CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Lu Qi,Xianghai Meng,Rui Zhang,Haiyan Liu,Chunming Xu,Zhichang Liu,Peter A.A. Klusener
Droplet size distribution (DSD) and mean droplet size of chloroaluminate ionic liquid (IL)–heptane dispersion in a stirred vessel were investigated as a model system for the composite ionic liquid/hydrocarbon system applied in the commercial isobutane alkylation process. Focused beam reflectance measurement was used to identify the phase inversion, and particle video microscope (PVM) was employed to measure the DSD of IL-continuous dispersions. The effects of agitation speed and dispersed phase holdup on the DSD and mean droplet size were investigated. Phase inversion was found at a heptane hold-up of just above 0.5. The observed DSDs could be described well by logarithmic normal distributions in spite of variable operating conditions. The DSDs appeared to be more or less independent of the dispersed phase holdup ( ϕ heptane ⩾ 0.3) at the same agitation speed. A semi-empirical correlation based on Shinnar theory was proposed to predict the droplet mean size in the impeller region for the IL-continuous dispersion, and the predicted value agreed well with the experimental data. This work will be a good basis to predict the dispersion behavior under process conditions.
研究领域:
化学工程
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流体力学
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多相系统
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过程工程
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胶体与界面科学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2022
·
IF 13.599
Xi Wang,Yong Wang,Yiyu Wu,Yunmiao Fan,Yang Tian
Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) solid garnet-type electrolyte has been widely reported due to its outstanding safety and electrochemical stability. However, the inherent rigidity and brittleness of LLZTO lead to poor contact with anode/cathode and the operation failure of full cells. Herein, the dual-interlayers are constructed as the fast interfacial ion-migration channel by using Ti 3 C 2 T x (MXene, T x is –O, –OH, –F) with trace ionic liquid (IL), which promote the intimate contact between LLZTO and anode/cathode and suppress Li-dendrites growth. Notably, IL can wet the cathode to promote intimate interface contact and be decomposed into some inorganic compounds (such as Li 3 N, LiF, and Li 2 S x ), resulting in reduced interfacial resistance and fast Li-ion transportation. Consequently, in the prepared Li-symmetric cell, the interfacial resistance on the anode side plunges to 33.1 Ω cm −2 , and stably maintains over 1000 h without short circuit at 0.05 mA cm −2 . The full cell of Li|LiFePO 4 delivers a high initial capacity of 158.52 mA h g −1 and outstanding retention of 90.18% after 100 cycles at 60 °C and 0.2 C. Our work provides an efficient strategy to design dual-interlayers between LLZTO and anode/cathode for the interfacial modification to enhance the performance of solid garnet batteries.
研究领域:
材料科学
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电化学
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固态电池
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界面工程
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能源材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2017
·
IF 6.395
Yongpeng Cui,Huanlei Wang,Nan Mao,Wenhua Yu,Jing Shi,Minghua Huang,Wei Liu,Shougang Chen,Xin Wang
The increasing demand for supercapacitors with high energy and power density has attracted extensive attention in designing advanced carbon materials with high accessible surface area, hierarchical porosity , and 2D/3D morphology. Here, we report a new approach to tune the morphology and structure of the nanocarbons by using methyl cellulose as the precursor. Due to the varying effect of different activating agents, the interconnected sheet-like carbon with a high surface area of up to 2285 m 2 g −1 and a thickness down to ∼4 nm can be obtained. These important characteristics make the nanocarbons demonstrate a high capacitance of 144 F g −1 at 1 A g −1 and 20 °C, and an excellent capacitance retention ratio of 64% at 100 A g −1 in ionic liquid . Because of the high fraction of meso/macropores for nanocarbons, an outstanding capacitance of 116 F g −1 can be achieved at 0 °C, with a high capacitance retention ratio of 39% at 100 A g −1 . A high energy of 16–17 and 9–10 W h kg −1 can be maintained at 20 and 0 °C when the supercapacitor is charged in less than 1s. The excellent electrochemical response of nanocarbons suggests that the proposed preparation process is promising for developing advanced carbon electrodes.
研究领域:
材料科学
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电化学
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纳米科技
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能源存储
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功能材料
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Libo Deng,Wenhua Zhong,Jubei Wang,Peixin Zhang,Haoming Fang,Lei Yao,Xuqing Liu,Xiangzhong Ren,Yongliang Li
Biomass-derived carbons have been extensively researched as electrode material for energy storage and conversion recently. However, most of the previous works convert crude biomass directly into carbon and the electrochemical capacitances for the resultant carbons are quite often underestimated as well as large variations in capacitances exist in literatures due to the complex nature of biomass, which practically hinder their applications. In this work, polysaccharide nanofibers were extracted from an inexpensive natural fungus using a hydrothermal method and were converted to porous carbon nanofibers (CNFs) by potassium hydroxide activation. The porous carbons were assembled into symmetric supercapacitors using both potassium hydroxide and an ionic liquid (IL) as electrolytes. Solid state nuclear magnetic resonance characterization showed that the micropores of the as-prepared carbons are accessible to the IL electrolyte when uncharged and thus high capacitance is expected. It is found in both electrolytes the electrochemical capacitances of CNFs are significantly higher than those of the porous carbon derived directly from the crude fungus. Furthermore, the CNFs delivered an extraordinary energy density of 92.3 Wh kg −1 in the IL electrolyte, making it a promising candidate for electrode materials for supercapacitors.
研究领域:
材料科学
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能源化学
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纳米技术
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电化学
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可再生能源
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2011
·Vol. 102
·期 11
·6469-6472
·
IF 4.365
Feng Guo,Zhen Fang,Xiao-Fei Tian,Yun-Duo Long,Li-Qun Jiang
Catalytic conversion of un-pretreated Jatropha oil with high-acid value (13.8 mg KOH/g) to biodiesel was studied in ionic liquids (ILs) with metal chlorides. Several commercial ILs were used to catalyze the esterification of oleic acid . It was found that 1-butyl-3-methylimidazolium tosylate ([BMIm][CH 3 SO 3 ]; a Brønsted acidic IL) had the highest catalytic activity with 93% esterification rate for oleic acid at 140 °C but only 12% biodiesel yield at 120 °C. When FeCl 3 was added to [BMIm][CH 3 SO 3 ], a maximum biodiesel yield of 99.7% was achieved at 120 °C. Because metal ions in ILs supplied Lewis acidic sites, and more of the sites could be provided by trivalent metallic ions than those of bivalent ones. It was also found that the catalytic activity with bivalent metallic ions increased with atomic radius. Mixture of [BMIm][CH 3 SO 3 ] and FeCl 3 was easily separated from products for reuse to avoid producing pollutants.
研究领域:
能源化学
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绿色化学
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催化化学
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生物燃料
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有机化学
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环境友好过程
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可再生能源
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2013
·
IF 3.777
Heng Zhang,Yi Lu,Chang-Dong Gu,Jian-Bin Cai,Xiu-Li Wang,Jiang-Ping Tu
Amorphous Ni–P–C films are fabricated by combining the electrodeposition of Ni–P films from a eutectic-based ionic liquid and the direct current magnetron sputtering of amorphous carbon top-layer. The carbon top-layer with a thickness of about 10 nm is homogeneously coated on the surface of the Ni–P films. A comparison study is undertaken between Ni–P and Ni–P–C films to evaluate the microstructure and the electrochemical performances of the composite films as anode materials for lithium ion batteries , which allow the decoupling of the effect of the carbon layer . It is found that at lower discharge–charge current densities, the cyclability of both Ni–P and Ni–P–C films is similar. As the discharge–charge current density increases, the Ni–P–C film exhibits improved capability and reversibility over the Ni–P film. The Ni–P–C film delivers an initial discharge capacity of 1060 mAh g −1 at 250 mA g −1 and the capacity retention after 50 cycles is 62%, much higher than that of the Ni–P film (51%). The cyclability of Ni–P–C film at different discharge–charge current densities from 200 to 500 mA g −1 is also much better than those of Ni–P film. This study indicates that the introduction of a carbon top-layer on Ni–P film could significantly improve the electrochemical performances due to the decreased interface electric resistance and the structure stability.
研究领域:
材料科学
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电化学
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纳米材料
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能源存储
·
薄膜技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2024
·
IF 3.7
Xiangyi Kong,Jie Cheng,Wei Meng,Shujing Han,Zhen Song,Zhiwen Qi
As a volatile organic compound (VOC), styrene can pose significant risks to human health and environment if released into the air without proper treatment. Absorption based on ionic liquids (ILs) has been widely regarded as a promising VOC treatment approach, whereas there is limited research on capturing styrene by ILs. In this work, a multilevel framework was proposed to screen IL absorbents from the largest number of cation-anion combinations in the latest COSMObase. The COSMO-RS model is applied to estimate the absorption and desorption potentials of all IL candidates for styrene capture based on solubility prediction, while important physical properties of them namely melting point, viscosity, and toxicity are estimated by a recently-reported deep learning model. A parallel screening specific to the commercially available ILs in the initial candidate database was also performed. The top-ranked three ILs, identified in both scenarios with and without limiting the commercially availability, were further evaluated in a simulated absorption-desorption process in Aspen Plus. The most promising ILs in each scenario were figured out, which vividly demonstrates the value of discovering novel ILs.
研究领域:
环境化学
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化学工程
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绿色溶剂
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计算化学
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大气污染控制
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2011
·
IF 2.794
Yuanchao Pei,Jing Liu,Zhenning Yan,Zhiyong Li,Jing Fan,Jianji Wang
In this paper, the interactions between cationic dyes and the ionic liquids (ILs) have been studied by 31 P nuclear magnetic resonance (NMR), UV–Vis spectroscopy and conductometric measurements at different temperatures. It was shown that a decrease in the measured specific conductance of the (dye + IL) mixtures was caused by the formation of non-conducting or less conducting (dye + IL) associates. The associates were formed by 1:1 ratio of cation of the cationic dyes and anion of the ILs by using the 31 P NMR and UV–Vis spectroscopy methods. The association constants were calculated by theoretical model based on the deviation from linear behavior, and the association constants were as high as 10 6 (L · mol −1 ) 2 . Thermodynamic results imply that the formation process of association was exothermic nature. It is expected that the associates reported here would have promising application as active materials for the preparation of ion-selective electrode used in the determination of ILs concentrations.
研究领域:
物理化学
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分析化学
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胶体与界面化学
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药物化学
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分子生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2019
·
IF 2.29
Xuzhao Yang,Jun Wang,Yun Fang
Experimental s olubility of D-(+)-glucose and D-(−)-fructose in three asymmetrical dicationic ionic liquids (DILs), 1-(3-(trimethylammonio)prop-1-yl)-3-methylimidazolium bis(dicyanamide) ([MIMC 3 N 111 ][N(CN) 2 ] 2 ), 1-(3-(trimethylammonio)prop-1-yl)-1-methylpiperidinium bis(dicyanamide) ([MPiC 3 N 111 ][N(CN) 2 ] 2 ) and 1-(3-(trimethylammonio)prop-1-yl)pyridinium bis(dicyanamide) ([PyC 3 N 111 ][N(CN) 2 ] 2 ), was determined through an isothermal technique from 323.15 K to 353.15 K at 0.1 MPa. The solubility of the two sugars in selected DILs increased with elevating temperature and the solubility decreased in the following order: D-(−)-fructose > D-(+)-glucose. The Apelblat, λh , NRTL, Wilson and UINQUAC models were respectively employed to correlate the experimental solubility values with temperature. The thermodynamics of dissolution of D-(+)-glucose and D-(−)-fructose in the studied DILs, enthalpy of dissolution (Δ diss 0 H ), Gibbs energy of dissolution (Δ diss 0 G ) and entropy of dissolution (Δ diss 0 S ), were also evaluated based on the experimental solubility data. The results indicated that enthalpic contributions were dominant in the dissolution process of D-(+)-glucose and D-(−)-fructose in those DILs.
研究领域:
物理化学
·
溶液化学
·
热力学
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绿色溶剂
·
碳水化合物化学
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2017
·
IF 4.95
Datong Wu,Qiuhong Yin,Pengfei Cai,Xiaoyong Zhao,Yuanjiang Pan
Novel task-specific ionic liquids derived from (S)-phenyl amino acid were prepared as a chiral sensor for the first time. It was found that the ionic liquids exhibited different chiral visual responses to the enantiomers . When (S)-tryptophan was treated with the sensor and Cu(II) in water, the clear solution would change to a sapphire suspension. Differently, another enantiomer could not produce the precipitate. Furthermore, the enantiomers could generate different colors in DMSO under the same conditions. The substantial difference contributes to the easy discrimination with visual determination. Four racemates were successfully tested with this strategy. The precipitation was isolated in the range of 90–94% yields after complete formation of the coordinative bonds, which could be as a simple way for enantioseparation. The responsive mechanism of the sensor was studied by NMR spectroscopy , FTIR and SEM . UV-vis spectrophotometer was used to monitor the colorimetric signal of the racemate with different e.e. values.
研究领域:
分析化学
·
有机化学
·
超分子化学
·
药物化学
·
化学生物学
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材料科学
·
分子识别
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Xin Zheng,Fang Huang,Lihui Chen,Liulian Huang,Shilin Cao,Xiaojuan Ma
Three ionic liquids (ILs) with increasing dissolution power, 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]), 1-allyl-3-methylimidazolium chloride ([Amim][Cl]), and 1-ethyl-3-methylimidazolium acetate ([Emim][Ac]), were selected for cellulose dissolution and film preparation through regeneration. The physical properties of the films were investigated, and the correlation between the IL used and the film properties was evaluated. The results indicated that the superior cellulose dissolution system, [Emim][Ac], had the most difficult regeneration process (i.e., more time was required for gel formation), followed by [Amim][Cl], and [Bmim][Cl]. On the other hand, the film produced from [Amim][Cl] had the highest crystallinity, transparency, and tensile strength, followed by the films produced from [Bmim][Cl] and [Emim][Ac]. It was inferred that stronger and more ordered molecular arrangements and inter-molecular interactions preferentially occurred during cellulose regeneration from [Amim][Cl] than during cellulose regeneration from [Bmim][Cl] and [Emim][Ac].
研究领域:
高分子科学
·
材料化学
·
纤维素化学
·
绿色溶剂
·
薄膜材料
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·Vol. 43
·期 7
·3741-3749
·
IF 4.229
Xingcheng Hu,Ravi Muchakayala,Shenhua Song,Jingwei Wang,Jianjun Chen,Manlin Tan
Polymeric ionic liquid-based gel electrolyte films are a new generation of electrolyte materials for flexible energy storage device applications. In this work, Li-ion conducting gel electrolyte films are prepared with the polymeric ionic liquid poly(diallydimethylammonium) bis(trifluoromethane sulfonyl)imide (poly(DADMATFSI)) as the host polymer and the lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt as the dopant . The crystalline nature, thermal stability, ionic conductivity and electrochemical stability window of the polymeric electrolyte films are analyzed by various characterization techniques. It is found that the polymeric electrolyte films exhibit high flexibility and excellent thermal stability. Their room-temperature electrical conductivity increases with increasing LiTFSI concentration and reaches a high value of 1.00 × 10 −3 S cm −1 at 20 wt% LiTFSI. The ionic transference numbers of the polymeric electrolyte films are in the range of 0.98–0.99, indicating that they are perfect ion conductors. Finally, the electrochemical stability window of the 20 wt% LiTFSI-doped polymeric electrolyte film is determined as approximately 6 V, which is a promising value for flexible energy storage device applications.
研究领域:
材料科学
·
电化学
·
高分子化学
·
能源存储
·
功能材料
✓ 已验证
DOI
高影响因子