanotubes as long as 2μm could be grown using this technique. We also show the possibility for the growth of core-shell structures. The technique demonstrated is not limited to the growth of Ge, but can be extended to grow other semiconductor nanotubes and core-shell structures. [Copyright &y& Elsevier]

In this paper we report on the electrodeposition of lithium on a polystyrene sphere modified electrode from an ionic liquid. By a simple dipping process, polystyrene (PS) spheres with an average diameter of 600 nm arrange in a hexagonal close packed structure onto an electrode surface. Surprisingly, lithium does not grow uniformly from the electrode surface to the electrolyte within the voids of the PS structure. Depending on the experimental conditions a more or less good inverse opal structure made of lithium, lithium spheres or hollow lithium half-spheres can be obtained showing that the growth of lithium in the employed ionic liquid is more complicated than expected. Somehow lithium tends to push away the PS spheres during growth. Applying a slight mechanical pressure on the PS spheres during deposition improves the growth within the voids of the opal structure. Despite this complicated behaviour the PS opal structure seems to suppress a vertical dendritic growth, thus, a lithium/PS composite electrode or other lithium/polymer composite electrodes might be of some interest in rechargeable lithium metal microbatteries where a dendritic vertical growth has to be avoided. In this paper, it is shown that lithium deposition in a polystyrene sphere opal structure can lead to hollow spheres or to a regular macroporous structure, depending on the experimental conditions. [ABSTRACT FROM AUTHOR]