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磷钨酸/磺化聚醚醚酮质子导电复合膜 总被引:14,自引:0,他引:14
直接甲醇燃料电池(Direct methanol fuelcell,DMFC)作为各种用途的可移动动力源具有高效、清洁和燃料储运方便等优点,成为20世纪90年代以来研究与开发的热点。目前,这种电池的研究难点主要集中在催化剂不稳定和质子交换膜透醇上,DMFC膜不但要可传递质子和绝缘电子,还应具有 相似文献
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质子交换膜是直接甲醇燃料电池(DMFC)的关键组成部分. 通过磺化制备了磺化杂萘联苯聚醚酮(SPPEK)、磺化杂萘联苯聚醚砜(SPPES)和磺化杂萘联苯聚醚砜酮(SPPESK)三种含杂萘联苯结构的新质子交换膜, 测试了其热稳定性、质子导电性和甲醇透过性能. SPPESK的热分解温度比相近离子交换容量(IEC)的SPPEK和SPPES约低100 ℃, 三种膜均具有良好的导电和阻醇性能; 分别以三种膜为电解质组装DMFC考察了其性能, DMFC的开路电压随膜的阻醇性的提高而增大, 三种膜的开路电压均高于Nafion115膜, 但在较高电流密度的区域三种新膜的性能均比Nafion115膜差. 相似文献
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氧化石墨烯/聚合物复合质子交换膜(GO/Polymer blend PEM)是一种新型的质子交换膜,广泛应用于直接甲醇燃料电池(DMFC)中,已成为质子交换膜研究的热点之一。氧化石墨烯/聚合物复合质子交换膜具有较高的传导质子率、力学性能、阻醇性能和电池性能。本文综述了氧化石墨烯(GO)处理方法、氧化石墨烯/聚合物复合质子交换膜制备方法,氧化石墨烯/聚合物复合质子交换膜的质子传导、阻醇、离子交换容量和电池的性能,氧化石墨烯/聚合物复合质子交换膜质子传递机理及阻醇机理。 相似文献
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质子导体的研究近年来受到了广泛的关注,具有质子传导能力的电解质材料可广泛地应用于燃料电池、电解池、电化学反应装置以及传感器等领域,特别是作为质子交换膜燃料电池(PEMFC)的核心组件之一的质子交换膜越来越受到人们的重视。Nafion(Du Pont)全氟磺酸膜是目前广泛用于PEMFC中的一种质子导体。Nafion全氟磺酸膜具有优异的化学稳定性以及在较低温度条件下高的质子电导率,然而其高昂的价格、差的高温性能以及用于直接甲醇燃料电池(DMFC)中时的高甲醇渗透率阻碍了DMFC商业化发展。 相似文献
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磺化酚酞型聚醚砜膜的制备及其阻醇和质子导电性能 总被引:7,自引:0,他引:7
直接甲醇燃料电池 (Directmethanolfuelcell,DMFC)以高效、清洁和燃料储运方便等优点适宜于作为各种用途的可移动动力源 ,成为 2 0世纪 90年代以来研究与开发的热点[1,2 ] .目前 ,这种电池的研究难点主要集中在催化剂不稳定和质子交换膜透醇上 .一张好的DMFC膜不但要可传递质子、绝缘电子 ,还应具有良好的阻醇性能 .如果膜的阻醇性能不好 ,甲醇会穿过膜到达阴极 ,与氧直接反应而不产生电流 ,不但造成燃料的浪费 ,同时也影响阴极的正常反应 ,使电池效率下降[3 ] .目前广泛应用于燃料电池中的Nafion 系列膜是由美国DuPont公司生产的一种… 相似文献
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1引言
直接甲醇燃料电池(DMFC)被认为是最适合发展可移动电源的选择之一,目前困扰DMFC发展的主要问题之一是所使用的质子交换膜(主要是杜邦公司的Nation膜)的阻醇性能较低。磺化聚醚醚酮膜(SPEEK)特有的微观结构使其阻醇性能明显的优于Nation膜,而较低的质子传导率、较差的机械性能以及溶胀等缺点限制了它的应用;本文通过在其中加入二氧化硅(SiO2)和磷钨酸(PWA)制备磺化聚醚醚酮/二氧化硅/磷钨酸导电复合膜,并考察了二氧化硅及磷钨酸对复合膜溶胀性能、质子传导率及机械性能的影响。 相似文献
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甲醇溶液浓度对于直接甲醇燃料电池(DMFC)的性能具有重要影响。 本文旨在建立一种能在电源系统中有效控制甲醇浓度的策略。 通过构建电池内甲醇物料守恒和热守恒方程,确定了基于电量和温度这两个参数的甲醇浓度控制策略。 通过测试温度-浓度关系验证了控制策略的可行性。 结果表明,采用该策略,DMFC电源系统稳定运行超过420 min;合适的甲醇浓度范围为0.70~0.87 mol/L。 该策略完成了甲醇浓度控制的目标,并将在电源系统中发挥重要作用。 相似文献
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Journal of Solid State Electrochemistry - A mathematical model is developed to study the transient leakage current in a direct methanol fuel cell (DMFC) system. The DMFC is divided into five... 相似文献
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直接甲醇燃料电池(DMFC)通常采用空气中氧气作为氧化剂,但空气中硫化物、氮化物等污染物会对电池性能造成影响. 本文采用恒流放电曲线、极化曲线、循环伏安扫描(CV)和电化学阻抗谱(EIS)等方法,研究SO2对DMFC电池性能影响,分析其毒化作用机制. 研究表明,SO2毒化导致催化剂电化学活性面积(ECSA)减小,氧还原反应(ORR)电荷转移电阻增大,从而造成DMFC电池开路电压和工作电压加速衰减,峰值功率密度减小. 进一步探究了三种恢复策略,空气吹扫与I-V变载操作都只能实现电池性能的部分恢复,CV扫描可完全恢复电池性能. 相似文献
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Nicholas W. DeLuca Yossef A. Elabd 《Journal of Polymer Science.Polymer Physics》2006,44(16):2201-2225
The direct methanol fuel cell (DMFC) has the potential to replace lithium‐ion rechargeable batteries in portable electronic devices, but currently experiences significant power density and efficiency losses due to high methanol crossover through polymer electrolyte membranes (PEMs). Numerous publications document the synthesis and characterization of new PEMs for the DMFC. This article reviews this research, transport phenomena in PEMs, and experimental techniques used to evaluate new PEMs for the DMFC. Although many PEMs do not show significant improvements over Nafion®, the benchmark PEM in DMFCs, experimental results show that several new PEMs exhibit lower methanol crossover at similar proton conductivities and/or higher DMFC power densities. These results and recommendations for future research are discussed. © 2006 Wiley Periodicals, Inc. J Polym Sci Parts B: Polym Phys 44: 2201–2225, 2006 相似文献
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Direct methanol fuel cells (DMFC) generally use oxygen as an oxidant.Contaminants such as sulfides and nitrides in the air can affect the performance of the DMFC.In this work, the effects of SO2 on the performance of DMFC were investigated and the mechanism of poisoning was analyzed, by means of constant current discharge curve, polarization performance curve, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS).In the CV scan, the permeated methanol was oxidized at a low potential to eliminate its effect on the SO2 poisoning behavior test.The results showed that the SO2 poisoning resulted in a decrease in the electrochemical activity surface area (ECSA) of the catalyst.Meanwhile, the EIS data indicated that the poisoning led to an increase in the charge transfer resistance of the oxygen reduction reaction (ORR).Therefore, the poison accelerated decay of the open circuit voltage and operating voltage of the DMFC, and decreased the peak power density.Further investigations of three recovery strategies, dry air purging and load-shifting I-V operations could only partially restore the performance of DMFC.However, CV scanning could accomplish the recovery more completely. © 2018 Journal of Electrochemistry. All rights reserved. 相似文献
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Shao ZG Zhu F Lin WF Christensen PA Zhang H 《Physical chemistry chemical physics : PCCP》2006,8(23):2720-2726
PtRu/Ti anodes with varying Pt ratio Ru ratio were prepared by electrodeposition of a thin PtRu catalyst layer onto Ti mesh for a direct methanol fuel cell (DMFC). The morphology and structure of the catalyst layers were analyzed by SEM, EDX and XRD. The catalyst coating layer shows an alloy character. The relative activities of the PtRu/Ti electrodes were assessed and compared in half cell and single DMFC experiments. The results show that these electrodes are very active for the methanol oxidation and that the optimum Ru surface coverage was ca. 9 at.% for DMFC operating at 20 degrees C and 11 at.% at 60 degrees C. The PtRu/Ti anode shows a performance comparable to that of the conventional carbon-based anode in a DMFC operating with 0.25 M or 0.5 M methanol solution and atmosphere oxygen gas at 90 degrees C. 相似文献
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Guo-Bin Jung Cheng-Hsin Tu Pei-Hung Chi Ay Su Fang-Bor Weng Yur-Tsai Lin Yu-Chun Chiang Chi-Yuan Lee Wei-Mon Yan 《Journal of Solid State Electrochemistry》2009,13(9):1455-1465
An experimental and simulation research had been performed to investigate the performance as well as the flow distribution
in the cathode flow field in the case of direct methanol fuel cells (DMFCs). The gas was well distributed in serpentine flow
field, whereas stagnation of the gas was observed in parallel flow field. These would contribute to the cell performance greatly
due to mass transfer effect when the cells start operating. In addition, the durability test of DMFC was drastically affected
in parallel flow field due to poor ability to drain flooded water produced electrochemically at cathode and crossover from
anode. In addition, pressure drops of different flow fields were also investigated to evaluate their contribution and feasibility
as an economic application for DMFC. DMFC with serpentine flow field featuring higher pressure difference resulted in a larger
parasitic energy demand. However, the optimal flow field designs are needed to balance the performance and pressure loss to
achieve a uniform fluid distribution and simultaneously minimize energy demand for mass transport. Consequently, flow field
with grid pattern appears to be the optimal design for the DMFC cathode. 相似文献