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1.
Poly-3-methylthiophene (P3MT) was synthesized in the room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6) by constant potential and constant current respectively. The structure and morphology of P3MT films were characterized by FTIR spectrum and SEM. The undoped (reduction) and doped (oxidation) forms of P3MT film prepared in ionic liquid were reversible and stable. The P3MT film has strong characteristics of electrocatalytic oxidation of ascorbic acid and can separate the oxidation peaks of ascorbic acid and dopamine. Two methods of potential steps were used to observe the response time of the film and the film was found to have perfect electrochromic response.  相似文献   

2.
Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]Cl-AlCl3 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer material, was obtained by recrystalling the reaction mixture with aether and was determined by GC/MS, 1↑HNMR and FTIR analysis. The influences of various parameters, such as the contents of AlCl3 in [Emim]Cl-AlCl3, the amount of acylation agent, amount of [Emim]Cl-AlCl3, reaction temperature and reaction time were investigated. The optimum conditions were as follows: the molar fraction of AlCl3 in ionic liquid [x(AlCl3)] being 0.67, molar ratio of ionic liquid to anthracene being 2:1, molar ratio of oxalyl chloride to anthracene being 2:1, reaction temperature being 40℃ and reaction time being 6h. Under above conditions, the yield and selectivity of 1,2-aceanthrylenedione can reach 91.5% and 98.3% respectively. Further more, [Emim]Cl-AlCl3 ionic liquid, compared with metal halides such as AlCl3, was found to catalyze the reaction as a novel environmental friendly catalyst and solvent and can be reused.  相似文献   

3.
A novel analytical method was developed for determining morpholinium cations lacking ultraviolet absorption groups.This determination was carried out by high performance liquid chromatographyindirect ultraviolet(HPLC-1UV) detection using imidazolium ionic liquid as background absorption reagents,and imidazolium ionic liquid aq.soln.-organic solvent as mobile phase by a reversed-phase C18 column.The background ultraviolet absorption reagents,imidazolium ionic liquids and organic solvents were investigated.The imidazolium ionic liquid in the mobile phase is not only the background ultraviolet absorption reagent for IUV,but also an active component to improve the separation of morpholinium cations.It was found that morpholinium cations could be adequately determined when0.5 mmol/L 1-ethyl-3-methylimidazolium tetrafluoroborate aq.soln./methanol(80:20,v/v) was used as mobile phase with an IUV detection wavelength of 210 nm.In this study,the baseline separation of Nmethyl,ethylmorpholinium cations(MEMo) and N-methyl.propylmorpholinium cations(MPMo) was successfully achieved in 8.5 min.The detection limits(S/N = 3) for MEMo and MPMo were 0.15 and0.29 mg/L,respectively.This simple and practical method has been successfully applied to the determination of two morpholinium ionic liquids synthesized by the chemistry laboratory.  相似文献   

4.
In this work, a new microextraction method termed ionic liquid based dispersive liquid-liquid microextraction (IL-DLLME) was demonstrated for the extraction of 2-methylaniline, 4-chloroaniline, 1-naphthylamine and 4-aminobiphenyl in aqueous matrices. After extraction the ionic liquid (IL) phase was injected directly into the high performance liquid chromatography (HPLC) system for determination. Some parameters that might affect the extraction efficiency were optimized. Under the optimum conditions, good linear relationship, sensitivity and reproducibility were obtained. The limits of detection (LOD, S/N = 3) for the four analytes were in the range of 0.45-2.6 μg L^-1. The relative standard deviations (R.S.D., n = 6) were in the range of 6.2-9.8%. This method was applied for the analysis of the real water samples. The recoveries ranged from 93.4 to 106.4%. The main advantages of the method are high speed, high recovery, good repeatability and volatile organic solvent-free.  相似文献   

5.
A novel Brφnsted acid task specific ionic liquid 1-ethylbenzimidazolium tetrafluoroborate ([Hebim]BF4) with functional benzimidazolium cation was synthesized and characterized by ^1H NMR, IR, MS spectra and elemental analysis. This novel ionic liquid was successfully used as dual solvent-catalyst for the synthesis of arylic esters. Higher yields were obtained in the presence of [Hebim]BF4 in comparison with other imidazolium ionic liquids because of the good solubility of the aromatic alcohols and aromatic carboxylic acids in [Hebim]BF4. The product could be separated conveniently from the reaction system, and the ionic liquid could be easily reused after removal of water under vacuum. After 10 times reuse, the selectivity of the ester was still 100%.  相似文献   

6.
The biocompatiable and low-toxic poly(thiophene-3-acetic acid)(PTAA) matrix was successfully electrosynthesized in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate(BmimPF6) in comparison with the electrosynthesis of PTAA matrix in acetonitrile(ACN).Ascorbate oxidase(AO) was used as a model for the development and application of biosensor.Vitamin C(VC) biosensors were facilely fabricated by the covalent immobilization of AO molecules on PTAA matrices electrosynthesized in ACN containing tetrabutylammonium tetrafluoroborate and BmimPF6, respectively.Electrochemical impedance spectroscopy,scanning electron microscopy and FTIR spectroscopy indicated that AO molecules were covalently immobilized on PTAA matrices.Parameters of the as-obtained biosensors such as working potential,pH and temperature have been optimized.The amperometric biosensor based on PTAA matrix electrosynthesized in BmimPF6 exhibited wider linear range,lower detection limit,higher sensitivity and bioaffinity,and better operational and storage stability than that electrosynthesized in ACN under optimal conditions.The as-obtained biosensor based on PTAA matrix electrosynthesized in BmimPF6 was employed for the detection of VC content in commercial juices,and the result was close to the data given by manufacturers.Excellent results indicate that the PTAA matrix electrosynthesized in ionic liquid is a promising platform for the covalent immobilization of biologically-active species and the development of biosensors.  相似文献   

7.
《天然气化学杂志》2012,(4):476-479
Promoted catalytic reaction between methanol and CO2 for dimethyl carbonate(DMC) synthesis is conducted over K2CO3/CH3 I catalyst in the presence of ionic liquid under microwave irradiation.The effect of ionic liquids incorporated with microwave irradiation on the yield of DMC is investigated.DMC was found to form at lower temperature in a relative short time,which indicated an enhanced catalytic process by ionic liquid.Among the ionic liquids used,1-butyl-3-methylimidazolium chloride is the most effective promoter.Density functional theory calculations indicate that CO2 bond lengths and angles changed due to the molecular interaction of ionic liquid and CO2,resulting in the activation of CO2 molecules and consequently the acceleration of reaction rate.  相似文献   

8.
Ionic liquid gel polymers have widely been used as the electrolytes in all-solid-state supercapacitors, but they suffer from low ionic conductivity and poor electrochemical performance. Arc discharge is a fast, low-cost and scalable method to prepare multi-layered graphene nanosheets, and as-made graphene nanosheets (denoted as ad-GNSs) with few defects, high electrical conductivity and high thermal stability should be favorable conductive additive materials. Here, a novel ionic liquid gel polymer electrolyte based on an ionic liquid (EM1MNTF2) and an copolymer (P(VDF-HFP)) was modified by the addition of ad-GNSs as an ionic conducting promoter. This modified gel electrolyte shows excellent thermal stability up to 400 ℃ and a wide electrochemical window of 3 V. An all-solid-state supercapacitor based on commercial activated carbon was fabricated using this modified ionic liquid gel polymer electrolyte, which shows obviously improved electrochemical behaviors compared with those of the corresponding all-solid-state supercapacitor using pure ionic liquid gel polymer electrolyte. Specially, smaller internal resistance, higher specific capacitance, better rate performance and cycling stability are achieved. These results indicate that the ionic liquid gel polymers modified by ad-GNSs would be promising and suitable gel electrolytes for high performance all-solid-state electrochemical devices.  相似文献   

9.
Electrochemical polymerization of aniline and 3-methylthiophene has been accomplished in 1-methylimidazium tetrafluoroborate (HMIMBF4) ionic liquid. Homopolymer and copolymers of aniline and 3-methylthiophene were obtained successfully. The copolymer was studied by cyclic voltammetry and electrochemical impedance spectroscopy. The formation of copolymer has been confirmed by FT-IR and UV spectra. The atomic force microscope (AFM) was used for microstructural analysis. Both the homopolymer and the copolymer had the catalytic activity for the hydroquinone.  相似文献   

10.
Ionic liquid,1-butyl-3-methylimidazolium acetate(BMImAc),was used in the electrochemical reduction of nitrobenzene.The electro-reduction of nitrobenzene on platinum electrode was studied by cyclic voltammetry(CV),in situ Fourier transform infrared(FTIR) spectroscopy and constant-potential electrolysis.The experimental results show that electrochemical reduction process of nitrobenzene was controlled by diffusion,the main reduction product was azobenzen at-1.45 V,and the influences of scan rate and temperature on the electrochemical behaviors were obviously.A reduction mechanism of nitrobenzene in an ionic liquid was a probable ‘nitrobenzene→nitrosobenzene→azobenzene→aniline' main reductive reaction route.  相似文献   

11.
在干燥氩气氛下, 用等摩尔的高纯无水GaCl3和[C2mim][Cl](氯化1-甲基-3-乙基咪唑)直接搅拌混合, 制备了淡黄色透明的的离子液体[C2mim][GaCl4] (1-ethyl-3-methylimidazolium chlorogallate) . 在298.15 K下, 利用具有恒温环境的溶解反应热量计, 测定了这种离子液体的不同浓度摩尔溶解焓 . 针对[C2mim][GaCl4]溶解于水后即分解的特点, 在Pitzer电解质溶液理论基础上, 提出了确定这种离子液体标准摩尔溶解焓的新方法, 得到了[C2mim][GaCl4]在水中的标准摩尔溶解焓, =-132 kJ•mol-1, 以及Pitzer焓参数组合: =-0.1373076和 =0.3484209. 借助热力学循环和Glasser离子液体晶格能理论, 用Ga3+, Cl-和[C2mim]—的离子水化焓数据以及本文得到的[C2mim][GaCl4]标准摩尔溶解焓, 估算了配离子4Cl-(g)解离成Ga3+(g)和4Cl-(g)的解离焓ΔHdis([GaCl4]-)≈5855 kJ•mol-1. 这个结果揭示了离子液体[C2mim][GaCl4]的标准摩尔溶解焓绝对值并不很大的原因, 即是很大的离子水化焓被很大的[GaCl4]-(g)的解离焓相互抵消了.  相似文献   

12.
Following the development in the synthesis of subvalent cluster compounds, we report on the use of three different classes of room-temperature ionic liquids for the synthesis of the pentabismuth-tris(tetragallate) salt, Bi5[GaCl4]3, characterized by X-ray diffraction. The Bi5[GaCl4]3 salt was prepared by reduction of BiCl3 using gallium metal in ionic liquid reaction media containing a strong Lewis acid, GaCl3. The ionic liquids; trihexyltetradecyl phosphonium chloride [Th-Td-P+]Cl?, 1-dodecyl-3-methylimidazolium chloride [Dod-Me-Im+]Cl? and N-butyl-N-methylpyrrolidinium chloride [Bu-Me-Pyrr+]Cl? from three of the main classes of ionic liquids were used in synthesis. Reactions using ionic liquids composed of the trihexyltetradecyl phosphonium cation [Th-Td-P+] and the anions; tetrafluoroborate [BF4 ?], bis(trifluoro-methyl sulfonyl) imide [(Tf)2N?] and hexafluorophosphate [PF6 ?] were also investigated.  相似文献   

13.
Aqueous–ionic liquid (A–IL) biphasic systems have been examined in terms of deuterated water, acid, and IL cation and anion mutual solubilities in the upper (water‐rich, in mole fraction) and lower phase of aqueous/IL biphasic systems at ambient temperature. The biphasic mixtures were composed of deuterated acids of various concentrations (mainly DCl, DNO3, and DClO4 from 10?2 to 10?4 M ) and five ionic liquids of the imidazolium family with a hydrophobic anion (CF3SO2)2N?, that is, [C1Cnim][Tf2N], (n=2, 4, 6, 8 and 10). The analytical techniques applied were 1H NMR, 19F NMR, Karl–Fischer titration, pH potentiometry for IL cations and anions, and water and acid determination. The effects of the ionic strength (μ=0.1 M NaCl and NaNO3 as well as μ=0.1 M , 0.2 M and 0.4 M NaClO4, according to the investigated acid), the nature of the IL cation, and the nature of the mineral acid on the solubilities of the (D2O, D+, Tf2N?, C1Cnim+) entities in the lower or upper phases were determined. The addition of sodium perchlorate was found to enhance the Tf2N? solubility while inhibiting the solubility of the ionic liquid cation. Differences in IL cation and anion solubilities of up to 42 mM were evidenced. The consequences for the characterization of the aqueous biphasic system, the solvent extraction process of the metal ions, and the ecological impact of the ILs are discussed.  相似文献   

14.
A novel biopolymer/room‐temperature ionic liquid composite film based on carrageenan, room temperature ionic liquid (IL) [1‐butyl‐3‐methylimidazolium tetra?uoroborate ([BMIM]BF4)] was explored for immobilization of hemoglobin (Hb) and construction of biosensor. Direct electrochemistry and electrocatalytic behaviors of Hb entrapped in the IL‐carrageenan composite ?lm on the surface of glassy carbon electrode (GCE) were investigated. UV‐vis spectroscopy demonstrated that Hb in the IL‐carrageenan composite ?lm could retain its native secondary structure. A pair of well‐de?ned redox peaks of Hb was obtained at the Hb‐IL‐carrageenan composite ?lm modi?ed electrode through direct electron transfer between the protein and the underlying electrode. The heterogeneous electron transfer rate constant (ks) was 2.02 s?1, indicating great facilitation of the electron transfer between Hb and IL‐carrageenan composite film modi?ed electrode. The modi?ed electrode showed excellent electrocatalytic activity toward reduction of hydrogen peroxide with a linear range of 5.0×10?6 to 1.5×10?4 mol/L and the detection limit was 2.12×10?7 mol/L (S/N=3). The apparent Michaelis‐Menten constant KMapp for hydrogen peroxide was estimated to be 0.02 mmol/L, indicating that the biosensor possessed high af?nity to hydrogen peroxide. In addition, the proposed biosensor showed good reproducibility and stability.  相似文献   

15.
Herein, we introduce a facile, user‐ and environmentally friendly (n‐octanol‐induced) oleic acid (OA)/ionic liquid (IL) two‐phase system for the phase‐ and size‐controllable synthesis of water‐soluble hexagonal rare earth (RE=La, Gd, and Y) fluoride nanocrystals with uniform morphologies (mainly spheres and elongated particles) and small sizes (<50 nm). The unique role of the IL 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BmimPF6) and n‐octanol in modulating the phase structure and particle size are discussed in detail. More importantly, the mechanism of the (n‐octanol‐induced) OA/IL two‐phase system, the formation of the RE fluoride nanocrystals, and the distinctive size‐ and morphology‐controlling capacity of the system are presented. BmimPF6 is versatile in term of crystal‐phase manipulation, size and shape maintenance, and providing water solubility in a one‐step reaction. The luminescent properties of Er3+‐, Ho3+‐, and Tm3+‐doped LaF3, NaGdF4, and NaYF4 nanocrystals were also studied. It is worth noting that the as‐prepared products can be directly dispersed in water due to the hydrophilic property of Bmim+ (cationic part of the IL) as a capping agent. This advantageous feature has made the IL‐capped products favorable in facile surface modifications, such as the classic Stober method. Finally, the cytotoxicity evaluation of NaYF4:Yb,Er nanocrystals before and after silica coating was conducted for further biological applications.  相似文献   

16.
The chemistry of polyphosphorus cations has rapidly developed in recent years, but their coordination behavior has remained mostly unexplored. Herein, we describe the reactivity of [P5R2]+ cations with cyclopentadienyl metal complexes. The reaction of [CpArFe(μ‐Br)]2 (CpAr=C5(C6H4‐4‐Et)5) with [P5R2][GaCl4] (R=iPr and 2,4,6‐Me3C6H2 (Mes)) afforded bicyclo[1.1.0]pentaphosphanes ( 1‐R , R=iPr and Mes), showing an unsymmetric “butterfly” structure. The same products 1‐R were formed from K[CpAr] and [P5R2][GaCl4]. The cationic complexes [CpArCo(η4‐P5R2)][GaCl4] ( 2‐R [GaCl4], R=iPr and Cy) and [(CpArNi)23:3‐P5R2)][GaCl4] ( 3‐R [GaCl4]) were obtained from [P5R2][GaCl4] and [CpArM(μ‐Br)]2 (M=Co and Ni) as well as by using low‐valent “CpArMI” sources. Anion metathesis of 2‐R [GaCl4] and 3‐R [GaCl4] was achieved with Na[BArF24]. The P5 framework of the resulting salts 2‐R [BArF24] can be further functionalized with nucleophiles. Thus reactions with [Et4N]X (X=CN and Cl) give unprecedented cyano‐ and chloro‐functionalized complexes, while organo‐functionalization was achieved with CyMgCl.  相似文献   

17.
A dicationic ruthenium–alkylidene complex [Ru(dmf)3(IMesH2)(?CH‐2‐(2‐PrO)‐C6H4)][(BF4)2] ( 1 ; IMesH2=1,3‐dimesitylimidazolin‐2‐ylidene) has been prepared and used in continuous metathesis reactions by exploiting supported ionic‐liquid phase (SILP) technology. For these purposes, ring‐opening metathesis polymerization (ROMP)‐derived monoliths were prepared from norborn‐2‐ene, tris(norborn‐5‐ene‐2‐ylmethyloxy)methylsilane, and [RuCl2(PCy3)2(CHPh)] (Cy=cyclohexyl) in the presence of 2‐propanol and toluene and surface grafted with norborn‐5‐en‐2‐ylmethyl‐N,N,N‐trimethylammonium tetrafluoroborate ([NBE‐CH2‐NMe3][BF4]). Subsequent immobilization of the ionic liquid (IL), 1‐butyl‐2,3‐dimethylimidazolium tetrafluoroborate ([BDMIM][BF4]), containing ionic catalyst 1 created the SILP catalyst. The use of a second liquid transport phase, which contained the substrate and was immiscible with the IL, allowed continuous metathesis reactions to be realized. High turnover numbers (TONs) of up to 3700 obtained in organic solvents for the ring‐closing metathesis (RCM) of, for example, N,N‐diallyltrifluoroacetamide, diethyl diallylmalonate, diethyl di(methallyl)malonate, tert‐butyl‐N,N‐diallylcarbamate, N,N‐diallylacetamide, diphenyldiallylsilane, and 1,7‐octadiene, as well as in the self‐metathesis of methyl oleate, could be further increased by using biphasic conditions with [BDMIM][BF4]/heptane. Under continuous SILP conditions, TONs up to 900 were observed. Due to the ionic character of the initiator, catalyst leaching into the transport phase was very low (<0.1 %). Finally, the IL can, together with decomposed catalyst, be removed from the monolithic support by flushing with methanol. Upon reloading with [BDMIM][BF4]/ 1 , the recycled support material again qualified for utilization in continuous metathesis reactions.  相似文献   

18.
An ionic liquid (IL) was prepared by directly mixing InCl3 and 1-methyl-3-butylimidazolium chloride(BMIC) with molar ratio 1:1 under dry argon atmosphere. The densities, and surface tension of pure IL were determined at temperature range of (278.15 to 343.15±0.1K). The properties for ionic liquid based on group III were discussed using Glasser’s theory. The standard entropy, the surface energy and the crystal energy of ionic liquid were calculated, respectively. The crystal energy of ionic liquid is much lower than ionic solid and this is the underlying reason for forming ionic liquid at room temperature. In addition, a new theoretical model of IL, that is interstice model, was applied to calculate the thermal expansion coefficient of BMIInCl4. The order of magnitude for the thermal expansion coefficient, a, calculated by the theoretical model is in good agreement with experimental value. The result shows that there is much reasonableness for the interstice model of ionic liquid. __________ Translated from Chemical Journal of Chinese University, 2005, 26(10)(in Chinese)  相似文献   

19.
Gold nanoparticles (Au‐NPs) were reproducibly obtained by thermal, photolytic, or microwave‐assisted decomposition/reduction under argon from Au(CO)Cl or KAuCl4 in the presence of n‐butylimidazol dispersed in the ionic liquids (ILs) BMIm+BF4?, BMIm+OTf?, or BtMA+NTf2? (BMIm+=n‐butylmethylimidazolium, BtMA+=n‐butyltrimethylammonium, OTf?=?O3SCF3, NTf2?=?N(O2SCF3)2). The ultra small and uniform nanoparticles of about 1–2 nm diameter were produced in BMIm+BF4? and increased in size with the molecular volume of the ionic liquid anion used in BMIm+OTf? and BtMA+NTf2?. Under argon the Au‐NP/IL dispersion is stable without any additional stabilizers or capping molecules. From the ionic liquids, the gold nanoparticles can be functionalized with organic thiol ligands, transferred, and stabilized in different polar and nonpolar organic solvents. Au‐NPs can also be brought onto and stabilized by interaction with a polytetrafluoroethylene (PTFE, Teflon) surface. Density functional theory (DFT) calculations favor interactions between IL anions instead of IL cations. This suggests a Au???F interaction and anionic Aun stabilization in fluorine‐containing ILs. The 19F NMR signal in BMIm+BF4? shows a small Au‐NP concentration‐dependent shift. Characterization of the dispersed and deposited gold nanoparticles was done by transmission electron microscopy (TEM/HRTEM), transmission electron diffraction (TED), dynamic light scattering (DLS), UV/Vis absorbance spectroscopy, scanning electron microscopy (SEM), electron spin resonance (ESR), and electron probe micro analyses (EPM, SEM/EDX).  相似文献   

20.
Mercury(I) chloride reacts with gallium(III) chloride in benzene/1, 2‐dichlorobenzene solution to give the binuclear compound Hg2(GaCl4)2 ( 1 ). Reduction of mercury(I) chloride with mercury in gallium(III) chloride‐benzene mixture leads to the trinuclear compound Hg3(GaCl4)2 ( 2 ). The crystal structures of 1 and 2 were determined by single‐crystal X‐ray diffraction {Hg2(GaCl4)2: triclinic, P1¯, a = 645.21(3), b = 654.44(3), c = 927.17(7) pm, α = 83.526(2)°, β = 74.915(2)°, γ = 61.863(3)°; Hg3(GaCl4)2: monoclinic, P21/c, a = 715.79(1), b = 1501.59(4), c = 1421.43(4) pm, β = 98.9798(9)°}.  相似文献   

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