燃料电池用碱性膜材料的研究进展

碱性膜直接甲醇燃料电池因为结合了质子交换膜燃料电池和液体碱燃料电池的优点而产生自身独特的性质,使其可以在一定程度上弥补质子交换膜燃料电池以及液体碱燃料电池的缺点而尤其引人关注。其中碱性膜电解质为碱性膜燃料电池的核心组件,其性能直接关系到燃料电池的性能及寿命。截至目前,关于碱性膜材料的制备及应用方面的报道较多,涉及的碱性膜电解质的种类也较多。本文以燃料电池用碱性膜电解质为综述内容,对国内外关于碱性膜电解质的研究报道进行系统的梳理和介绍。     

碱性燃料电池用阴离子交换膜的研究进展

阴离子交换膜燃料电池（AEMFCs）因其具有环境友好、可使用非贵金属催化剂、电极反应速率快等特点而受到广泛关注。阴离子交换膜（AEMs）是AEMFCs的核心部件,其性质决定着燃料电池的性能、能量效率和使用寿命。从具有不同骨架结构的聚合物出发,介绍了聚苯醚、聚芳醚砜、聚烯烃和聚苯并咪唑等不同聚合物骨架结构的阴离子交换膜的制备、性能和应用,同时对具有不同聚合物骨架结构的阴离子交换膜在应用方面存在的问题及应用前景进行了评论和展望。     

Application of sodium conducting membranes in direct methanol alkaline fuel cells

A study of a direct methanol alkaline fuel cell (DMAFC) operating with sodium conducting membranes is reported. Evaluation of the fuel cell was performed using membrane electrode assemblies incorporating carbon supported platinum catalysts and Nafion^® 117 and 112 membranes. A membrane electrode assembly was also prepared by the direct chemical deposition of platinum into the surface region of the membrane. Evaluation of the chemically deposited assembly showed it to be less active than those based on carbon supported catalysts. SEM &; TEM analysis indicate that this behaviour is due to the low surface area of the chemically deposited catalyst layer. The fuel cell performance with Nafion membranes is reported and is not as good as achieved with hydroxide ion conducting membranes suggesting that Nafion may not be suitable for DMAFC operation.     

Composite anion exchange membrane for alkaline direct methanol fuel cell: Structural and electrochemical characterization

A copolymer of 4‐vinylpyridine (4‐VP) and styrene was synthesized by radical mass polymerization using 2,2′‐azobisisobutyronitrile as initiator. An insoluble (linear) pyridinium‐type polymer was prepared by the reaction of P (4VP–St) with 1‐bromooctane. An anion exchange membrane was prepared using a composite of pyridinium‐type polymer and a fibrous woven structure for use in electrochemistry. The composite membrane was characterized by X‐ray diffraction, tensile strength, scanning electron microscopy, and electrochemistry measurements. The experimental results showed that the fibrous woven product had improved the tensile strength more than had the membrane made of a pyridinium‐type polymer alone. The composite membrane was used in alkaline fuel cells, and its properties were measured by electrochemical analysis. The ionic conductivity of the membrane was acceptable, but its performance as a direct methanol fuel cell (DMFC) was not. The primary reason for this was analyzed, and research is ongoing, with analysis to be discussed in later reports. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2248–2251, 2006     

Cardo poly(arylene ether sulfone) block copolymers with pendant imidazolium side chains as novel anion exchange membranes for direct methanol alkaline fuel cell

A series of phenolphthalein-based cardo poly(arylene ether sulfone) (PES) block copolymers containing pendant imidazolium group (PI-PESs) were synthesized as novel anion exchange membranes for direct methanol alkaline fuel cells. These PI-PESs combine the advantages of pendant anion conductors on the polymer side chains with the thermochemical stabilities of the imidazolium group, showing high hydroxide conductivity, together with good physical and chemical stability under basic conditions. The hydroxide conductivity over 0.03 S/cm at 20 °C and 0.1 S/cm at 80 °C was obtained for the PI-PES membranes. In addition, PI-PES membranes show low permeability to methanol (below 6.74 × 10⁻⁸ cm²/s) and very high selectivity (over 3.7 × 10⁵ S·s/cm³). These properties make the PI-PESs promising candidate materials for anion exchange membranes for direct methanol alkaline fuel cells.     

Preparation and characterisation of Pt deposition on ion conducting membrane for direct methanol fuel cell electrodes

Membrane-electrode assemblies (MEAs) for direct methanol fuel cells (DMFC) have been prepared by depositing platinum on the surface of solid polymer electrolytes (SPE). Chemical and electrochemical depositions were used to achieve good adhesion between platinum particles and the SPE and for reducing the contact resistance. Platinum particle structure and composition were investigated by means of SEM and EDX. Cyclic voltammetry (CV) and methanol oxidation tests were used to determine the electrochemical characteristics of the Pt-SPE electrodes which can be applied in DMFC. Overall the electrodes produced by chemical and electrochemical deposition of Pt onto the membranes are not as active as those produced by hot pressing carbon supported Pt catalyst layers onto the membrane.     

Imidazolium functionalized poly(vinyl alcohol) membranes for direct methanol alkaline fuel cell applications

In this study, imidazolium functionalized poly(vinyl alcohol) (PVA) was synthesized by acetalization and direct quaternization reaction. Afterwards, composite anion exchange membranes based on imidazolium‐ and quaternary ammonium‐ functionalized PVA were used for direct methanol alkaline fuel cell applications. ¹H NMR and Fourier transform infrared spectroscopy data indicated that imidazole functionalized PVA was successfully synthesized. Inductively coupled plasma mass spectrometry data demonstrated that the imidazolium structure was efficiently obtained by direct quaternization of the imidazole group. Composite anion exchange membranes were fabricated by application of the functionalized PVA solution on the surface of porous polycarbonate (PC) membranes. Fuel cell related properties of all prepared membranes were investigated systematically. The imidazolium functionalized composite membrane (PVA‐Im/PC) exhibited higher ionic conductivity (7.8 mS cm^?1 at 30 °C) despite a lower water uptake and ion exchange capacity value compared to that of quaternary ammonium. In addition, PVA‐Im/PC showed the lowest methanol permeation rate and the highest membrane selectivity as well as high alkaline and oxidative stability. Dynamic mechanical analysis results reveal that both composite membranes were mechanically resistant up to 10⁷ Pa at 140 °C. The superior performance of imidazolium functionalized PVA composite membrane compared to quaternary ammonium functionalized membrane makes it a promising candidate for direct methanol alkaline fuel cell applications. © 2020 Society of Chemical Industry     

Tetrazole tethered polymers for alkaline anion exchange membranes

Poly(2,6-dimethyl-1,4-phenylene oxide) was tethered with a 1,5-disubstituted tetrazole through a quaternary ammonium linkage. The formation of a tetrazole-ion network in the resulting polymers was found to promote the hydroxide ion transport through the Grotthus-type mechanism.

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直接甲醇燃料电池用阻醇质子交换膜研究进展

直接甲醇燃料电池是近十年兴起的新型燃料电池,并以其独特的优点引起了人们广泛的关注。作为其重要组成部分的质子交换膜的性质是影响电池性能的关键因素。本文在介绍近两年质子交换膜研究最新进展的基础上,综述了天然聚合物用作质子交换膜材料的研究情况,并分析了其优劣势及应用前景。     

燃料电池用阴离子交换膜分子结构研究进展

阴离子交换膜（AEMs）作为燃料电池的核心部件,其发展得到了普遍关注。然而,AEMs中聚合物骨架和阳离子基团无序的直接相连的结构导致了膜在应用过程中存在离子电导率低、碱稳定性差和机械性能不足等问题,因此对连接二者的分子结构进行设计,开发综合性能优异的AEMs很有必要。本文介绍了AEMs选择性透过的基本机理,并从不同的分子结构出发,总结了近年来应用较为广泛的嵌段结构、接枝结构、交联结构、局部高密度结构以及由局部高密度结构与其他三种结构组成的复合结构AEMs的研究进展;从离子电导率、碱稳定性、机械性能以及吸水率等方面对AEMs的性能提升进行了归纳,重点关注AEMs离子电导率和吸水率的权衡问题,并从分子结构及其组合使用的角度对燃料电池用AEMs的未来发展方向进行了展望。     

高稳定碱性离子膜分子设计研究进展

以阴离子交换膜（碱性离子膜）为基础的能量转化与储能过程十分重要,包括碱性膜燃料电池、碱性膜电解水制氢等,该类电膜过程对未来能源结构会产生深远影响。现有阴离子交换膜存在耐碱性差、性能衰减显著的问题,严重制约高效能源储存及转化技术发展。为了获得高稳定的碱性离子膜,近年来,围绕耐碱高分子材料的分子设计开展大量工作。本综述从碱性膜材料的高分子骨架和阳离子基团两个角度出发,针对膜材料耐碱性,重点阐述聚烯烃和聚芳基的主链结构,以及非金属中心、金属中心,两类阳离子的分子结构设计策略,展望高稳定碱性膜的结构设计规律及主要挑战,为设计与合成高性能碱性离子膜,满足清洁能源转化与储能膜过程提供新思路。     

Crosslinked anion exchange membrane with improved membrane stability and conductivity for alkaline fuel cells

As a core component of anion exchange membrane (AEM) fuel cells, it has practical significance to improve the performance of AEMs. However, it is difficult to obtain AEM with both good stability and high conductivity. In this study, a series of AEMs were prepared by chloromethylation, quaternization, and crosslinking reactions. The quaternization reaction was carried out first to ensure that there are abundant quaternary ammonium groups on AEM and enhance the conductivity of membrane. N,N,N′,N′-tetramethylethylenediamine was used as a crosslinker to improve membrane stability and mechanical property. A simple, mild, and cost-effective AEM synthetic route was developed. This strategy achieves a certain balance of electrochemical and physical properties. The effect of the crosslinking reactions on the property of membrane was evaluated. Crosslinked membranes have better dimensional stability (water uptake: 20.2% and swelling ratio: 2.1%), mechanical properties (55.84 MPa), and alkaline stability because crosslinked structures result in large steric hindrance. The mutually independent quaternization and crosslinking reaction do not affect the electrochemical performance of membranes; in the crosslinking reaction stage, crosslinker also reacted as quaternization agent and increased the number of reactive groups in AEM. Thus, the resulting crosslinked AEM exhibits higher ion exchange capacity and ionic conductivities (46.4 mS cm⁻¹). © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48169.     

阴离子交换膜改性及抗污染性能研究进展

电渗析技术应用于工业废水脱盐时,废水中有机物及其它杂质组分等会造成膜污染,进而影响脱盐性能。电渗析膜污染防治对促进电渗析在工业废水处理中的应用有重要意义。相比于阳离子交换膜,阴离子交换膜更易形成有机污染,且更严重。阴离子交换膜污染主要由腐殖酸、牛血清蛋白、阴离子表面活性剂等有机物造成,污染过程主要受静电作用、亲和作用和几何因素的影响。膜改性提高阴离子交换膜的抗污染性能是电渗析膜污染防治的有效方法,目前已有许多有关膜改性提高阴离子交换膜抗污染性能的报道。膜改性方法主要有化学改性法、等离子体改性法、表面涂覆改性法、电沉积改性法、自聚合改性法及改进基膜结构法等。本工作对阴离子交换膜改性及抗污染性能的研究进展进行了综述,对不同改性方法的优缺点进行了分析和评价。这些改性方法能提高阴膜表面的负电荷密度和亲水性、降低膜表面粗糙度和基膜含水率等,因此可以改善阴离子交换膜的抗污染性能。然而,目前研究获得的改性阴离子交换膜仍存在修饰层不稳定、抗污染性能不理想和性能测试不系统等缺点,需进一步优化改性方法、改性工艺、组分修饰及性能测试等,以获得抗污染性能稳定且效果良好的改性阴离子交换膜。     

Enhancing the stability of power generation of single‐chamber microbial fuel cells using an anion exchange membrane

BACKGROUD: A decreased power density could be observed in a single‐chamber microbial fuel cell (MFC) with a cation exchange membrane (CEM), as a result of pH‐associated problem and a precipitated salt‐associated problem, due to the transport of cations other than protons through the membrane to the cathode. To inhibit cation transport and enhance the stability of power generation, an anion exchange membranes (AEM) was applied in a single‐chamber MFC. RESULTS: After 70 days' operation, the power density dropped 29% in the MFC with an AEM (AMFC), smaller than 48% in the MFC with a cation exchange membrane (CMFC). The reason for this difference lay in internal resistance development. Membrane resistance in the AMFC remained the same but that in the CMFC was increased by 67 Ω, and the cathode resistance increase in the AMFC was 54 Ω, while that in the CMFC was 123 Ω. The precipitated cations on the cathode catalyst surface in the CMFC, which accounted for the resistance increase, were up to 84 times larger than that in the AMFC. CONCLUSION: Because of its capacity for inhibiting cations, the AMFC possessed more stable membrane and cathode resistances; thus an enhanced power generation was obtained. Copyright © 2009 Society of Chemical Industry     

富勒烯交联季铵化聚苯醚阴离子交换膜的制备

通过富勒烯C₆₀与乙二胺合成立体纳米分子C₆₀(EDA)₈,并以此为交联剂与三阳离子功能化聚苯醚制备了一系列交联型阴离子交换膜。C₆₀(EDA)₈中立体纳米结构有效地支撑了高分子链段,构建了更发达的离子通道,有效地提升了电导率。实验结果表明,随着C₆₀(EDA)₈加入量增加,交联膜的离子交换容量减小,而电导率却逐渐增加。当交联剂C₆₀(EDA)₈加入量为5%时,电导率提高了34%。此外,所制备的离子交换膜均表现出良好的抗溶胀能力、力学性能与耐碱性。     

降冰片烯类季铵型阴离子交换膜的制备

通过环状烯烃双键打开, 首尾相接形成聚合物的方法, 设计合成了含有季铵阳离子作为功能化基的降冰片烯衍生物单体QRPhNB, 通过开环异位聚合(ROMP)制备得到阴离子交换膜材料, 流延成膜后的分析结果表明:当单体与降冰片二烯1:2投料时所得到的阴离子交换膜的IEC值为1.26 mequiv·g^-1, 其最高离子传导率为20.05 mS·cm^-1;吸水率为14.3%。     

Comb-shaped diblock copolystyrene for anion exchange membranes

To improve the properties of diblock copolystyrene-based anion exchange membranes (AEMs), a series of AEMs with comb-shaped quaternary ammonium (QA) architecture (QA-PS_m-b-PDVPPA_n-xC where x denotes the number of carbon atoms in different alkyl tail chains and has values of 1, 4, 8, and 10 and C denotes carbon) were designed and synthesized via subsequent quaternization reactions with three different alkyl halogens (methyl iodide and N-alkane bromines (CH₃[CH₂] _x-1Br where x = 4, 8, and 10). Compared with triblock analogues quaternized with methyl iodide in our previous research, QA-PS_m-b-PDVPPA_n-xC (x = 4, 8, and 10) AEMs are more flexible with the introduction of a long alkyl tail chain; this probably impedes crystallization of the rigid polystyrene-based main chain and induces sterically adjustable ionic association. An increase in the pendant alkyl tail chain length generally led to enhanced microphase separation of the obtained AEMs, and this was confirmed using small-angle X-ray scattering and atomic force microscopy. The highest conductivity (25.5 mS cm⁻¹) was observed for QA-PS₁₂₀-b-PDVPPA₈₀-10C (IEC = 1.94 meq g^–1) at 20 °C. Furthermore, the water uptake (<30%) and swelling ratio (<13.1%) of QA-PS_m-b-PDVPPA_n-xC AEMs are less than half of these corresponding values for their triblock counterparts. The QA-PS₁₂₀-b-PDVPPA₈₀-10C membrane retained a maximum stability that was as high as 86.8% of its initial conductivity after a 40-day test (10 M NaOH, 80 °C), and this was probably because of the steric shielding of the cationic domains that were surrounded by the longest alkyl tail chains. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47370.     

Preparation and characterization of ABS/HIPS heterogeneous anion exchange membrane filled with activated carbon

Acrylonitrile‐butadiene‐styrene (ABS)/high impact polystyrene (HIPS) blend heterogeneous anion exchange membranes were prepared by phase inversion method using tetrahydrofuran as solvent and anion exchange resin powder as functional group agent. Activated carbon was selected as inorganic filler additive. The additive concentration effect on properties of the prepared membranes was studied. Ultrasonic method was used to help appropriate dispersion of particles in the membrane's matrix. Scanning optical microscopy showed that sonication has a significant influence on distribution of resin particles in the membrane matrix and makes it possible to form more uniform phase. Moreover, images showed a relatively uniform surface for membranes. The increase of activated carbon concentration in casting solution led to a decline in membrane water content. The ion exchange capacity, membrane potential, permselectivity, transport number, ion permeability, ionic flux, and current efficiency of prepared membranes all were increased initially by the increase in additive concentration up to 1% wt and then they showed decrease trend with higher increase in additive concentration from 1 to 4% wt. Conversely, the electrical resistance and energy consumption showed opposite trends. In addition, with more additive loading, the oxidative stability of membranes was slightly decreased and their thermal stability was increased. Membrane with 1% wt additive loading exhibited higher efficiency and electrochemical properties in comparison with other prepared membranes in this research. Furthermore, prepared membranes exhibited suitable electrochemical properties compared to a commercial heterogeneous anion exchange membrane with the same experimental conditions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

直接甲醇燃料电池

介绍了直接甲醇燃料电池的原理、结构,并与发展较早的氢气燃料电池进行优劣比较。针对近期商业化便携式燃料电池的技术指标,主要讨论了直接甲醇燃料电池在性能和成本上的现状和问题,并着重阐述了阳极催化剂和电解质膜(决定其性能的两个关键因素)的研发进展。