Development of clean desulfurization process that combines both efficient and environmentally friendly remains a significant challenge for diesel production.The photocatalytic oxidation desulfurization technology is r...Development of clean desulfurization process that combines both efficient and environmentally friendly remains a significant challenge for diesel production.The photocatalytic oxidation desulfurization technology is regarded as a promising process depending on the superior electron transfer and visible light utilization of photocatalyst.Herein,the nonstoichiometry MoO_(3-x)with outstanding photoresponse ability is prepared and modified by imidazole-based ionic liquid[C_(12)mim]Cl to upgrade electronic structure.The interface H-bonding between MoO_(3-x)and[C_(12)mim]Cl regard as electronic transfer channel and the recombination of e^(-)-h^(+)pairs is effectively inhibited with the modification of[C_(12)mim]Cl.Deep desulfurization rate of 96.6%can be reached within 60 min and the MoO_(3-x)/[C_(12)mim]Cl(MoC_(12))photocatalyst demonstrated outstanding cyclic stability within 7 cycles in an extraction coupled photocatalytic oxidation desulfurization(ECPODS)system.The study provides a new perspective on enhancing photocatalytic desulfurization through defect engineering and surface modification.展开更多
Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials ...Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials of SPEs due to its remarkable compatibility with lithium metal anodes(LMAs)and suitability for in-situ polymerization.However,poor thermal stability,insufficient ionic conductivity and narrow electrochemical stability window(ESW)hinder its further application in lithium metal batteries(LMBs).To ameliorate these problems,we have successfully synthesized a polymerized-ionic-liquid(PIL)monomer named DIMTFSI by modifying DOL with imidazolium cation coupled with TFSI^(-)anion,which simultaneously inherits the lipophilicity of DOL,high ionic conductivity of imidazole,and excellent stability of PILs.Then the tridentate crosslinker trimethylolpropane tris[3-(2-methyl-1-aziridine)propionate](TTMAP)was introduced to regulate the excessive Li^(+)-O coordination and prepare a flame-retardant SPE(DT-SPE)with prominent thermal stability,wide ESW,high ionic conductivity and abundant Lit transference numbers(t_(Li+)).As a result,the LiFePO_(4)|DT-SPE|Li cell exhibits a high initial discharge specific capacity of 149.60 mAh g^(-1)at 0.2C and 30℃with a capacity retention rate of 98.68%after 500 cycles.This work provides new insights into the structural design of PIL-based electrolytes for long-cycling LMBs with high safety and stability.展开更多
CeF3 and CeF3:Tb3+ nanocrystals were successfully synthesized by the ultrasound assisted ionic liquid (IL) method at room temperature. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission ...CeF3 and CeF3:Tb3+ nanocrystals were successfully synthesized by the ultrasound assisted ionic liquid (IL) method at room temperature. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), high-resolution transmission electron micrographs (HRTEM) and photoluminescence (PL) spectra were employed to characterize the nanocrystals. The results of XRD indicated that the obtained samples crystallized well with a hexagonal phase crystal structure. SEM and TEM images demonstrated that the obtained CeF3:Tb3+ nanocrystals had a discoid shapein the presence of ultrasound and IL, whereas only granular nanoparticles were obtained by magnetic stirring. The possible formation mechanisms of the crystal growth were proposed. The PL spectra of the CeF3:Tb3+ nanodisks exhibited a strong green emission when excited at 254 nm. Furthermore, the photoluminescence intensity of CeF3:Tb3+ of the discoid particles was largely improved com-pared with that of the granular nanoparticles.展开更多
Abstract The study on the catalysis of ionic liquids for alkylation of benzene with 1-octadecene to synthesize LAB (linear alkylbenzenes) was performed. The results showed that the most important factor that governe...Abstract The study on the catalysis of ionic liquids for alkylation of benzene with 1-octadecene to synthesize LAB (linear alkylbenzenes) was performed. The results showed that the most important factor that governed the conversion of olefin and selectivity of LAB was reaction temperature. Moreover, the effects of different ionic liquids and molar ratio of benzene to 1-octadecene on the conversion and selectivity were obviously in different degrees. The reaction temperature, molar ratio of benzene to 1-octadecene and the amount of catalyst were lower, compared with the traditional reaction technologies. The experimental results demonstrated that the ionic liquid had higher activity at 30℃, with over 98% selectivity of monoalkylbenzene and 100% conversion of the olefin at the molar ratio 0.08 of FeCl3 in ionic liquid to 1-octadecene and 10 for benzene to 1-octadecene.展开更多
The alkylation of toluene with 1,3-pentadiene to produce pentyltoluene was carded out to obtain 2,6-dimethylnaphalene, which is an important intermediate during the production of 2,6-naphthalene dicarboxylic acid. Bas...The alkylation of toluene with 1,3-pentadiene to produce pentyltoluene was carded out to obtain 2,6-dimethylnaphalene, which is an important intermediate during the production of 2,6-naphthalene dicarboxylic acid. Based on our previous work using anhydrous AlCl3 as catalyst, [bupy]BF4-AlCl3 ionic liquids were employed to catalyze the reaction of 1,3-pentadiene with toluene. The experimental results show that [bupy]BF4-AlCl3 ionic liquids are suitable for the reaction especially when the molar ratio of AlCl3 to [bupy]BF4 is 1.75 : 1, and the reaction could proceed at the temperature as low as 0℃. It could be as active as pure AlCl3, but much more environmentally friendly.展开更多
The synthesis of 2, 4, 6-triisopropyl-1, 3, 5-trioxane with high yield and desirable selec- tivity from solvent-free cyclotrimerization of isobutyraldehyde catalyzed by ionic liquids was reported in this work.
Up to now the mechanism of Priedel-Crafts reactions catalyzed by ionic liquidhave not been fully understood, while carbocation mechanism was assumed. It was found that thesource of H^+ and the route of reaction initia...Up to now the mechanism of Priedel-Crafts reactions catalyzed by ionic liquidhave not been fully understood, while carbocation mechanism was assumed. It was found that thesource of H^+ and the route of reaction initiated the alkylation of benzene with ethylene catalyzedby [bmim]Cl/FeCl_3 ionic liquid. The fact that dewatered ionic liquids have catalytic activity forthe alkylation of benzene with ethylene suggests that there exists a new catalytic route. Thedistinctly Bronsted acid properties of 2-H in [bmim]Cl were found through FT-IR and HNMR analysis of[bmim]Cl after titration with water free KOH in alcohol solution. In addition, the chemical shiftsof proton on the [bmim]Cl ring, especially 2-H, are sensitive to the change of FeCl_3 content andshifted downfield when FeCl_3 was added into [bmim]Cl to form ionic liquid. Thus 2-H was easy to bedisengaged from imidazolium ring with formation of H^+ to initiate the reaction. Theisotope-substituted method was employed to prove this mechanism, through the GC-MS analysis ofalkylation products of deuterated benzene with ethylene. The route of alkylation catalyzed by FeCl_3ionic liquid was found to follow the carbocation mechanism, the resource of H^+ was presented andproved using HNMR analysis of ionic liquid to inspect the intensity change of 2-H. It was found thatthe intensity of 2-H reduced 23% after reaction showing that the H^+ arising from alkylationreaction was supplied by 2-H on the imidazole ring.展开更多
In this article,an efficient,simple and environmentally friendly approach to the synthesis of diacetals(diketals) pentaerythritol using SOH-functionalized ionic liquids(ILs) as catalysts was reported.The ILs show high...In this article,an efficient,simple and environmentally friendly approach to the synthesis of diacetals(diketals) pentaerythritol using SOH-functionalized ionic liquids(ILs) as catalysts was reported.The ILs show high catalytic activity and reusability with good to excellent yields of the desired products.Hammett method has been used to determine the acidity order of these ionic liquids and the results are consistent with the catalytic activities observed in acetalization reaction.Maximum product yield of 93%was observed on using[PSPy][OTf]as catalyst and it can be reused at least 8 times without obvious activity loss.展开更多
In this article, series of novel bi-SOaH-functionalized ILs were synthesized using simple, efficient and economic procedure. Hammer method had been used to determine the acidity order of these ionic liquids, and the a...In this article, series of novel bi-SOaH-functionalized ILs were synthesized using simple, efficient and economic procedure. Hammer method had been used to determine the acidity order of these ionic liquids, and the acidifies of bi-SOaH-functionalized ILs were stronger than that of traditional single-SOaH-functionalized ILs. Their catalytic activities in the synthesis of N-(3-phenyl)-3- oxo-1-(phenylpropyl)acetamide were investigated and they were consistent with their acidities.展开更多
Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-...Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis(pyranon-3-yl)methane hybrids with potential biological activities were constructed.展开更多
FeCl3-based ionic liquid [Bmim]Br/FeCl3 with lower viscosity was synthesized and its structure was character-ized with FT-IR spectroscopy. The denitrogenation performance of the ionic liquid was investigated using the...FeCl3-based ionic liquid [Bmim]Br/FeCl3 with lower viscosity was synthesized and its structure was character-ized with FT-IR spectroscopy. The denitrogenation performance of the ionic liquid was investigated using the Fushun shale diesel fraction with high nitrogen content. Experimental results showed that the ionic liquid presented good denitrogenation performance and the basic N and total N removal efficiency can reach 95.29% and 89.77% under conditions covering a tem-perature of 30 ℃, an IL/oil mass ratio of 1:1, an extraction time of 30 min, and a settling time of 2 h. Correspondingly, the basic N and total N contents in shale diesel fraction dropped from the original 5454 μg/g and 9832 μg/g to 257 μg/g and 1006 μg/g, respectively. In addition, the basic-N removal efficiency can still reach 60% at an IL/oil mass ratio of 1:7 during four recycles of the ionic liquid.展开更多
The phase diagram of InCl3-MBIC was constructed by DSC method. A clear, colorless and mobile ionic liquid was obtained and liquid down to 258 K. Both Raman scattering and ab initio calculations indicate that InCl4- ...The phase diagram of InCl3-MBIC was constructed by DSC method. A clear, colorless and mobile ionic liquid was obtained and liquid down to 258 K. Both Raman scattering and ab initio calculations indicate that InCl4- is the predominant anion.展开更多
A highly selective synthesis of 2,6-dimethylnaphthanlene(2,6-DMN) by transalkylation between 2-methylnaphthanlene(2-MN) and 1,2,4,5-tetramethylbenzene(TeMB) was performed with 1-alkyl-3-methylimidazo- lium alumi...A highly selective synthesis of 2,6-dimethylnaphthanlene(2,6-DMN) by transalkylation between 2-methylnaphthanlene(2-MN) and 1,2,4,5-tetramethylbenzene(TeMB) was performed with 1-alkyl-3-methylimidazo- lium aluminum chloride([Cnmim]Cl-AlCl3) ionic liquids(ILs) as catalysts. The influences of the alkyl group as the organic cation, the acidic strength of [C4mim]Cl-AlCl3 ILs as well as the reaction conditions on the catalytic performance were investigated. [C4mim]Cl-AlCl3 ILs[x(AlCl3)=71%] exhibited high activity and selectivity toward 2,6-DMN. The selectivity to 2,6-DMN and the 2,6-DMN/2,7-DMN ratio reached up to 68.2% and 3.7:1, respectively. The UV-Vis spectrum of TeMB treated by different ILs shows that the protonated degree of TeMB dependeds on the acidity strength of ILs, which has a significant impact on the reaction results. The high protonated degree of TeMB is advantageous to enhancing the conversion of transalkylation and the large stereo-hindrance effect of TeMB is favorable to improving the selecivity to 2,6-DMN.展开更多
The anodic behavior of neodymium in acidic AlCl3-1-ethyl-3-methyl-imidazolium chloride (AIC13-EMIC) ionic liquid was investigated by conducting linear sweep voltammeter and chonopotentiometry. The viscosity of Nd di...The anodic behavior of neodymium in acidic AlCl3-1-ethyl-3-methyl-imidazolium chloride (AIC13-EMIC) ionic liquid was investigated by conducting linear sweep voltammeter and chonopotentiometry. The viscosity of Nd dissolved ionic liquid and the surface morphologies of Nd were characterized using an Ostwald viscometer and a scanning electron microscope, respectively. The chemical composition of Nd surface was indentified by Raman spectra. The results showed that dissolution of Nd under anodic polarization occurred after the breakdown of oxide films. A viscous layer formed at the interface of Nd/ionic liquid during the galvanostatic process of 5 and 20 mA/cm^2. The formation of viscous layer was attributed to the accumulation of Nd dissolved AlCl3-EMIC ionic liquid, which had high viscosity. The oxide films could be removed thoroughly and the surface of Nd was homogeneous without etching pits, when viscous layer formed in the anodic process. Otherwise, the surface showed a pitting morphology.展开更多
The Hartree-Fock method has been employed to investigate the electronic structures of EMIM^+(1-ethyl-3-methyl-imidazolium^+), CuCl2^-, Cu2Cl3^-, CuCl3^2-, EMIM+^-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2- pa...The Hartree-Fock method has been employed to investigate the electronic structures of EMIM^+(1-ethyl-3-methyl-imidazolium^+), CuCl2^-, Cu2Cl3^-, CuCl3^2-, EMIM+^-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2- pairs. Full optimization and frequency analyses of EMIM^+, CuCl2^-, Cu2Cl3^-, CuC13^-, eight initial EMIM^+-CuCl2^-, six EMIM^+-Cu2Cl3^-, and four EMIM^+-CuCl3^2- geometries have been carried out using Gaussian-94 soft-package at 6-31+G(d,p) basis set level for hydrogen, carbon, nitrogen, chlorine atoms and Hay-Wadt effective core potential for copper atom. The electronic structures of lowest energy of EMIM^+-CuCl2^-, EMIM+-Cu2Cl3^-, EMIM^+-CuCl3^2-, single EMIM^+, CuCl2^-, Cu2Cl3^-, and CuCl3^2- have been comparatively studied. The calculated results showed that EMIM^+-CuCl2^- pair conformer of lowest energy was five ring parallel to Cl-Cu-Cl with 3.2A distance, EMIM^+-CuCl3^2- pair conformer of lowest energy was five ring parallel to CuCl3^2-plane with 3.4A distance, and the optimized EMIM^+-Cu2Cl3^- pair conformer of lowest energy was five ring perpendicular to Cl-Cu-Cl-Cu-Cl plane with 3.0A distance between the terminal Cl atoms and the 5-ring of EMIM^+. The cohesion between cations and anions is brought about by C-H. C1 hydrogen bonds that are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum because of no appearing of imaginary frequency. The assigned frequencies were in agreement with the experimental report. The low energy of interaction because of the bulkyasymmetry of EMIM+ and the charge dispersion of cation and anion leads to the low melting point of the ionic liquids, EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2-. The interaction energy of EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2- is 309.0 kJ/mol, 316.8 kJ/mol, and 320.2 kJ/mol, respectively. The relationship of interaction energy via distance between cations and anions was also investigated by single point energy scan.展开更多
Several 1-vinyl-3-alkylimidazolium halogens [VRIM]X, which are functional materials with ethylenic bonds, were synthesized using the microwave-assisted synthesis method. Fourier transform infrared spectroscopy and 1H ...Several 1-vinyl-3-alkylimidazolium halogens [VRIM]X, which are functional materials with ethylenic bonds, were synthesized using the microwave-assisted synthesis method. Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy were carded out to analyze the resultant structures. The electrochemical properties and solubility of [VRIM]Br were investigated and discussed in detail. The temperature dependence of pure [VRIM]Br over a wide temperature range of 298.15-323.15 K fitted the Arrhanius equation well. At certain low concentrations, the electrical conductivity of the [VRIM]Br solution significantly increased with increasing solution concentration. The electrical conductivities of the [VRIM]Br observed in water, methanol, and ethanol showed the trend σwater〉 σmethanol 〉σethanol Conductometry showed that the critical miceUe concentrations of the bromines in water, methanol, and ethanol were 6.8-6.9 × 10-6, 1.4-1.5 × 10-5, and 1.9-2.0×10-5 mol.L-1, respectively; these results indicate that [VRIM]Br is an excellent surfactant. The solubility of [VRIM]X in common solvents was determined at 293.15 K, and results indicated that a decrease in solubility could be observed with decreasing dielectric constant of the solvent, elongation of the alkyl chain of the cation, and increasing anion size. Solubility parameters were also determined according to the Hildebrand-Scoff equation.展开更多
bmim]Cl/FeCl3 ionic liquids (where bmim = 1-butyl-3-methylimidazolium) were characterized by XPS (X-ray photoelectron spectroscopy), FT-IR (Fourier transform infrared spectroscopy), Raman and NMR (nuclear magnetic r...bmim]Cl/FeCl3 ionic liquids (where bmim = 1-butyl-3-methylimidazolium) were characterized by XPS (X-ray photoelectron spectroscopy), FT-IR (Fourier transform infrared spectroscopy), Raman and NMR (nuclear magnetic resonance) spectra. The results show that Fe2Cl7 and FeCl4 ions are the principal anions in acidic ionic liquids, - - whose concentrations change with the content of FeCl3 and an equilibrium exists between them. An isosbestic point existing in FT-IR spectra indicates that an interaction involving at least two species occurs and their concentrations vary with acidity. Chemical shifts of the hydrogen located in the cations of ionic liquids are sensitive to the composition of ionic liquids. The change in chemical shifts may be explained in terms of anion-cation interactions. The chemical shifts of 2-H are affected by metal halides, which shift downfield and the 2-H is more deshielded with the increase in metal halides.展开更多
An efficient and environmental benign method is reported for the condensation of 3-methyl-1-phenyl-5-pyrazolone with carbonyl compounds in ionic liquids [Bmim]BF4 and [Bmim]PF6 catalyzed by ethylenediammonium diacetate.
This paper reports the ab initio and Density Functional Theory (DFT) studies on the structure of the ionic liquid 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM]+[PF6]-). Hartree-Fock (HF) and DFT(B3LYP) metho...This paper reports the ab initio and Density Functional Theory (DFT) studies on the structure of the ionic liquid 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM]+[PF6]-). Hartree-Fock (HF) and DFT(B3LYP) methods are respectively used to obtain the stable structure of the gas phase ion pair at the 6-311++G(d, p) basis set level. The theoretical IR spectra of [EMIM]+[PF6]- were obtained from the calculated vibrational frequencies and intensities. The changes of atomic charge population have been investigated using Natural Bond Orbital (NBO) analysis. The computational results show that there may exist hydrogen bonds between the cation and the anion. After ZPE and BSSE corrections, the interaction energy between the cation and the anion is –314.44 kJ?mol-1.展开更多
Using the ionic liquid(IL)1-octyl-3-methylimidazolium hexafluorophosphate as the extractant and methanol as the dispersion solvent,a dispersive liquid–liquid microextraction method was developed to extract silver n...Using the ionic liquid(IL)1-octyl-3-methylimidazolium hexafluorophosphate as the extractant and methanol as the dispersion solvent,a dispersive liquid–liquid microextraction method was developed to extract silver nanoparticles(AgN Ps)from environmental water samples.Parameters that influenced the extraction efficiency such as IL concentration,pH and extraction time were optimized.Under the optimized conditions,the highest extraction efficiency for AgN Ps was above 90% with an enrichment factor of 〉90.The extracted AgN Ps in the IL phase were identified by transmission electron microscopy and ultraviolet–visible spectroscopy,and quantified by inductively coupled plasma mass spectrometry after microwave digestion,with a detection limit of 0.01 μg/L.The spiked recovery of AgN Ps was 84.4% with a relative standard deviation(RSD)of 3.8%(n = 6)at a spiked level of 5 μg/L,and 89.7% with a RSD of 2.2%(n = 6)at a spiked level of 300 μg/L,respectively.Commonly existed environmental ions had a very limited influence on the extraction efficiency.The developed method was successfully applied to the analysis of Ag NPs in river water,lake water,and the influent and effluent of a wastewater treatment plant,with recoveries in the range of 71.0%–90.9% at spiking levels of 0.11–4.7 μg/L.展开更多
基金supports from National Natural Science Foundation of China(Nos.22172066,22378176)supported by State Key Laboratory of Heavy Oil Processing.Supported by Jiangsu Collaborative Innovation Center of TechnologyMaterial of Water Treatment,Suzhou University of Science and Technology.
文摘Development of clean desulfurization process that combines both efficient and environmentally friendly remains a significant challenge for diesel production.The photocatalytic oxidation desulfurization technology is regarded as a promising process depending on the superior electron transfer and visible light utilization of photocatalyst.Herein,the nonstoichiometry MoO_(3-x)with outstanding photoresponse ability is prepared and modified by imidazole-based ionic liquid[C_(12)mim]Cl to upgrade electronic structure.The interface H-bonding between MoO_(3-x)and[C_(12)mim]Cl regard as electronic transfer channel and the recombination of e^(-)-h^(+)pairs is effectively inhibited with the modification of[C_(12)mim]Cl.Deep desulfurization rate of 96.6%can be reached within 60 min and the MoO_(3-x)/[C_(12)mim]Cl(MoC_(12))photocatalyst demonstrated outstanding cyclic stability within 7 cycles in an extraction coupled photocatalytic oxidation desulfurization(ECPODS)system.The study provides a new perspective on enhancing photocatalytic desulfurization through defect engineering and surface modification.
基金financially supported by the National Key R&D Program of China(Grant No.2022YFE0207300)National Natural Science Foundation of China(Grant Nos.22179142 and 22075314)+1 种基金Jiangsu Funding Program for Excellent Postdoctoral Talent(Grant No.2024ZB051 and 2023ZB836)the technical support for Nano-X from Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences(SINANO).
文摘Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials of SPEs due to its remarkable compatibility with lithium metal anodes(LMAs)and suitability for in-situ polymerization.However,poor thermal stability,insufficient ionic conductivity and narrow electrochemical stability window(ESW)hinder its further application in lithium metal batteries(LMBs).To ameliorate these problems,we have successfully synthesized a polymerized-ionic-liquid(PIL)monomer named DIMTFSI by modifying DOL with imidazolium cation coupled with TFSI^(-)anion,which simultaneously inherits the lipophilicity of DOL,high ionic conductivity of imidazole,and excellent stability of PILs.Then the tridentate crosslinker trimethylolpropane tris[3-(2-methyl-1-aziridine)propionate](TTMAP)was introduced to regulate the excessive Li^(+)-O coordination and prepare a flame-retardant SPE(DT-SPE)with prominent thermal stability,wide ESW,high ionic conductivity and abundant Lit transference numbers(t_(Li+)).As a result,the LiFePO_(4)|DT-SPE|Li cell exhibits a high initial discharge specific capacity of 149.60 mAh g^(-1)at 0.2C and 30℃with a capacity retention rate of 98.68%after 500 cycles.This work provides new insights into the structural design of PIL-based electrolytes for long-cycling LMBs with high safety and stability.
基金Project supported by National Natural Science Foundation of China(21001017,21171160,21376031)the Lotus Scholars Program of Hunan+1 种基金the Natural Science Foundation of Hunan Province(13JJ3068)Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation(2014CL03,2014CL05)
文摘CeF3 and CeF3:Tb3+ nanocrystals were successfully synthesized by the ultrasound assisted ionic liquid (IL) method at room temperature. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), high-resolution transmission electron micrographs (HRTEM) and photoluminescence (PL) spectra were employed to characterize the nanocrystals. The results of XRD indicated that the obtained samples crystallized well with a hexagonal phase crystal structure. SEM and TEM images demonstrated that the obtained CeF3:Tb3+ nanocrystals had a discoid shapein the presence of ultrasound and IL, whereas only granular nanoparticles were obtained by magnetic stirring. The possible formation mechanisms of the crystal growth were proposed. The PL spectra of the CeF3:Tb3+ nanodisks exhibited a strong green emission when excited at 254 nm. Furthermore, the photoluminescence intensity of CeF3:Tb3+ of the discoid particles was largely improved com-pared with that of the granular nanoparticles.
基金Supported by the National Natural Science Foundation of China (No.20276038) and Beijing Natural Science Foundation (No.2052010).
文摘Abstract The study on the catalysis of ionic liquids for alkylation of benzene with 1-octadecene to synthesize LAB (linear alkylbenzenes) was performed. The results showed that the most important factor that governed the conversion of olefin and selectivity of LAB was reaction temperature. Moreover, the effects of different ionic liquids and molar ratio of benzene to 1-octadecene on the conversion and selectivity were obviously in different degrees. The reaction temperature, molar ratio of benzene to 1-octadecene and the amount of catalyst were lower, compared with the traditional reaction technologies. The experimental results demonstrated that the ionic liquid had higher activity at 30℃, with over 98% selectivity of monoalkylbenzene and 100% conversion of the olefin at the molar ratio 0.08 of FeCl3 in ionic liquid to 1-octadecene and 10 for benzene to 1-octadecene.
文摘The alkylation of toluene with 1,3-pentadiene to produce pentyltoluene was carded out to obtain 2,6-dimethylnaphalene, which is an important intermediate during the production of 2,6-naphthalene dicarboxylic acid. Based on our previous work using anhydrous AlCl3 as catalyst, [bupy]BF4-AlCl3 ionic liquids were employed to catalyze the reaction of 1,3-pentadiene with toluene. The experimental results show that [bupy]BF4-AlCl3 ionic liquids are suitable for the reaction especially when the molar ratio of AlCl3 to [bupy]BF4 is 1.75 : 1, and the reaction could proceed at the temperature as low as 0℃. It could be as active as pure AlCl3, but much more environmentally friendly.
基金We graleully appreciate the financial support from the National Natural Science Foundation of China(G2000048).
文摘The synthesis of 2, 4, 6-triisopropyl-1, 3, 5-trioxane with high yield and desirable selec- tivity from solvent-free cyclotrimerization of isobutyraldehyde catalyzed by ionic liquids was reported in this work.
文摘Up to now the mechanism of Priedel-Crafts reactions catalyzed by ionic liquidhave not been fully understood, while carbocation mechanism was assumed. It was found that thesource of H^+ and the route of reaction initiated the alkylation of benzene with ethylene catalyzedby [bmim]Cl/FeCl_3 ionic liquid. The fact that dewatered ionic liquids have catalytic activity forthe alkylation of benzene with ethylene suggests that there exists a new catalytic route. Thedistinctly Bronsted acid properties of 2-H in [bmim]Cl were found through FT-IR and HNMR analysis of[bmim]Cl after titration with water free KOH in alcohol solution. In addition, the chemical shiftsof proton on the [bmim]Cl ring, especially 2-H, are sensitive to the change of FeCl_3 content andshifted downfield when FeCl_3 was added into [bmim]Cl to form ionic liquid. Thus 2-H was easy to bedisengaged from imidazolium ring with formation of H^+ to initiate the reaction. Theisotope-substituted method was employed to prove this mechanism, through the GC-MS analysis ofalkylation products of deuterated benzene with ethylene. The route of alkylation catalyzed by FeCl_3ionic liquid was found to follow the carbocation mechanism, the resource of H^+ was presented andproved using HNMR analysis of ionic liquid to inspect the intensity change of 2-H. It was found thatthe intensity of 2-H reduced 23% after reaction showing that the H^+ arising from alkylationreaction was supplied by 2-H on the imidazole ring.
基金supported by National 863 High-Tech Research and Development Program of China(No. 2007AA05Z101)
文摘In this article,an efficient,simple and environmentally friendly approach to the synthesis of diacetals(diketals) pentaerythritol using SOH-functionalized ionic liquids(ILs) as catalysts was reported.The ILs show high catalytic activity and reusability with good to excellent yields of the desired products.Hammett method has been used to determine the acidity order of these ionic liquids and the results are consistent with the catalytic activities observed in acetalization reaction.Maximum product yield of 93%was observed on using[PSPy][OTf]as catalyst and it can be reused at least 8 times without obvious activity loss.
基金the National Natural Science Foundation ofChina(Nos.21003049,21073064)the Fundamental Research Funds for the Central Universities for financial support
文摘In this article, series of novel bi-SOaH-functionalized ILs were synthesized using simple, efficient and economic procedure. Hammer method had been used to determine the acidity order of these ionic liquids, and the acidifies of bi-SOaH-functionalized ILs were stronger than that of traditional single-SOaH-functionalized ILs. Their catalytic activities in the synthesis of N-(3-phenyl)-3- oxo-1-(phenylpropyl)acetamide were investigated and they were consistent with their acidities.
基金the National Natural Science Foundation of China(No.20772025)the Program for Science & Technology Innovation Talents in Universities of Henan Province(No.2008HASTIT006)the Natural Science Foundation of Department of Education of Henan Province(No.2008A150013).
文摘Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis(pyranon-3-yl)methane hybrids with potential biological activities were constructed.
基金financial support from the Doctoral Funds of Liaoning Provincial Natural Science Foundation (201601323)
文摘FeCl3-based ionic liquid [Bmim]Br/FeCl3 with lower viscosity was synthesized and its structure was character-ized with FT-IR spectroscopy. The denitrogenation performance of the ionic liquid was investigated using the Fushun shale diesel fraction with high nitrogen content. Experimental results showed that the ionic liquid presented good denitrogenation performance and the basic N and total N removal efficiency can reach 95.29% and 89.77% under conditions covering a tem-perature of 30 ℃, an IL/oil mass ratio of 1:1, an extraction time of 30 min, and a settling time of 2 h. Correspondingly, the basic N and total N contents in shale diesel fraction dropped from the original 5454 μg/g and 9832 μg/g to 257 μg/g and 1006 μg/g, respectively. In addition, the basic-N removal efficiency can still reach 60% at an IL/oil mass ratio of 1:7 during four recycles of the ionic liquid.
基金supportcd by NSFC(20041005).by NSF of Liaoning provincc(20011O2O35);by Education Burcau of Liaoning prox,incc.
文摘The phase diagram of InCl3-MBIC was constructed by DSC method. A clear, colorless and mobile ionic liquid was obtained and liquid down to 258 K. Both Raman scattering and ab initio calculations indicate that InCl4- is the predominant anion.
基金Supported by the National Natural Science Foundation of China(No.21076065)the Natural Science Foundation of Heilongjiang Province of China(No.ZD200820-02)the Science&Technology Research Foundation of Education Bureau of Heilongjiang Province,China(No.11531266)
文摘A highly selective synthesis of 2,6-dimethylnaphthanlene(2,6-DMN) by transalkylation between 2-methylnaphthanlene(2-MN) and 1,2,4,5-tetramethylbenzene(TeMB) was performed with 1-alkyl-3-methylimidazo- lium aluminum chloride([Cnmim]Cl-AlCl3) ionic liquids(ILs) as catalysts. The influences of the alkyl group as the organic cation, the acidic strength of [C4mim]Cl-AlCl3 ILs as well as the reaction conditions on the catalytic performance were investigated. [C4mim]Cl-AlCl3 ILs[x(AlCl3)=71%] exhibited high activity and selectivity toward 2,6-DMN. The selectivity to 2,6-DMN and the 2,6-DMN/2,7-DMN ratio reached up to 68.2% and 3.7:1, respectively. The UV-Vis spectrum of TeMB treated by different ILs shows that the protonated degree of TeMB dependeds on the acidity strength of ILs, which has a significant impact on the reaction results. The high protonated degree of TeMB is advantageous to enhancing the conversion of transalkylation and the large stereo-hindrance effect of TeMB is favorable to improving the selecivity to 2,6-DMN.
基金Project supported by the National Natural Science Foundation of China(51271166)
文摘The anodic behavior of neodymium in acidic AlCl3-1-ethyl-3-methyl-imidazolium chloride (AIC13-EMIC) ionic liquid was investigated by conducting linear sweep voltammeter and chonopotentiometry. The viscosity of Nd dissolved ionic liquid and the surface morphologies of Nd were characterized using an Ostwald viscometer and a scanning electron microscope, respectively. The chemical composition of Nd surface was indentified by Raman spectra. The results showed that dissolution of Nd under anodic polarization occurred after the breakdown of oxide films. A viscous layer formed at the interface of Nd/ionic liquid during the galvanostatic process of 5 and 20 mA/cm^2. The formation of viscous layer was attributed to the accumulation of Nd dissolved AlCl3-EMIC ionic liquid, which had high viscosity. The oxide films could be removed thoroughly and the surface of Nd was homogeneous without etching pits, when viscous layer formed in the anodic process. Otherwise, the surface showed a pitting morphology.
文摘The Hartree-Fock method has been employed to investigate the electronic structures of EMIM^+(1-ethyl-3-methyl-imidazolium^+), CuCl2^-, Cu2Cl3^-, CuCl3^2-, EMIM+^-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2- pairs. Full optimization and frequency analyses of EMIM^+, CuCl2^-, Cu2Cl3^-, CuC13^-, eight initial EMIM^+-CuCl2^-, six EMIM^+-Cu2Cl3^-, and four EMIM^+-CuCl3^2- geometries have been carried out using Gaussian-94 soft-package at 6-31+G(d,p) basis set level for hydrogen, carbon, nitrogen, chlorine atoms and Hay-Wadt effective core potential for copper atom. The electronic structures of lowest energy of EMIM^+-CuCl2^-, EMIM+-Cu2Cl3^-, EMIM^+-CuCl3^2-, single EMIM^+, CuCl2^-, Cu2Cl3^-, and CuCl3^2- have been comparatively studied. The calculated results showed that EMIM^+-CuCl2^- pair conformer of lowest energy was five ring parallel to Cl-Cu-Cl with 3.2A distance, EMIM^+-CuCl3^2- pair conformer of lowest energy was five ring parallel to CuCl3^2-plane with 3.4A distance, and the optimized EMIM^+-Cu2Cl3^- pair conformer of lowest energy was five ring perpendicular to Cl-Cu-Cl-Cu-Cl plane with 3.0A distance between the terminal Cl atoms and the 5-ring of EMIM^+. The cohesion between cations and anions is brought about by C-H. C1 hydrogen bonds that are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum because of no appearing of imaginary frequency. The assigned frequencies were in agreement with the experimental report. The low energy of interaction because of the bulkyasymmetry of EMIM+ and the charge dispersion of cation and anion leads to the low melting point of the ionic liquids, EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2-. The interaction energy of EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2- is 309.0 kJ/mol, 316.8 kJ/mol, and 320.2 kJ/mol, respectively. The relationship of interaction energy via distance between cations and anions was also investigated by single point energy scan.
基金Funded by the Special Funds of the National Natural Science Foundation of China(No.21174111)
文摘Several 1-vinyl-3-alkylimidazolium halogens [VRIM]X, which are functional materials with ethylenic bonds, were synthesized using the microwave-assisted synthesis method. Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy were carded out to analyze the resultant structures. The electrochemical properties and solubility of [VRIM]Br were investigated and discussed in detail. The temperature dependence of pure [VRIM]Br over a wide temperature range of 298.15-323.15 K fitted the Arrhanius equation well. At certain low concentrations, the electrical conductivity of the [VRIM]Br solution significantly increased with increasing solution concentration. The electrical conductivities of the [VRIM]Br observed in water, methanol, and ethanol showed the trend σwater〉 σmethanol 〉σethanol Conductometry showed that the critical miceUe concentrations of the bromines in water, methanol, and ethanol were 6.8-6.9 × 10-6, 1.4-1.5 × 10-5, and 1.9-2.0×10-5 mol.L-1, respectively; these results indicate that [VRIM]Br is an excellent surfactant. The solubility of [VRIM]X in common solvents was determined at 293.15 K, and results indicated that a decrease in solubility could be observed with decreasing dielectric constant of the solvent, elongation of the alkyl chain of the cation, and increasing anion size. Solubility parameters were also determined according to the Hildebrand-Scoff equation.
文摘bmim]Cl/FeCl3 ionic liquids (where bmim = 1-butyl-3-methylimidazolium) were characterized by XPS (X-ray photoelectron spectroscopy), FT-IR (Fourier transform infrared spectroscopy), Raman and NMR (nuclear magnetic resonance) spectra. The results show that Fe2Cl7 and FeCl4 ions are the principal anions in acidic ionic liquids, - - whose concentrations change with the content of FeCl3 and an equilibrium exists between them. An isosbestic point existing in FT-IR spectra indicates that an interaction involving at least two species occurs and their concentrations vary with acidity. Chemical shifts of the hydrogen located in the cations of ionic liquids are sensitive to the composition of ionic liquids. The change in chemical shifts may be explained in terms of anion-cation interactions. The chemical shifts of 2-H are affected by metal halides, which shift downfield and the 2-H is more deshielded with the increase in metal halides.
文摘An efficient and environmental benign method is reported for the condensation of 3-methyl-1-phenyl-5-pyrazolone with carbonyl compounds in ionic liquids [Bmim]BF4 and [Bmim]PF6 catalyzed by ethylenediammonium diacetate.
基金This work was supported by the National Natural Science Key Foundation of China (20490209) and Young Teacher Foundation of Beijing University of Chemical Technology (QN0308)
文摘This paper reports the ab initio and Density Functional Theory (DFT) studies on the structure of the ionic liquid 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM]+[PF6]-). Hartree-Fock (HF) and DFT(B3LYP) methods are respectively used to obtain the stable structure of the gas phase ion pair at the 6-311++G(d, p) basis set level. The theoretical IR spectra of [EMIM]+[PF6]- were obtained from the calculated vibrational frequencies and intensities. The changes of atomic charge population have been investigated using Natural Bond Orbital (NBO) analysis. The computational results show that there may exist hydrogen bonds between the cation and the anion. After ZPE and BSSE corrections, the interaction energy between the cation and the anion is –314.44 kJ?mol-1.
基金supported by the National Natural Science Foundation of China(No.21207124)Research Project of Beijing Municipal Education Commission(No.KM201110005009)the Special Fund for Quality Inspection Administration Public Welfare Scientific Research Funding(No.2012104001)
文摘Using the ionic liquid(IL)1-octyl-3-methylimidazolium hexafluorophosphate as the extractant and methanol as the dispersion solvent,a dispersive liquid–liquid microextraction method was developed to extract silver nanoparticles(AgN Ps)from environmental water samples.Parameters that influenced the extraction efficiency such as IL concentration,pH and extraction time were optimized.Under the optimized conditions,the highest extraction efficiency for AgN Ps was above 90% with an enrichment factor of 〉90.The extracted AgN Ps in the IL phase were identified by transmission electron microscopy and ultraviolet–visible spectroscopy,and quantified by inductively coupled plasma mass spectrometry after microwave digestion,with a detection limit of 0.01 μg/L.The spiked recovery of AgN Ps was 84.4% with a relative standard deviation(RSD)of 3.8%(n = 6)at a spiked level of 5 μg/L,and 89.7% with a RSD of 2.2%(n = 6)at a spiked level of 300 μg/L,respectively.Commonly existed environmental ions had a very limited influence on the extraction efficiency.The developed method was successfully applied to the analysis of Ag NPs in river water,lake water,and the influent and effluent of a wastewater treatment plant,with recoveries in the range of 71.0%–90.9% at spiking levels of 0.11–4.7 μg/L.