RSC Advances
·
2015
·Vol. 5
·期 50
·39878-39883
·
IF 3.84
Cheng Feng,Yunhui Hao,Li Zhang,Ningzhao Shang,Shutao Gao,Zhi Wang,Chun Wang
Formic acid (FA) has tremendous potential as a safe and convenient source of hydrogen for renewable energy storage, but controlled and efficient dehydrogenation of FA by a robust solid catalyst constitutes a major challenge. In this report, a metal nanoparticle functionalized zeolitic imidazolate framework (ZIF) derived N-decorated nanoporous carbon (NPC) support was fabricated and used as an efficient FA decomposition catalyst for the first time. The resultant AgPd@NPC catalyst exhibited 100% H2 selectivity and high catalytic activity (TOF = 936 h−1) toward the dehydrogenation of formic acid at 353 K. The synergetic interaction between the metal nanoparticles and NPC greatly enhances the catalytic performance of the as-prepared catalyst.
研究领域:
催化化学
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能源材料
·
纳米材料
·
物理化学
·
氢能存储
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Xiaoxiao Zhang,Qingting Liu,Lei Xia,Dongyang Huang,Xudong Fu,Rong Zhang,Shengfei Hu,Feng Zhao,Xiao Li,Xujin Bao
To broaden the operating temperature range of phosphoric acid (PA) doped polybenzimidazole membrane-based proton exchange membrane fuel cells (PEMFCs) toward low temperatures, a novel series of poly(2,5-benzimidazole) (ABPBI)/sulfonated sepiolite (S-Sep) composite membranes (ABPBI/S-Sep) with low PA doping levels (DLs) were prepared via in-situ synthesis. The desirably enhanced mechanical, thermal, and oxidative stabilities of ABPBI/S-Sep composite membranes were achieved by constructing ABPBI chains arranged along the sepiolite (Sep) fibers and acid-base crosslinks formed between S-Sep fibrous particles and ABPBI chains. Benefiting from the richness of high temperature stable bound water and the excellent water absorbability of Sep particles that enable the formation of additive proton conducting paths, the composite membranes retained bounded PA and achieved much higher proton conductivities under both anhydrous and hydrous conditions compared to PA-doped ABPBI membranes. Proton conductivity values above 0.01 S/cm at 40–90 °C/20–98% RH conditions and 90–180 °C/anhydrous conditions as well as peak power density of 0.13 and 0.23 W/cm 2 at 80 and 180 °C with 0% RH, respectively from the ABPBI/2S-Sep composite membrane are more holistic compared to Nafion at low temperatures and polybenzimidazole-based membranes at high temperatures, respectively. The excellent properties of ABPBI/S-Sep composite membranes suggest them as prospective candidates for PEMFCs applications in a wide temperature range.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Junwang Zhang,Lili Song,Kunlan Li,Qingda An,Hao Ma,Liyu Yang,Ligang Wei
Water addition was found to enhance the thermal stability of alkylimidazolium–acetate ionic liquids (ILs). Especially in the case of high water content (30–50 wt%), few decomposition products can be observed in the 1 H NMR spectra even after treatment for 24 h at 150 °C. On the basis of this finding, lignin treatment of water and acetate IL mixtures (50–90 wt% IL content) were investigated at 150 °C. The addition of water, as opposed to pure IL treatment, can inhibit the lignin depolymerization into small fragments. Lignin degradation and the structure of regenerated lignin are more affected by cation types of ILs rather than the IL contents and pH values. In the case of 50–70 wt% 1-ethyl-3-methylimidazolium acetate–water system, the specific inter-unit linkages of lignin can be broken down, and regenerated lignin with a narrow polydispersity index (5.0–9.6) can be obtained.
研究领域:
绿色化学
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生物质转化
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高分子化学
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离子液体化学
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木质素化学
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可持续材料
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热化学转化
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Xinming Du,Zhe Wang,Wenchang Liu,Jingmei Xu,Zhaoyu Chen,Chunmei Wang
A series of phenolphthalein-based poly (arylene ether ketone) (PEK) copolymer are synthesized to prepare anion exchange membranes (AEMs). The ion group 1-vinyl imidazole is introduced on the unit of phenolphthalein-based as a hydrophilic segment and cross-linking agent. The structure of resulting membranes was investigated by 1 H NMR and FT-IR. The well-defined microphase-separated structures were verified by TEM and SAXS profiles. The cross-linked membrane of ImPEK-0.4 exhibits high hydroxide conductivity (0.0836 S/cm, at 80 °C), excellent mechanical performance (69.6 MPa) and the maximum swelling ratio is only 7.95% at 80 °C. Furthermore, the excellent alkaline stability is demonstrated by immersing the prepared membrane in 1 M NaOH at 40 °C for 400 h. The ionic conductivity is still high to 0.0381 S/cm for ImPEK-0.4. These results indicate that combining phase separation architecture and crosslinking may possess potential applications for alkaline fuel cells (AFCs).
研究领域:
高分子材料科学
·
电化学能源材料
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燃料电池技术
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膜分离工程
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聚合物化学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Jianxian Zeng,Zhihui Dong,Zhe Zhang,Yuan Liu
A surface-grafted imprinted ceramic membrane (IIP-PVI/CM) for recognizing molybdate (Mo(VI)) anion was prepared by surface-initiated graft-polymerization. Firstly, raw alumina ceramic membrane (CM) was deposited with SiO 2 active layer by situ hydrolysis deposition method. Subsequently, γ-methacryloxy propyl trimethoxyl silane (MPS) was used as a coupling agent to introduce double bonds onto the SiO 2 layer (MPS-CM). Then, 1-vinylimidazole (VI) was employed as a functional monomer to graft-polymerization onto the MPS-CM (PVI-CM). During the graft-polymerization, the influence factors of grafting degree of PVI were investigated in detail. Under optimum conditions (monomer concentration 20 wt%, temperature 70 °C, initiator amount 1.1 wt% and reaction time 8 h), the grafting degree of 20.39 g/100 g was obtained. Further, Mo(VI) anion was used as a template to imprint in the PVI-CM by employing 1,6-dibromohexane as a cross-linking agent, and then Mo(VI) was removed, obtaining the IIP-PVI/CM with many imprinted cavities for Mo(VI). Thereafter, static adsorption and dynamic separation properties of IIP-PVI/CM for Mo(VI) were studied. Results indicate that IIP-PVI/CM shows a specific selectivity for Mo(VI) with the adsorption capacity of 0.69 mmol/100 g, and the selectivity coefficient of IIP-PVI/CM is 7.48 for molybdate to tungstate anions. During the dynamic separation, IIP-PVI/CM has also good selectivity for separation of Mo(VI) and W(VI) anions.
研究领域:
环境化学
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材料科学
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分离科学
·
高分子化学
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无机分析化学
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DOI
高影响因子
PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES
·
2013
·Vol. 12
·期 9
·1628-1635
·
IF 2.923
Li Qiu-Ping,Yan Bing
A series of luminescent polymers are synthesized by incorporating rare earth complex units into polymer matrices. Firstly, we functionalize the selected polymer matrices with the imidazolium moieties, and then introduce the rare earth tetrakis(β-diketonate) complexes into polymer matrices through a mild anion exchange method. The resulting materials are characterized by FTIR, XRD, EDAX, SEM, thermogravimetric analysis, luminescence excitation spectra and emission spectra, luminescence lifetime measurements and diffuse reflectance UV-Vis spectra. The photoluminescence measurements indicate that all these rare earth complex functionalized polymers exhibit a characteristic luminescence emission originating from the corresponding rare earth ions. Among the hybrids, the europium tetrakis(TTA) complex functionalized polymers show remarkable luminescence quantum yields and relatively long 5 D 0 lifetimes at room temperature.
研究领域:
材料化学
·
高分子科学
·
光物理学
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无机功能材料
·
发光材料
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Yuhua Dong,Jianbin Zheng
The work presented that by regulating the proportion between cobalt and 2-methylimidazole in distilled water, a series of Co-based imidazolate framework compounds with diverse shapes were synthesized at ambient temperature. The morphology and structural characteristics of the compounds were surveyed by scanning electron microscope, energy disperse spectra, powder X-ray diffraction and N 2 absorption-desorption. It was found by cyclic voltammetry that the zeolitic imidazolate framework compound synthesized at a ratio of 1:20 had the best electrocatalytic activity to H 2 O 2 reduction, therefore, the compound was chosen to fabricate a H 2 O 2 electrochemical sensor. Electrochemical studies indicated that the sensor had a determination limit of 0.7 μM and short response time within 3 s. The catalytic current was linear with H 2 O 2 concentration from 2.5 to 212.5, 212.5 to 1662.5 and 1662.5 to 6662.5 μM and the sensitivity were 12.2, 5.3 and 2.4 μA mM −1 cm −2 , respectively. Furthermore, the proposed sensor showed a good anti-interference capacity, repeatability and stability.
研究领域:
分析化学
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材料科学
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电化学
·
生物传感器
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纳米材料
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环境监测
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2012
·Vol. 125
·期 4
·2867-2873
·
IF 1.289
Yehai Yan,Na Lu,Jian Cui,Jinfang Zhang
A new fluorescent copolymer, poly(1-vinylimidazole- co -(1-pyrene) methyl 2-methyl-2-propenote) (VI- co -PyMMP), has been designed and synthesized by a free-radical copolymerization of VI and PyMMP as well as characterized using ultraviolet (UV), Fourier transform infrared spectroscopy (FTIR), 1 H NMR, and fluorescence spectroscopies. The monomer reactivity ratios are determined by two methods of Fineman-Ross ( r 1 = 0.28 ± 0.04 for VI, r 2 = 1.32 ± 0.11 for PyMMP) and Kelen-Tüdös ( r 1 = 0.23 ± 0.05, r 2 = 1.22 ± 0.12). Based on the reactivity ratios, the monomer sequence lengths and Q and e for PyMMP monomer are further calculated. The results suggest that the copolymerization of VI and PyMMP is a nonideal copolymerization without an azeotropic point (i.e., r 1 < 1, r 2 > 1 and r 1 r 2 < 1) and has a low alternation tendency. The conclusions drawn in this work may not only direct the later synthesis of the copolymers but also enrich the database of free-radical copolymerization. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
研究领域:
高分子化学
·
功能高分子
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荧光材料
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聚合物合成
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材料化学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2013
·
IF 3.535
Kelei Zhuo,Yujing Wei,Jingjing Ma,Yujuan Chen,Guangyue Bai
Several alkylmethylimidazolium tetraphenylborates (C n mim-TPB, n = 2–10) were synthesized and explored as ion exchangers in plasticized PVC membranes with very attractive sensing behaviors. And then a series of ion-selective electrodes (ISEs) were prepared and their potentiometric properties were investigated. The proposed electrodes exhibited Nernstian responses to alkylmethylimidazolium-based ionic liquid cations [C n mim] + . These electrodes were successfully applied in the determination of thermodynamic parameters of ionic liquids in aqueous solutions and in the detection of [C n mim] + in tap water and distilled water with satisfactory results. For the as-prepared ISEs, one special and important relationship was observed between the selectivity coefficients and the length of alkyl side chains of interfering cations [C n mim] + . The proper understanding of this relationship should facilitate the development of new method for the determination of ionic liquids using ISEs.
研究领域:
分析化学
·
电化学
·
环境监测
·
离子传感
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药物分析
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水处理
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生物传感器
·
物理化学
✓ 已验证
DOI
高影响因子
TETRAHEDRON-ASYMMETRY
·
2010
·
IF 2.625
Zhen-Wei Zhang,Gui Lu,Miao-Miao Chen,Ning Lin,Yong-Bo Li,Tamio Hayashi,Albert S.C. Chan
The first asymmetric Mannich-type reaction of methyl isocyanoacetate with N -sulfonylimines catalyzed by cinchona alkaloid derivatives yielded 2-imidazolines with high diastereoselectivities and good enantioselectivities (up to >99:1 dr and 70% ee). This reaction provided a convenient route to access various substituted 2-imidazoline-4-carboxylates and related α,β-diamino acids in high enantiomeric purities.
研究领域:
有机化学
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药物化学
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不对称合成
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催化化学
·
生物有机化学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2013
·
IF 3.365
Jing Cuan,Bing Yan
In our work, we achieve the multi-component assembly of novel kinds of photofunctional hybrid materials with polyoxometalates (POMs, Na 9 EuW 10 O 36 ·32H 2 O (EuW 10 O 36 9 - denoted as EuW10)) and benzoate (4-aminobenzoate, 4-hydroxybenzoate, 4-mercaptobenzoate) modified mesoporous silica through imidazolium ionic liquid (IL, 1-methyl-3-(trimethoxysilylpropyl) compound as double functional linkage. Using Pluronic P123 surfactant as a template, benzoate functionalized SBA-15 mesoporous host is synthesized as result of the co-condensation of tetraethoxysilane (TEOS) and benzoate modified siloxane as precursor. We fabricate POM into the framework of functionalized SBA-15 mesoporous silica with IL. Here IL behaves as double linkage, which both interact with PMO with electrostatic force through ion exchange and form covalent bond to the functionalized SBA-15 mesoporous silica through its alkoxy group after cohydroxylysis and copolycondensation process. Tb 3+ is further introduced into the above hybrid system through coordination bond to carboxylate group of benzoate unit, which can be expected to modify luminescence color and to obtain close white luminescence. The physical characterizations prove these hybrid materials possess high surface area, uniform mesoporous structure, good crystallization and relatively excellent luminescence properties.
研究领域:
无机化学
·
材料化学
·
纳米功能材料
·
光物理学
·
配位化学
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溶胶-凝胶科学
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稀土发光材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 12
·6972-6980
·
IF 3.108
Xiaohui Liu,Qian Zhu,Qiuyan Zhang,Yanguang Zhang,Chen Ding
Over the past few years, ionic liquids (ILs) have been widely reported as reaction media for reverse atom transfer radical polymerization (ATRP). In particular, almost all the ILs with the structure [Hmim][RCOO] (R represents an alkyl group) have been used as ligands for a reverse ATRP system. However, the facile, simple and low-cost ILs, 1-alkyl-3-methylimidazole chloride ([Rmim][Cl]), have rarely been employed as ligands for reverse ATRP. In this article, a [Rmim][Cl] was successfully employed as a ligand for the reverse ATRP of methyl methacrylate with Fe(III) as catalyst and 2,2′-azobisisobutyronitrile as initiator. The key to success is to adjust the FeCl3/[Rmim][Cl] molar ratio value to 1 : 1. The results indicated that the polymerization with [Rmim][Cl] as a ligand proceeded in a controlled/“living” fashion, as evidenced by the first-order kinetic plot, low polydispersity index values, and increase in polymer molecular weight with monomer conversion. The effects of various experimental parameters, including different catalysts, reaction temperatures, solvents, and molar ratios of FeCl3/[Rmim][Cl], on the polymerization were investigated in detail. Furthermore, 1H NMR and gel permeation chromatography analyses confirmed the halogen-containing chain-end functionality of the resultant polymer.
研究领域:
高分子化学
·
有机合成
·
催化化学
·
功能材料
·
可控自由基聚合
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）