HIGH PERFORMANCE POLYMERS
·
2016
·
IF 1.045
Yang Liu,Pengfei Huo,Jiannan Ren,Guibin Wang
A series of novel organic–inorganic hybrid proton exchange membranes (PEMs) were prepared from the sulfonated poly(arylene ether sulfone) with 4-amino phenyl pendant groups (Am-SPAES), (3-isocyanatopropyl) triethoxysilane (ICPTES), and 3-(trihydroxysilyl) propane-1-sulfonic acid with covalent bonds to form network using a sol-gel method. The obtained cross-linked hybrid membranes (Am-SPAES/I-SiO2-S) displayed excellent solvent resistance and thermal and mechanical stability. The Am-SPAES/I-SiO2-S membranes with cross-linking network exhibited a higher proton conductivity (0.043 S cm−1 at 20°C) than PEMs without covalent bonds (Am-SPAES/SiO2-S) and the swelling ratio maintained below 17.00% even at 100°C. Most importantly, all of the obtained membranes showed considerably lower methanol permeability than that of Nafion 117. In addition, the chemical structures and morphologies of the hybrid membranes were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively.
研究领域:
材料科学
·
燃料电池技术
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2026
·
IF 9.2
Shiyi Peng,Jiabin You,Xiaojing Cheng,Yongjian Su,Huiyuan Li,Shuiyun Shen,Junliang Zhang
Local oxygen transport resistance in the catalyst layer, primarily caused by the dense ionomer film near the catalyst surface due to specific adsorption of sulfonate groups (-SO 3 - ), remains a major limiting factor for PEMFC performance. Here, we propose a molecular regulation strategy using an ionic liquid (IL) to mitigate the detrimental effects of Nafion ionomer. IL cations electrostatically interacts with SO 3 − , weakening ionomer adsorption on platinum (Pt) surfaces and promoting hydrophilic–hydrophobic phase separation of the Nafion matrix, creating more amorphous regions that facilitate local oxygen transport. Consequently, the IL-modified membrane electrode assemblies exhibit a 35.3% reduction in local oxygen transport resistance and a 1.41-fold enhancement in peak power density. Furthermore, Coulombic interactions stabilize the IL within the catalyst layer, ensuring a uniform ionomer distribution and enhanced surface hydrophobicity. Thus the electrodes exhibit remarkable durability. This study provides a novel interfacial engineering solution to improve both PEMFC performance and long-term stability.
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2022
·
IF 9.221
Weijia Li,Lingchu Huang,Huaiyuan Sun,Bin Wang,Qi Lu,Xishuang Liang,Fangmeng Liu,Fengmin Liu,Peng Sun,Geyu Lu
The development of high-performance H 2 gas sensors is a challenge for safe operation in the high-risk area of flammable and explosive. In this work, Pd/CF is used as a sensing material in fuel cell type sensors and the effect of Pd loading (5 wt%, 10 wt% and 20 wt%) on the sensors’ performance is investigated. The sensor based on Pd(10 wt%)/CF shows the best sensing performance which can be attributed to both the optimal balance of Pd content and utilization to produce the most active sites for the catalytic reaction and the highest conductivity of the membrane electrode assembly (MEA). These are confirmed by EDS images, cyclic voltammetry curve and complex impedance curves. The optimal sensor has a response value of about − 60 μA to 5000 ppm H 2 and a sensitivity of − 0.0131 μA/ppm to 200–10000 ppm H 2 at room temperature (25 °C). In addition, with the advantages of no heating, no external voltage, simple fabrication process, high linearity, good repeatability and long-term stability, the sensor in this work possesses very broad development prospect.
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2022
·
IF 4.291
Xiaojun Zhang,Sujun Yu,Manhong Li,Minglu Zhang,Chengwei Zhang,Man Wang
The structure and additives of ionic polymer-metal composite (IPMC) are important factors affecting its performance. Macropores and multi-walled carbon nanotubes (MCNTs) were introduced into multilayered IPMC actuators by an orderly mesh of silica spheres to enhance the IPMC actuator’s performance. The mechanical of membranes is improved a lot by the uniform combination of MCNTs and macroporous multilayered MCNTs/Nafion membrane. In particular, Young’s modulus for the macroporous multilayered MCNTs/Nafion membrane increases by 3.3 folds (from 262.6 MPa to 858.1 MPa), and the hardness increases by 4.4 folds (from 28.2 MPa to 123.9 MPa). Electromechanical results of the IPMC actuator increase respectively by 1.41 (33.5 mm) and 2.2 (19.2 mN) folds in the air under a DC voltage of 5 V, compared with typical IPMC actuators.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Aidi Han,Cehuang Fu,Xiaohui Yan,Junren Chen,Xiaojing Cheng,Changchun Ke,Junbo Hou,Shuiyun Shen,Junliang Zhang
With the wide use of platinum alloy electrocatalysts proton exchange membrane fuel cells, the dissolution of transition metal in the acid environment of catalyst layer becomes a major concern due to the decreased catalytic activity during long-term operation. Although great efforts have been done, few attention is paid to the effect of transition metal ion contamination of Nafion ionomer that wrapped around catalyst particles within catalyst layer which might greatly influence the proton conduction. To elucidate such effect, ultrathin Nafion film on SiO 2 model substrate is prepared via self-assembly method to represent the ionomer in fuel-cell catalyst layers, and the ultrathin film with specific thickness is further equilibrated in Co(NO 3 ) 2 /HNO 3 solutions with different Co 2+ concentration to achieve different doping level. Conductivity measurements demonstrate that the non-precious metal contamination severely worsens proton conduction of Nafion ionomer, but it is always ignored before. In addition, when the occupation of H + in Nafion ionomer is less than 50%, the activation energy shows a sharp increase, indicating a possible change in proton conduction mechanism.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 31
·16079-16088
·
IF 7.443
Yongheng Yin,Wanyu Deng,Hongyan Wang,Anping Li,Chongbin Wang,Zhongyi Jiang,Hong Wu
Hollow mesoporous silica microspheres with a uniform pore size and a large surface area are synthesized and functionalized by three kinds of amino acids with different acid–base pairs, including sulfonic acid–amino groups (HMS-Cys), phosphoric acid–amino groups (HMS-Phos) and carboxylic acid–amino groups (HMS-Asp). The incorporation of these microspheres into a Nafion matrix enhances the water uptake and adjusts the organic–inorganic interface and hydrophilic ionic domains inside the membranes. Microspheres with a hollow mesoporous structure endow the membranes with strong water retention ability. The proton conductivities of hybrid membranes are more than 8 times higher than that of recast Nafion at 40 °C and 20% RH after 90 min of testing. The acid–base pairs within the membranes work as proton donors and acceptors, and the retained water molecules are used as hydrogen-bonded bridges, which reduce the energy barrier for proton conduction. At the filler content of 4 wt%, the HMS-Cys embedded membrane shows the highest proton conductivity of 1.19 × 10−1 S cm−1 (30 °C, 100% RH). In addition, hybrid membranes incorporated with amino acid functionalized HMS show small reliance on humidity. The proton conductivities of all the hybrid membranes are ∼5.29–11.1 times higher than that of the recast Nafion under 26.1% RH and 80 °C.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2025
·
IF 9.2
Xianda Zhang,Yaotian Yan,Yangshuo Liu,Chun Li,Jian Cao,Junlei Qi
CO2 reduction reaction (CO2RR) has been considered as a promising process that can compensate CO2 emission and convert it into value-added chemicals. In preparation of CO2RR catalytic electrode, Nafion is a common binder but its effect in catalytic process is usually ignored. Herein, we proposed the bifunction of Nafion in CO2RR based on its molecular structure and successfully developed a CO2-affinitive surface of Micro-Ag /Nafion by controlling the content of Nafion, which exhibited a superior CO faradaic efficiency (FECO) of 95.07% at -0.9 V (vs. RHE). This excellent FECO and 2 times of CO partial current density (jCO) in flow-cell proved its industrial prospect. Its splendid selectivity of CO2RR was attributed to the selective polarization of CO2 molecule at Nafion, which resulted in the 6.8 times higher adsorption energy (Eads) of CO2 than H2O. Therefore, CO2RR gained an advantage in the competitive reaction.Nafion was recognized as a favorable transporter for CO2 on the surface of metal catalyst. Our work describes the bifunctional role of Nafion in CO2RR electrode and it will contribute to optimize the design of metal/Nafion catalytic material for CO2RR.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2014
·
IF 4.908
Xiangguo Teng,Jicui Dai,Jing Su,Geping Yin
Fluorocarbon surfactant (potassium nonafluoro-1-butanesulfonate) is employed to prepare the Nafion/fluorocarbon (N/FC) membranes for all vanadium redox flow batteries (VRFB). N/FC membranes with different FC surfactant mass ratios were successfully prepared by a solution casting method. The addition of FC surfactant has effectively suppressed the vanadium ions permeability and improved the proton conductivity of Nafion . The N/FC membrane with 5 wt% of FC surfactant (N/FC—5%) exhibits the highest ion selectivity (ratio of proton conductivity to permeability) of 2.0×10 6 S min cm −3 , which is 2.1 times higher than that of pure recast Nafion (r-Nafion) membrane (9.7×10 5 S min cm −3 ). Consequently, both coulombic efficiency ( CE ) and voltage efficiency ( VE ) of the VRFB with N/FC—5% membrane are higher than that of the VRFB with r-Nafion membrane. The average energy efficiency (product of CE and VE ) of the VRFB with N/FC—5% membrane is 11% higher than that of the VRFB with r-Nafion at current density of 40–80 mA cm −2 .
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2019
·
IF 5.162
Jing Gao,Qinjun Shao,Jian Chen
Single-ion conducting solid polymer electrolytes are expected to play a vital role in the realization of solid-state Li metal batteries . In this work, a lithiated Nafion (Li-Nafion)-garnet ceramic Li 6.25 La 3 Zr 2 Al 0.25 O 12 (LLZAO) composite solid electrolyte (CSE) membrane with 30 µm thickness was prepared for the first time. By employing X-ray photoelectron spectroscopy and transmission electron microscope , the interaction between LLZAO and Li-Nafion was investigated. It is found that the LLZAO interacts with the Li-Nafion to form a space charge layer at the interface between LLZAO and Li-Nafion. The space charge layer reduces the migration barrier of Li-ions and improves the ionic conductivity of the CSE membrane. The CSE membrane containing 10 wt% LLZAO exhibits the highest ionic conductivity of 2.26 × 10 −4 S cm −1 at 30 °C among the pristine Li-Nafion membrane, the membrane containing 5 wt%, 20 wt%, and 30 wt% LLZAO, respectively. It also exhibits a high Li-ion transference number of 0.92, and a broader electrochemical window of 0–+4.8 V vs. Li + /Li than that of 0–+4.0 V vs. Li + /Li for the pristine Li-Nafion membrane. It is observed that the CSE membrane not only inhibits the growth of Li dendrites but also keeps excellent electrochemical stability with the Li electrode. Benefitting from the above merits, the solid-state LiFePO 4 /Li cell fabricated with the CSE membrane was practically charged and discharged at 30 °C. The cell exhibits an initial reversible discharge specific capacity of 160 mAh g −1 with 97% capacity retention after 100 cycles at 0.2 C, and maintains discharge specific capacity of 126 mAh g −1 after 500 cycles at 1 C. The CSE membrane prepared with Li-Nafion and LLZAO is proved to be a promising solid electrolyte for advanced solid-state Li metal batteries .
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Yanli Zhou,Huanqing Zhang,Zhu Chang,Baoxian Ye,Maotian Xu
A highly sensitive electrochemical sensor for the simultaneous determination of clenbuterol (CLB) and salbutamol (SAL) was fabricated by the modification of graphene-Nafion (GN-Nafion) composite film on a glassy carbon electrode (GCE). Both CLB and SAL caused a pair of redox peaks at the GN-Nafion/GCE in 0.04 M Britton-Robinson buffer solution. Obvious anodic peak currents for the oxidation of both CLB and SAL were observed under the optimal condition. The difference of oxidation peak potentials for CLB and SAL was about 200 mV, which made it possible for simultaneous determination of these compounds using the GN-Nafion/GCE. The detection limit for CLB and SAL was 0.13 μM and 0.11 μM (S/N=3), respectively. The proposed method was applied to simultaneously detect CLB and SAL in pork meat with satisfactory results. Otherwise, the excellent reproducibility, stability and selectivity were obtained at the proposed electrode.
研究领域:
电化学
·
分析化学
·
食品安全
·
纳米材料
·
传感器
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2011
·Vol. 16
·期 4
·1473-1480
·
IF 2.234
Xu Ying,Wang Fei,Wang Le,Zhao Fangyuan,Yang Baocheng,Ye Baoxian
A novel voltammetric sensor, based on single-walled carbon nanotubes (SWNT) dispersed in Nafion and modified glassy carbon electrode (GCE), was fabricated and used to determine the trace amounts of dihydromyricetin (DMY). The electrochemical behavior of DMY at this sensor was investigated in 0.1 mol L −1 sulfuric acid solutions + 0.1 mol L −1 NaCl by cyclic voltammetry and squarewave voltammetry. Compared with bare GCE, the electrode presented an excellent response of DMY through an adsorption-controlled quasi-reversible process. Under the optimum conditions, the response peak currents were linear relationship with the DMY concentrations in the range of 1.0 × 10 −7 –1.0 × 10 −5 mol L −1 with a detection limit of 9 × 10 −8 mol L −1 . Based on this voltammetric sensor, a simple and sensitive electroanalytical method for DMY was proposed and applied to quantitative determination of DMY in Ampelopsis grossedentata samples. In addition, the oxidation mechanism was proposed and discussed, which could be a reference for the pharmacological action of DMY in clinical study.
研究领域:
分析化学
·
药理学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
·
2013
·Vol. 60
·期 8
·1019-1026
·
IF 0.879
Fei Wang,Xiang Yu,Haojie Li,Ming Li,Qimin Feng
A simple but highly snesitive electrochemical sensor for the determination of dihydromyricetin (DMY) based on graphene-Nafion nanocomposite film modified Glassy carbon electrode (GCE) was reported. The characteristic of the sensor was examined by scanning electron microscopic (SEM) and electrochemical impedance spectroscopy (EIS). Compares with bare GCE, pre-anodized glassy carbon electrode (GCE(ox)) and Nafion modified electrode, the sensor exhibited the more superior ability of detecting DMY, due to the synergetic graphene and Nafion. Other, the dependence of the current on pH, instrumental parameters, accumulation time and potential were investigated to optimize the experimental conditions in the determination of DMY. Under the selected conditions, the response peak currents were linear relationship with the DMY concentrations in the range of 8.0 × 10 −8 ∼ 2.0 × 10 −5 mol L −1 with a detection limit of 2.0 × 10 −8 mol L −1 . And, the method was also applied successfully to detect DMY in Ampelopsis grossedentata samples.
研究领域:
分析化学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）