Room-temperature ionic liquids nanoparticles

Whereas, Goharshadi et al. [16] have synthesized the ZnO nanoparticles of 60 nm (Fig. 8.4.) using a room temperature ionic liquid, l-hexyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide, Formation of ZnO was not observed when the ionic liquid was replaced by water. Also, in the absence of ultrasound, formation of ZnO was not observed which is very similar to the one as proposed in the previous case of ZnO dendritic nanostructures. 

The electrodeposition of silver from chloroaluminate ionic liquids has been studied by several authors [45-47], Katayama et al. [48] reported that the room-temperature ionic liquid l-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM]BF4) is applicable as an alternative electroplating bath for silver. The ionic liquid [EMIM]BF4 is superior to the chloroaluminate systems since the electrodeposition of silver can be performed without contamination of aluminum. Electrodeposition of silver in the ionic liquids 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) and l-butyl-3-methylimidazoliumhexafluorophosphate was also reported [49], Recently we showed that isolated silver nanoparticles can be deposited on the surface of the ionic liquid Tbutyl-3-methylimidazolium trifluoromethylsulfonate ([BMIMJTfO) by electrochemical reduction with free electrons from low-temperature plasma [50] (see Chapter 10). This unusual reaction represents a novel electrochemical process, leading to the reproducible growth of nanoscale materials. In our experience silver is quite easy to deposit in many air- and water-stable ionic liquids. 

Sanes J, Carrion FJ, Bermudez MD (2010) Effect of the addition of room temperature ionic liquid and ZnO nanoparticles on the wear and scratch resistance of epoxy resin. Wear 268 1295-1302... 

The same methodology could be applied to platinum using Pt2(dba)3 and various room-temperature ionic liquids, and led to metallic Pt nanoparticles with a mean size near 2.0-2.5 nm (Scheme 6). " The isolated Pt(0) nanoparticles could be redispersed in the ionic liquid or in acetone or else used in solventless conditions for liquid-liquid biphasic,... 

Chen, S., Liu, Y., and Wu, G. 2005. Stabilized and size-tunable gold nanoparticles formed in a quaternary ammonium-based room-temperature ionic liquid under y-irradiation. Nanotechnology 16 2360-2364. 

Zhang D, Chang W, Okajima T, Ohsaka T (2011) Electrodeposition of platimun nanoparticles in a room-temperature ionic liquid. Langmuir 27 14662-14668... 

Zhang D, Okajima T, Lu D, Ohsaka T (2013) Electroless deposition of platinum nanoparticles in room-temperature ionic liquids. Langmuir 29 11931-11940... 

Magnetic Nanoparticles Using Room-Temperature Ionic Liquids, Chem. Eur.. vol. 12, pp. 3798. 

The sharp double-barrel pipettes are then filled with electrolyte solution (typically aqueous salt solutions between 1 and 100 mM ionic strength), which can also contain other species (such as redox mediators or a nanoparticle dispersion). We have also successfully employed room temperature ionic liquids (RTILs) in SECCM. The electrolyte solution naturally forms a small liquid meniscus over the end of the pipette, connecting the two barrels. QRCEs are inserted into each barrel, and a conductance cell is formed between the QRCEs and across the liquid meniscus. Ag/ AgCl and Pd-H2 electrodes have been used as QRCEs. To help confine an aqueous meniscus, the outside walls of the pipette are often salinized using dimethyldichlorosilane [Si(CH3)2Cl2]. ... 

Mu, X. Evans, D. G. Kou,Y. (2004) A general method for preparation of PVP-stabilized noble metal nanoparticles in room temperature ionic liquids. Catal. Lett. 97, 3-4, 151-154,1011-372X... 

Nanoparticle Preparation in Room-Temperature Ionic Liquid under Vacuum Condition... 

Tsuda, T., Seino, S. Kuwabata, S. (2009a). Gold nanoparticles prepared with a room-temperature ionic liquid-irradiation method, Chem. Commun. 6792-6794. 

Tsuda, T., Yoshii, K, Torimoto, T. Kuwabata, S. (2010b). Oxygen reduction catalytic ability of platinum nanoparticles prepared by room-temperature ionic liquid-sputtering method, /, Power Sources, 195 5980-5985. 

Cadmium selenide (CdSe) is an n-type semiconductor with a band gap of 1.74 eV at room temperature. The semiconductor nanoparticles with sizes below 100 nm are technologically interesting due to a quantum confinement effect. It has been reported that thin film of CdSe with a band gap of 1.8 eV can be made electrochemically on FTO-coated glass in ChCl/urea ionic liquid containing CdCl2 and 0.1 M Na2S03 (aq.) [24]. Similar to ZnS, the authors presented only a photocurrent spectrum of electrochemically made CdSe. A detailed characterization of CdSe deposits was not shown. 

Similarly, Kou et al. published the synthesis of PVP-stabilized noble-metal nanoparticles in ionic liquids BMI PF6 at room temperature [76]. The metal nanoparticles (Pt, Pd, Rh) were produced by reduction of the corresponding metal halide salts in the presence of PVP into a refluxing ethanol-water solution. After evaporation to dryness the residue was redissolved in methanol and the solution added to the ionic liquid. The methanol was then removed by evaporation to give the ionic liquid-immobilized nanoparticles. These nanoparticles were very stable. TEM ob-... 

Recently, Dupont and coworkers described the use of room-temperature imi-dazolium ionic liquids for the formation and stabilization of transition-metal nanoparticles. The potential interest in the use of ionic liquids is to promote a bi-phasic organic-organic catalytic system for a recycling process. The mixture forms a two-phase system consisting of a lower phase which contains the nanocatalyst in the ionic liquid, and an upper phase which contains the organic products. Rhodium and iridium [105], platinum [73] or ruthenium [74] nanoparticles were prepared from various salts or organometallic precursors in dry 1-bu-tyl-3-methylimidazolium hexafluorophosphate (BMI PF6) ionic liquid under hydrogen pressure (4 bar) at 75 °C. Nanoparticles with a mean diameter of 2-3 nm... 

Currently silicon is still one of the most important semiconductors as it is the basis of any computer chip. It exhibits an indirect band gap of 1.1 eV at room temperature in the microcrystalline phase. Similar to Ge, silicon nanoparticles show a size-dependent photoluminescence. It was reported by Katayama el al. that a thin Si layer can be electrodeposited in l-ethyl-3-methylimidazolium hexafluorosilicate at 90 °C [44], However, upon exposure to air the deposit reacted completely to SiC>2, which makes it difficult to decide whether the deposit was semiconducting or not. Recently, we showed for the first time that silicon can be well electrodeposited from SiCU in the air and water stable ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide ([BMPJTfiN) [45, 46]. This ionic liquid can be... 

Fig. 10.8 Schematic experimental set-up for the deposition of metal nanoparticles by plasma electrochemical reduction of a metal salt dissolved in an ionic liquid at room temperature.

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