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1.
The electrochemical immobilization of redox active molecule based ionic liquid onto glassy carbon electrode has been performed. 1-Nitrophenylethyl-3-methylferrocenylimidazolium bis(trifluoromethylsulfonyl)imide was synthesized and characterized by electrochemistry showing the presence of two redox couples. Following that, the electrochemical reduction of this molecule in acidic media containing sodium nitrite leads to the in situ formation of the corresponding diazonium, in the vicinity of the electrode, and subsequently the grafting of redox based ionic liquid molecule onto the electrode surface. The surface analysis of the attached layer confirms the formation of organic thin film strongly attached to the electrode surface, and evidences the presence of the components of the imidazolium ring, ferrocenyl unit, and TFSI anion. In addition, the modified electrode was electrochemically characterized by following the electrochemical signal of the attached ferrocenyl unit. Finally, the electrochemical reversible wettability of the modified electrode upon oxidation and reduction process was demonstrated. 相似文献
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In this study, the redox active molecule N-ferrocenylmethyl-N-propargylimidazolium bromide was immobilized onto the surface of an electrode. The surface modification was performed by coupling the electrochemical reduction of the 4-azidophenyldiazonium generated in situ with a copper(I) catalyzed click chemistry reaction. Surface and electrochemical investigations suggest the attachment of a monolayer of redox active molecules containing an ionic liquid framework onto the electrode surface. Furthermore, scanning electrochemical microscopy studies revealed the conductive behavior of the attached ferrocenyl moieties on the ITO surface. 相似文献
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Redox-active polyelectrolyte-surfactant complexes(PSC) were prepared via the ionic self-assembly of sodium poly(styrenesulfonate) (PSS) and ferrocenyl surfactant,(11-ferrocenylundecyl)trimethylammonium bromide(FTMA) in aqueous solution. The PSS-FTMA complex exhibited an ordered interdigitated monolayer mesomorphous structure with the long period of d = 3.13 nm,and was in the ionic thermotropic liquid crystal SmA state at room temperature.Interestingly,in the solid complex, the ferrocenyl moieties formed H-aggregation showing an increase in theπ-π~* energy transfer of cyclopentadienes in the ferrocene moieties as known from the blue-shift in the UV spectrum.The complexes showed higher thermal stability compared with their components due to the ionic interaction.The PSS-FTMA film had a good redox reversibility,which promised to be used in electrochemical sensors. 相似文献
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The effects of ionic analytes on the electrochemical properties of quaternary ammonium binaphthyl salts are described in this work. The stability of the binaphthyl radicals and hence the reversibility of the electrochemical response are discussed in terms of molecular structure. The ability of azacrown derivatised binaphthyl salts to act as amperometric receptors is ascribed to the strain imparted in the cyclic ammonium ring when Li+ ions complex with them. It is also shown that the redox properties of quaternary ammonium binaphthyl salts are pH dependent in aqueous solutions, but that reversible redox properties can be observed in extremely basic solutions. The effect of anions binding to the quaternary ammonium cation can be seen in the redox properties of the binaphthyl moiety and the use of a chiral binding site for enantiomeric recognition is also demonstrated. 相似文献
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Schneider O Bund A Ispas A Borissenko N Zein El Abedin S Endres F 《The journal of physical chemistry. B》2005,109(15):7159-7168
The direct electropolymerization of benzene dissolved in the ionic liquid 1-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate was studied at room temperature applying the electrochemical quartz-crystal microbalance technique. Analysis of the damping changes showed that the Sauerbrey equation could be applied for data evaluation. In the polymer, every third to fourth benzene ring carried a positive charge in the oxidized state. During electropolymerization, some ionic liquid was absorbed in the growing polymer. The redox behavior was characterized by wide peaks typical for conducting polymers. Charge neutrality of the polymer during redox cycling was maintained by anion and cation exchange with the ionic liquid. With increasing scan rate, cation exchange became more and more important. 相似文献
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Maria Gómez-Mingot Amarnath Chellachamy Anbalagan Hyacinthe Randriamahazaka Jalal Ghilane 《中国科学:化学(英文版)》2018,61(5):598-603
Electrochemical reductive exfoliation of graphite to few layered graphene(FLG) in presence of 1-ethyl-2,3-dimethyl imidazolium bis(trifluoromethylsulfonyl) imide ionic liquid and redox ionic liquid based ferrocene has been investigated. Thus, by applying a mild negative potential(-2.7 V vs. Fc/Fc~+) to carbon electrode in ionic liquid graphene flakes could be generated. The generated materials have been characterized by X-ray photoelectron spectroscopy, Raman spectroscopy, high resolution transmission electron microscopy and atomic force microscopy. XPS and Raman analysis show that the electrochemical reductive exfoliation provides the formation of FLG. The thickness of the resulting FLG was found to be ranged between 4 and1 nm. HR-TEM images reveal the formation of few graphene layers and in some cases single graphene layer was observed.Moreover, this electrochemical route conduces to the formation of ionic liquid functionalized FLG. Finally, the reductive exfoliation was further investigated in the presence of redox ionic liquid. XPS and electrochemical measurements confirm the presence of ferrocene. 相似文献
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The electrochemical oxidation of aminomethylferrocenes in the presence of dibenzo[24]crown-8 affords pseudorotaxanes containing a ferrocenyl group in its axis moiety. The formation of the pseudorotaxanes results from formation of secondary ammonium ions by rapid electron transfer from the N atom to the initially formed Fe(III) state, followed by hydrogen atom transfer from TEMPOH to the N+*. 相似文献
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Ion transfer across the toluene|water, toluene–ionic liquid mixture|water and ionic liquid|water boundary generated by electrochemical redox reaction of tert-butylferrocene (tBuFc) was studied with the glassy carbon (GC) electrode partially covered by the organic liquid deposit and immersed in the aqueous electrolyte solution. The electrooxidation of the redox probe in toluene deposit is followed by ejection of newly formed cation into the aqueous solution. The same reaction in the toluene–ionic liquid deposit promotes anion insertion. This pathway is also found at the electrode modified with ionic liquid. 相似文献
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Wadhawan JD Wain AJ Kirkham AN Walton DJ Wood B France RR Bull SD Compton RG 《Journal of the American Chemical Society》2003,125(37):11418-11429
The electro-oxidation of electrolytically unsupported ensembles of N,N-diethyl-N',N'-dialkyl-para-phenylenediamine (DEDRPD, R = n-butyl, n-hexyl, and n-heptyl) redox liquid femtoliter volume droplets immobilized on a basal plane pyrolytic graphite electrode is reported in the presence of aqueous electrolytes. Electron transfer at these redox liquid modified electrodes is initiated at the microdroplet-electrode-electrolyte three-phase boundary. Dependent on both the lipophilicity of the redox oil and that of the aqueous electrolyte, ion uptake into or expulsion from the organic deposits is induced electrolytically. In the case of hydrophobic electrolytes, redox-active ionic liquids are synthesized, which are shown to catalyze the oxidation of l-ascorbic acid over the surface of the droplets. In contrast, the photoelectrochemical reduction of the anaesthetic reagent halothane proceeds within the droplet deposits and is mediated by the ionic liquid precursor (the DEDRPD oil). 相似文献
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Jalal Ghilane Olivier Fontaine Pascal Martin Jean-Christophe Lacroix Hyacinthe Randriamahazaka 《Electrochemistry communications》2008,10(8):1205-1209
The electrochemical reduction of noble metal electrodes in the presence of redox ionic liquid, 1-ferrocenylethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [FcEMIM][TFSI], was investigated by cyclic voltammetry. Our experiments suggest the formation of metal with negative oxidation states, in the cases of platinum and gold electrodes [Mn−, FcEMIM+]. By analogy with the previous work, the formation of these phases is concomitant with the insertion of the supporting electrolyte; which correspond in our experimental condition to the redox cation of the ionic liquid. As an exciting result, the electrochemical investigations of the reduced electrode in electrolytic solution, containing solvent and supporting electrolyte, evidence the presence of the ferrocene groups at the electrode surface. Moreover, the reduced electrode exhibits the presence of the ferrocene even after, contact with air, after ultrasound, and after physical polishing, highlighting the large stability of this organo-metallic phases formed in this media. The AFM investigations demonstrate the morphological change of the platinum surface after the reduction process. Finally, our works bring a formal electrochemical proof of the presence of the ionic liquid cation inside the electrode material after the cathodic treatment in this media. 相似文献
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Zong‐Wei Xuan Xiao‐Ying Sun Guo‐Song Jiao Zi‐Qin Zhai Wei Sun Lu‐De Lu 《中国化学会会志》2010,57(6):1262-1267
A new carbon ionic liquid paste bioelectrode was fabricated by mixing hemoglobin (Hb) with graphite powder, ionic liquid 1‐ethyl‐3‐methylimidazolium tetrafluoroborate (EMIMBF4) and liquid paraffin homogeneously. Nafion film was cast on the electrode surface to improve the stability of bioelectrode. Direct electrochemistry of Hb in the bioelectrode was carefully investigated. Cyclic voltammetric results indicated that a pair of well‐defined and quasi‐reversible electrochemical responses appeared in pH 7.0 phosphate buffer solution (PBS), indicating that direct electron transfer of Hb was realized in the modified electrode. The formal potential (E0′) was calculated as ?0.316 V (vs. SCE), which was the typical characteristic of the electrochemical reaction of heme Fe(III)/Fe(II) redox couple. Based on the cyclic voltammetric results the electrochemical parameters of the electrode reaction were calculated. This bioelectrode showed high electrocatalytic activity towards the reduction of trichloroacetic acid (TCA) with good stability and reproducibility. 相似文献
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Repeated reaction between chiral quaternary ammonium dimer and disodium disulfonate gave the ionic polymer, which contains chiral quaternary ammonium sulfonate structure as a repeating unit. This chiral ionic polymer showed an excellent catalytic activity in asymmetric alkylation reaction. With the chiral ionic polymer catalysts, high level of enantioselectivities up to 97% ee were attained. 相似文献
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Dolidze TD Khoshtariya DE Illner P van Eldik R 《Chemical communications (Cambridge, England)》2008,(18):2112-2114
Proven electrochemical approaches were applied to study heterogeneous electron transfer (ET) between selected redox couples and gold electrodes modified with alkanethiol self-assembled monolayers (SAMs), using the room-temperature ionic liquid (RTIL) [bmim][NTf2] as reaction medium; ferrocene as freely diffusing redox probe in the RTIL was tested for ET through both thin (butanethiol) and thick (dodecanethiol) assemblages at pressures up to 150 MPa; well behaved kinetic patterns and reproducibility of data were demonstrated for ET within the unique Au/SAM/RTIL arrays. 相似文献
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Stephen Fletcher Victoria Jane Black Iain Kirkpatrick Thomas Stephen Varley 《Journal of Solid State Electrochemistry》2013,17(2):327-337
In many modern technologies (such as batteries and supercapacitors), there is a strong need for redox-stable ionic liquids. Experimentally, the stability of ionic liquids can be quantified by the voltage range over which electron tunneling does not occur, but so far, quantum theory has not been applied systematically to this problem. Here, we report the electrochemical reduction of a series of quaternary ammonium cations in the presence of bis(trifluoromethylsulfonyl)imide (TFSI) anions and use nonadiabatic electron transfer theory to explicate the results. We find that increasing the chain length of the alkyl groups confers improved chemical inertness at all accessible temperatures. Simultaneously, decreasing the symmetry of the quaternary ammonium cations lowers the melting points of the corresponding ionic liquids, in two cases yielding highly inert solvents at room temperature. These are called hexyltriethylammonium TFSI (HTE-TFSI) and butyltrimethylammonium TFSI (BTM-TFSI). Indeed, the latter are two of the most redox-stable solvents in the history of electrochemistry. To gain insight into their properties, very high precision electrical conductivity measurements have been carried out in the range +20 °C to +190 °C. In both cases, the data conform to the Vogel-Tammann-Fulcher (VTF) equation with “six nines” precision (R 2?>?0.999999). The critical temperature for the onset of conductivity coincides with the glass transition temperature T g. This is compelling evidence that ionic liquids are, in fact, softened glasses. Finally, by focusing on the previously unsuspected connection between the molecular degrees of freedom of ionic liquids and their bulk conductivities, we are able to propose a new theory of the glass transition. This should have utility far beyond ionic liquids, in areas as diverse as glassy metals and polymer science. 相似文献
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Niedziolka J Rozniecka E Stafiej J Sirieix-Plenet J Gaillon L di Caprio D Opallo M 《Chemical communications (Cambridge, England)》2005,(23):2954-2956
Ion transfer across the boundary formed at an ionic liquid drop deposited on an electrode immersed in aqueous solution, generated by electrochemical redox reaction at the electrode-ionic liquid interface, is studied to obtain information about the ability of anions to be transferred into a room temperature ionic liquid. 相似文献
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Mono‐ and Dinuclear Ferrocenyl Ionic Compounds with Polycyano Anions. Characterization,Migration, and Catalytic Effects on Thermal Decomposition of Energetic Compounds 下载免费PDF全文
Ersha Shao Dongdong Li Jizhen Li Guofang Zhang Weiqiang Zhang Ziwei Gao 《无机化学与普通化学杂志》2016,642(16):871-881
Neutral ferrocene‐based burning rate (BR) catalysts show strong migration trends and volatility during long‐time storage and curing of the composite solid propellants. To reduce these disadvantages thirty‐two ferrocenyl quaternary ammonium compounds, paired with polycyano anions, were synthesized and characterized by 1H NMR, 13C NMR, and UV/Vis spectroscopy, as well as elemental analysis. Additionally, crystal structures of eight compounds were confirmed by single‐crystal X‐ray diffraction. TG and DSC analyses indicated that the compounds containing 1,1,2,3,3‐pentacyanopropenide anions show high thermal stability. Cyclic voltammetry studies suggested that they are quasi‐reversible or irreversible redox systems. Anti‐migration tests verified that the tested compounds show very low migration tendency and some of them exhibit no migration after 30 days aging at 70 °C. Their catalytic efficiency in the thermal decomposition of ammonium perchlorate (AP), 1,3,5‐trinitro‐1,3,5‐triazacyclohexane (RDX), and 1,2,5,7‐tetranitro‐1,3,5,7‐tetraazacyclooctane (HMX) were examined by DSC analyses. The results revealed that most of the compounds exhibit distinct effects on the thermal degradation of AP and RDX. Two compounds have good catalytic ability in the thermal decomposition of HMX, representing rare examples of the reported ferrocenyl ionic compounds, which display catalytic property during combustion of HMX. 相似文献
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《中国化学会会志》2012,59(7)
Repeated reaction between chiral quaternary ammonium halide dimer and disodium disulfonate gave the ionic polymer, which contains chiral quaternary ammonium sulfonate structure as a repeating unit. This chiral ionic polymer showed an excellent catalytic activity in asymmetric benzylation reaction. With the chiral ionic polymer catalysts, high level of enantioselectivities up to 97% ee were attained. For more details on this figure, please see pp 815~821 in this issue. 相似文献