SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2012
·
IF 2.098
Yunchang Fan,Sheli Zhang,Qiang Wang,Junhai Li,Haotian Fan,Dongkai Shan
The interaction of an amino-functionalized ionic liquid, 1-(2-aminoethyl)-3-butylimidazolium bromide ([NH 2 C 2 C 4 im]Br) with two enzymes, pepsin and papain was investigated using fluorescence spectroscopic technique. It is found that [NH 2 C 2 C 4 im]Br has strong ability to quench the intrinsic fluorescence of pepsin and papain. Quenching mechanisms are considered as static quenching for papain and dynamic quenching for pepsin, respectively. The binding constants and the number of binding sites ( n ) of [NH 2 C 2 C 4 im]Br to papain were calculated at different temperatures. The thermodynamic parameters such as free energy change (Δ G ), enthalpy change (Δ H ) and entropy change (Δ S ), were calculated by thermodynamic equations. The values of Δ G , Δ H and Δ S suggest that interaction of [NH 2 C 2 C 4 im]Br with the two enzymes is spontaneous. Hydrogen bonding and van der Waals interactions play important roles in the binding process of [NH 2 C 2 C 4 im]Br to papain. However, hydrophobic interaction is the main driving force for the interaction of [NH 2 C 2 C 4 im]Br with pepsin. The results of three-dimensional fluorescence spectra show that [NH 2 C 2 C 4 im]Br has no obvious effects on the polypeptide structures of the two enzymes. Additionally, the [NH 2 C 2 C 4 im]Br-containing system can slightly increase the activities of the two enzymes.
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2020
·
IF 2.463
Lifang Hu,Hong Peng,Qi Xia,Yu Zhang,Roger Ruan,Wenguang Zhou
Ionic liquid (IL) pretreatment of lignocellulosic biomass has been the focus of attention due to its numerous advantages compared with conventional methods. The change in the physicochemical properties of the three main components of this biomass during IL pretreatment is the key factor for their further utilization and conversion. In this study, hemicellulose extracted from bamboo was dissolved in three ILs with different imidazolium cations and the same anion of acetate, including 1-ethyl-3-methylimidazolium acetate (EmimAc), 1-butyl-3-methylimidazolium acetate (BmimAc), and 1-allyl-3-methylimidazolium acetate (AmimAc). The solubility of hemicellulose in the ILs was measured as a function of temperature from 120 °C to 150 °C. Hemicelluloses regenerated from the saturated IL solutions were characterized by using Fourier transform infrared spectroscopy , gel permeation chromatography , gas chromatography–mass spectrometry, 13C–1H heteronuclear single-quantum correlation nuclear magnetic resonance, and thermogravimetry . The solubility of hemicellulose in the three ILs was greatly affected by temperature, and the solubility increased with increasing temperature. The highest solubilities per 100 g of IL were 15.56, 15.09, and 6.73 g in BmimAc, EmimAc, and AmimAc, respectively. Hemicelluloses regenerated from saturated IL solutions showed similar physicochemical features with that of the original hemicellulose before being pretreated with ILs. These features included molecular weight , relative neutral sugar composition , structural feature, and thermal stability . Hence, hemicellulose was litter degraded during IL solving. In addition, the recovered EmimAc was analyzed after dissolving hemicellulose to a saturated state at 150 °C by using 13C and 1H NMR. The recovered IL contained minimal amounts of ethanol and other impurities.
✓ 已验证
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2022
·
IF 7.305
Guoqiang Xing,Guoqiang Kuang,Yijie Tao,Yi Wang,Yue Kang,Yafei Guo,Shiguo Zhang
Polymer electrolytes are the key composite for all-solid electrochromic devices due to their unique properties including high ionic conductivity , good flexibility, etc. However, such applications are still impeded by the poor mechanical strength . In this study, novel quasi-solid polymer/ionic liquid composite electrolyte is constructed and the tensile strength is greatly enhanced by coupling epoxy composite with glass fibers (GFs) as the reinforcement. The tensile strength of the composite electrolyte is tripled and reaches 7.6 MPa after optimizing the content of GFs with the ionic conductivity of 1.75 × 10 −5 S cm −1 . Then, a dual-coloring electrochromic device fabricated with the composite electrolyte presents excellent switching stability (18000 cycles, >180000 s), fast response (˂2 s), ultra-high coloring efficiency (η = 451 cm 2 /C) and low driving voltage (±1 V). In addition, a substrate-free and flexible electrochromic device based on the composite electrolyte is successfully assembled, which demonstrates remarkable electrochromic behaviors, unique flexibility and mechanical stability. This work may promote the development of low-cost, easily-assembled, ultrahigh-flexible and high-performance electrochromic devices.
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Chunli Xu,Bin Liu,Wenjun Ning,Xuyun Wang
A simple, convenient and highly sensitive sensor for ascorbic acid (AA) detection is presented. The sensor was prepared based on graphene oxide (GO) and ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF 6 ) nanocomposites. Scanning electron microscopy and Fourier transform infrared spectroscopy were used to study the morphology and functionalization of the sensing materials. The electrochemical detection of ascorbic acid was studied by differential pulse voltammetry, utilising a GO-IL modified glassy carbon electrode (GCE) in a linear response range from 0.01 mM to 4.0 mM, which exhibited a relatively low detection limit of 3.33 μM ( S / N = 3). In addition, the GO-IL nanocomposite exhibited appreciable stability, reproducibility and selectivity. The electrochemical sensor can be used for the determination of ascorbic acid in actual drugs.
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2020
·Vol. 49
·期 3
·257-271
·
IF 1.273
Zhu Xiao,Song Mengling,Ling Baoping,Wang Sihan,Luo Xiaoyan
Abstract A novel anion-functionalized protic ionic liquid (IL), [DBUH][Triz], has been synthesized from 1,8-diazabicyclo [5.4.0]undec-7-ene (DBU) and 1,2,4-triazole (Triz). Density ( ρ ) and viscosity ( η ) of [DBUH][Triz] at different temperatures have been measured and the influence of temperature has been analyzed quantitatively. Then, the applications of [DBUH][Triz] in CO 2 absorption have been investigated. It has been detected that this ionic liquid, which was easily prepared, shows excellent reversibility and a high absorption capacity, about 1.5 mol CO 2 per 1 mol of IL (about 0.3 g CO 2 per 1 g of IL). In addition, the influence of temperature, pressure and moisture on the absorption performance of [DBUH][Triz] has been studied separately, indicating that absorption is promoted by lower temperature and higher CO 2 pressure. In addition, the mechanism of chemical absorption at two active sites has been deduced based on quantum-chemical calculations and 13 C NMR spectra coupled with IR spectra. Furthermore, the equilibrium constant of chemical absorption ( K ) was calculated from the CO 2 capacity at different temperatures ( T ) and a good linear relationship between the natural logarithm of the equilibrium constant ln K and 1/ T was obtained with R 2 of 0.996. From the slope and intercept of the fitted straight line, the molar reaction enthalpy change (Δ r H m ) and molar reaction entropy change (Δ r S m ) were analyzed, indicating that the capture of CO 2 is an exothermic process and the IL–CO 2 complex is less ordered than the pure ionic liquid. Graphic Abstract
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2015
·
IF 2.858
Guowei Wang,Jiarong Guo,Linghua Zhuang,Yan Wang,Bin Xu
Gemini imidazolium ionic liquid , 3,3′-[1,2-ethanediylbis (oxy-2,1-ethanediyl)]-bis[1-methyl-imidazolium]-dibromide ([C 6 O 2 (mim) 2 ][Br] 2 ), was used for the dissolution and regeneration of white hide powder (from pigskin), and blend white hide powder with cellulose for the easy production of white hide powder/cellulose composite. Dissolution performance of white hide powder in [C 6 O 2 (mim) 2 ][Br] 2 was studied. The native white hide powder and [C 6 O 2 (mim) 2 ][Br] 2 regenerated white hide powder were characterized by FT-IR, XRD, DSC–TG and FE-SEM. The results showed that [C 6 O 2 (mim) 2 ][Br] 2 was a good solvent to white hide powder. The dissolution time was 55 min when the white hide powder was 8% at 120 °C. The dissolution time of [C 6 O 2 (mim) 2 ][Br] 2 for white hide powder was shorter than those of common ionic liquids. The triple helical structure of white hide powder was partly destroyed during [C 6 O 2 (mim) 2 ][Br] 2 dissolution. The possible mechanism of white hide powder dissolution in [C 6 O 2 (mim) 2 ][Br] 2 and the regeneration of white hide powder in methanol had been proposed. White hide powder/cellulose composites were successfully dissolved in [C 6 O 2 (mim) 2 ][Br] 2 . The performance of white hide powder/cellulose film was measured by FT-IR and TG. The tensile strength , and elongation at break of white hide powder/cellulose composite films were tested. This work demonstrated that the white hide powder/cellulose composite exhibited some potential in collagen-based tissue engineering.
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2014
·
IF 4.058
Wei Jiang,Wenshuai Zhu,Yonghui Chang,Yanhong Chao,Sheng Yin,Hui Liu,Fengxia Zhu,Huaming Li
A new family of dialkylpiperidinium tetrachloroferrate catalysts, such as [C 2 OHmpip]FeCl 4 , [C 4 mpip]FeCl 4 , [C 8 mpip]FeCl 4 , and [C 12 mpip]FeCl 4 , were synthesized and characterized by FT-IR, Raman, and ESI-MS. Their catalytic activities for oxidation of dibenzothiophene (DBT) in extraction and catalytic oxidative desulfurization system (ECODS) were evaluated using different ionic liquids. Results indicated that the 97.1% removal of DBT was obtained with [C 4 mpip]FeCl 4 as catalyst in ionic liquid [C 8 mim]BF 4 at 30 °C in 60 min. The optimal H 2 O 2 /sulfur molar ratio was only 3.5:1, which suggested that the catalyst was one of the most efficient catalysts reported so far. UV–Vis spectra provided an evidence that the lower desulfurization reactivity in PF 6 − -containing ionic liquids was attributed to the strong interaction between ionic liquid and DBT. Through the gas chromatography–mass spectrometer (GC–MS) analysis, dibenzothiophene sulfone was proved to be the only product of oxidation of DBT. Furthermore, the process of ECODS system was confirmed by GC–MS.
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 36
·13822-13829
·
IF 8.262
Xiaowei Li,Sijian Li,Zhengxi Zhang,Jun Huang,Li Yang,Shin-ichi Hirano
In this work, a new class of high-performance polymeric ionic liquid–silica hybrid ionogel electrolytes (HIGEs) is developed by a nonaqueous sol–gel route, in which LiTFSI–ionic liquid as the ion conducting phase is immobilized with a hybrid pyrrolidinium-based polymeric ionic liquid and silica matrix. The thermal and electrochemical properties of these HIGEs as well as their application in lithium metal batteries (LMBs) are investigated. It is found that HIGEs reveal excellent thermal stability, good room temperature ionic conductivity, high electrochemical stability, a suitable lithium ion transference number, and potential to suppress Li dendrite formation. In particular, Li/LiFePO4 cells with the as-obtained HIGE at 0.2C rate can deliver a discharge capacity of about 150 mA h g−1 at 25 °C, with excellent capacity retention. Moreover, at 0.5C, 1.0C, and 2.0C, the stable discharge capacities are as high as 138.1 mA h g−1, 120.3 mA h g−1 and 73.8 mA h g−1, respectively. The desirable battery performance can be attributed to the good electrochemical properties of HIGEs and interfacial compatibility between HIGEs and electrodes. These findings show that HIGEs prepared in this work have great potential for application as safe electrolytes in LMBs.
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2021
·
IF 5.03
Tianlin Wang,Xu Gong,Chuanchao Shen,Guangren Yu,Xiaochun Chen
The accumulation of waste PET leads to serious environmental problem. PET degradation has been hot topic and is studied by lots of researchers. At present, numerous catalysts have been developed, among which ionic liquid catalyst is attractive due to its excellent advantages like convenient recycling and highly catalytic effect. In this work, a series of ionic liquids based on 1,1,3,3-tetramethylguanidine (TMG) were synthesized and used as catalyst of PET degradation. The influence of different structure of cation and different metal salt on PET degradation were studied. DFT calculation showed that the interaction between the ionic liquid and ethylene glycol can be changed by adjustment of the structure of the cation. At optimal condition, using [C 6 TMG]Cl/2ZnCl 2 as catalyst, PET conversion was 100% and BHET yield was 92.7%. To our best knowledge, this is first report about ionic liquid catalyst of PET degradation with superior BHET yield. Catalytic effect of [C 6 TMG]Cl/2ZnCl 2 did not obviously decrease after it was reused for six times. Moreover, the degradation of commercial beverage bottles was investigated using [C 6 TMG]Cl/2ZnCl 2 as the catalyst, the BHET yield of 84% was obtained, and the quality purity of the product was 90%. In addition, possible mechanism was explored.
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2021
·
IF 6.165
Fulin Li,Cheng Peng,Ke Yuan,Qiwei Xu,Hang Song
Terpinen-4-ol in natural Tea tree oil (TTO) plays an important role in physiological activities. Selectively removing of 1,8-cineole and the monoterpenes such as γ-terpinene from TTO is necessary for TTO comfort and safety. In this study, the density functional theory (DFT) was employed to estimate the interaction energies between ILs and terpinen-4-ol for preliminarily screening ionic liquid type of extraction agents. It was found hexalkylguanidinium ionic liquids (ILs) [diBTMG]Br exhibited good extraction distribution coefficient of terpinen-4-ol (2.54) and higher extraction selectivity of terpinen-4-ol (6.9 to 1,8-cineole and 9 to γ-terpinene, respectively). The single extraction yield of terpinen-4-ol by the IL could reach to 90%. After the extraction, subsequent twice extractions with n-hexane and water can realize satisfactorily recovery and reuse of all extraction agents. The deterpenation of TTO has advantages of lower energy consumption, safety, environmentally friendly and less cost. It would provide an alternative strategy for the practical deterpenation production of essential oil with ionic liquids.
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Xiaocong Yan,Fangfang Zhang,Haining Zhang,Haolin Tang,Mu Pan,Pengfei Fang
Improving catalytic performance of the oxygen reduction reaction (ORR) of Pt/C catalysts is essential for reducing Pt-loading and the according cost of proton exchange membrane fuel cells (PEMFCs). Herein, we report a new conceptual design of catalyst layers to improve the ORR performance of Pt/C catalysts by replacing perfluorosulfonated ionomers with protic poly(ionic liquid) as a proton conductor. The specific activity of the designed catalyst at 0.9 V under acidic conditions is over three times higher than that of catalyst using Nafion as the proton conductor. Furthermore, the durability test reveals that the introduction of protic poly(ionic liquid) ionomers can protect Pt nanoparticles against aggregation during potential cycles, but it is less durable than Nafion because of the nature of hydrocarbons. Nevertheless, we believe that replacing perfluorosulfonated ionomers with protic poly(ionic liquid) as proton conductors could be a promising strategy to design an efficient cathode for low Pt-loading PEMFCs.
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Hongbing Song,Yongjie Wang,Yule Liu,Lei Chen,Bingxiao Feng,Xin Jin,Yu Zhou,Tingting Huang,Meng Xiao,Fangmin Huang,Hengjun Gai
Three ionic liquid (IL) monomers consisting of one, two, and four benzene rings were designed with 2-phenylimidazole and polymerized with α,α′-dichloro-p-xylene (DCX) and formaldehyde dimethyl acetal (FDA) to form a series of novel poly(ionic liquid)s (PILs). In this process, the designed ILs were employed as active ionic sites, and DCX and FDA were selected as cross-linkers. Self-condensation of the cross-linker provided a large specific surface area for the hypercross-linked organic framework, while co-condensation between the cross-linker and IL introduced active sites to the framework. The obtained porous hypercross-linked PILs not only promoted CO2 capture and the selective absorption of CO2/N2 but also showed good activity for the cycloaddition of epoxide with CO2. HP-[BZPhIm]Cl-DCX-1 with a large surface area (763 m2·g–1) showed a CO2 uptake capacity of 1.47 mmol·g–1 and offered a 98.9% yield of the CO2 cycloaddition product with epichlorohydrin at 80 °C for 24 h under 0.1 MPa CO2 pressure. The designed PILs provide an important reaction for CO2 utilization.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）