质子交换膜的传输通道微观结构对燃料电池性能的影响

质子交换膜燃料电池因其高效、高能量密度、快速启动等独特优势在便携电子设备及汽车动力装置等应用中极具发展潜力。质子交换膜内的传输通道由于对膜质子传导性能有重要影响而受到研究者们的广泛关注。构筑有序结构的质子传输通道,能够获得质子电导率与燃料渗透率、热稳定性、化学稳定性等性能均衡提升的新型质子交换膜材料。本文结合近年来质子传输通道的研究进展,对控制聚合物的相形态从而构筑有序质子传输通道的研究进行了综述,并针对不同相形态所形成的有序通道对膜及燃料电池性能的影响进行了分类与评述,最后对其发展趋势进行了展望。     

基于杂多酸的固体高质子导体*

杂多酸固体高质子导体在燃料电池、传感器和电显色装置等方面具有潜在的应用前景。本文概述了杂多酸的质子导电性,归纳了其质子导电性的一些规律,以表格形式列举了各类杂多酸的电导率。将不同质量分数的杂多酸固载在各类固体基质上,可以对杂多酸质子导电材料改性以便于工业中实际应用。这些杂化材料兼有杂多酸的高质子导电性以及基质的稳定性与机械延展性。本文综述了近几年来新型杂多酸,杂多酸-无机基质复合材料,杂多酸-有机基质复合材料,杂多酸-多元基复合材料的质子电导率、稳定性、结构形态等等方面的研究进展,详细介绍了杂多酸在质子交换膜燃料电池中的应用,并对杂多酸固体高质子导体的应用前景进行了展望。     

燃料电池用跨温区质子交换膜材料研究进展

质子交换膜燃料电池(PEMFC)是一种电化学能量转换器件，能将燃料中的化学能转换为电能，具有高效、清洁、寿命长等优点，可应用于动力电池、固定式和便携式电源等领域。质子交换膜(PEM)是其中的关键部件，主要用于隔离阴阳两极和传递质子等。但当前质子交换膜燃料电池的发展面临着成本高、寿命不足等挑战。本文结合近年的研究热点，从质子传输机制出发将质子交换膜燃料电池分为磺酸功能化PEM和磷酸掺杂型PEM两大类，从主链结构的差异以及改性方法等方面综述近年来的研究进展，详细介绍了材料的化学结构、膜材料性能、电化学性能等，并针对现存的一些问题和不足对质子交换膜燃料电池今后的发展方向进行了展望。     

交联聚离子液体的合成及质子传导性能研究

本文设计合成了四种具有超高质子传导性能的交联聚离子液体材料。采用红外、元素分析、X射线光电子能谱和扫描电镜等表征手段对所合成材料的化学组成及结构进行了解析;采用热分析技术对材料的热稳定性进行了研究;系统研究了在不同条件下所合成材料的质子传导性能。研究结果表明:所合成的系列聚离子液体材料具有交联的三维结构;优异的热稳定性,其分解温度均超过253℃,最高分解温度可达314℃。在80℃和98%相对湿度(RH)下,这些材料的最大质子电导率为1.89×10~(-2) S·m~(-1)。该类聚离子液体材料超高的质子传导性能和简易的合成工艺,为新型质子传导材料的发展提供了新的思路。     

新颖无机质子传导材料的研究进展

质子传导在燃料电池、气体传感及电致显色等领域有重要的研究前景.尤其是在燃料电池领域,由于其具有低污染、高效率、操作简单和寿命长等优点而被广泛应用.本文介绍了质子传导在质子交换膜燃料电池中的重要作用及工作原理,分析了质子交换膜的质子传导机理,并简要分析总结了近年来关于无机及其复合质子导体材料的研究进展.     

基于膦酸基的高温质子交换膜的研究进展

提高质子交换膜燃料电池(PEMFCs)的工作温度,不但可以提高电催化剂的活性以及电催化剂对原料气中CO等杂质气体的耐受能力,少用甚至不用Pt等贵金属作电催化剂,还可以简化PEMFCs的水热管理系统,提高PEMFCs的综合能量转化效率.实现高温PEMFCs的核心是开发能够适用于高温PEMFCs的高温质子交换膜(HT-PEM),是PEMFCs的研究热点.在众多HT-PEM候选材料中,基于膦酸基的质子交换膜材料是最具前途的候选材料之一,是制备HT-PEM的主要研究方向.本文综述了基于膦酸基的HT-PEM的研究进展,讨论了膦酸基参与的质子传导机理,比较了纯聚合物膦酸膜、膦酸基接枝改性膜、酸-碱两性膜、掺杂型复合膜的电导率、物理化学稳定性、机械性能等.最后,展望了基于膦酸基的HT-PEM的发展趋势.     

基于膦酸基的高温质子交换膜的研究进展

提高质子交换膜燃料电池(PEMFCs)的工作温度,不但可以提高电催化剂的活性以及电催化剂对原料气中CO等杂质气体的耐受能力,少用甚至不用Pt 等贵金属作电催化剂,还可以简化PEMFCs的水热管理系统,提高PEMFCs的综合能量转化效率. 实现高温PEMFCs的核心是开发能够适用于高温PEMFCs的高温质子交换膜(HT-PEM),是PEMFCs的研究热点. 在众多HT-PEM候选材料中,基于膦酸基的质子交换膜材料是最具前途的候选材料之一,是制备HT-PEM的主要研究方向. 本文综述了基于膦酸基的HT-PEM的研究进展,讨论了膦酸基参与的质子传导机理,比较了纯聚合物膦酸膜、膦酸基接枝改性膜、酸-碱两性膜、掺杂型复合膜的电导率、物理化学稳定性、机械性能等. 最后,展望了基于膦酸基的HT-PEM的发展趋势.     

燃料电池质子交换膜研究进展与展望

质子交换膜燃料电池(PEMFC)作为一种清洁高效的能量转换装置,具有比功率高、稳定性好、易于启动等优点,是未来可移动动力源的理想候选。成本和寿命是阻碍PEMFC商业化的主要原因,寻找新型材料是解决这两大问题的必然选择,也是近年来质子交换膜研究的热点和重点。本文介绍了几种质子交换膜材料的研究进展,主要包括聚合物型、陶瓷型和有机-无机复合型,讨论了各种膜材料的特点,并对其未来的发展加以展望。     

含有POSS的复合型质子交换膜的制备及性能

本文以一种具有含萘结构的磺酸化聚芳醚酮作为主体材料, 采用具有相似化学结构的含萘、 醚和酮结构的聚甲亚胺作为增强组分, 通过溶胶-凝胶的方法在复合膜中引入提高质子传输能力的酸功能化聚倍半硅氧烷(POSS-SO3H), 制备新型的三元复合型质子交换膜, 并对其微结构和性能进行了研究.     

新型均二苯乙烯化合物的合成及其荧光特性

有机共轭化合物作为光电发光材料,已经呈现出诱人的应用前景[1-3]。而设计合成红、绿和蓝三色发光性稳定且有效的有机共轭发光材料是制造彩色有机发光器件(OLED)的基本条件。类似均二苯乙烯型的发射蓝光的有机共轭化合物通常都具有较大的禁带宽度,空穴和电子两种载流子双极平衡注入效率低,发光强度和发光效率不尽人意。因此,近年来各国学者都积极在改进均二苯乙烯类发光材料性能方面进行了系列研究,许多研究结果表明三苯胺基和噁二唑环分别是此类发光材料的良好的空穴传输基团和电子传输基团[4-7],所以有理由相信:同时将三苯胺基和1,3,4-…     

Two‐in‐One: Inherent Anhydrous and Water‐Assisted High Proton Conduction in a 3D Metal–Organic Framework

The development of solid‐state proton‐conducting materials with high conductivity that operate under both anhydrous and humidified conditions is currently of great interest in fuel‐cell technology. A 3D metal–organic framework (MOF) with acid–base pairs in its coordination space that efficiently conducts protons under both anhydrous and humid conditions has now been developed. The anhydrous proton conductivity for this MOF is among the highest values that have been reported for MOF materials, whereas its water‐assisted proton conductivity is comparable to that of the organic polymer Nafion, which is currently used for practical applications. Unlike other MOFs, which conduct protons either under anhydrous or humid conditions, this compound should represent a considerable advance in the development of efficient solid‐state proton‐conducting materials that work under both anhydrous and humid conditions.     

燃料电池用聚合物质子交换膜的研究进展

质子交换膜（PEM）是质子交换膜燃料电池的核心组件之一,具有隔绝阴阳极、提供质子传递通道和阻止燃料渗透的作用. 商业化应用的全氟磺酸PEM存在燃料渗透严重、高温条件下导电性差和成本高的问题,开发性能优良的聚合物PEM显得很有必要. 本文讨论了近年来聚合物PEM的研究进展,分别从聚合物的主链、支链和交联结构角度介绍了分子结构对薄膜相分离、质子导电性、稳定性和电池性能等性能的影响,并讨论了聚合物分子结构设计方面存在的问题,最后对燃料电池用聚合物PEM在未来的发展方向进行了展望.     

2-取代咪唑衍生物掺杂高温非水用Nafion质子交换膜的制备和性能

高温质子交换膜燃料电池所面临的一个主要技术障碍是高温低湿度环境下能够具有满足电池工作条件的膜的制备.本文通过所合成的2-取代咪唑衍生物与全氟磺酸树脂的掺杂,采用溶液重铸法制备了可以在高温无水条件下工作的质子交换膜.通过2-位疏水基团的接枝,实现了非水质子传导介质的咪唑环在膜内的固定,所制备的复合质子交换膜的导质子率在160℃无水条件下达到6.8×10^-3Scm^-1;而且相比全氟磺酸均质膜,其热稳定性也有所提高.采用静电力显微镜观察到了所制备的复合质子交换膜内相互连接的离子团簇的形成;结合其质子传导活化能,提出了所制备的复合质子交换膜在120℃以下质子传导以跳跃方式为主;在120℃以上,则以咪唑环的＂钟摆＂形式实现质子在膜内的传输.     

The effect of octahedral tilting on proton binding sites and transition states in pseudo-cubic perovskite oxides

Proton conducting oxide ceramics have shown potential for use in fuel cell technologies. Understanding the energy pathways for proton conduction could help us design more efficient fuel cell materials. This paper describes how octahedral tilting affects the relative energies of proton binding sites, transition states, and conduction pathways in cubic and pseudo-cubic perovskites. First, the structure for cubic and pseudo-cubic forms of BaTiO(3), BaZrO(3), CaTiO(3), and CaZrO(3), is found. Even when cubic symmetry is enforced, CaTiO(3), and CaZrO(3) exhibit octahedral tilting distortions characteristic of orthorhombic phases while BaTiO(3) and BaZrO(3) remain undistorted. Octahedral tilting gives rise to proton binding sites facilitating inter- and intra-octahedral proton transfer while the proton binding sites of undistorted perovskites facilitate only intra-octahedral proton transfer. The nudged elastic band method is used to find minimum energy paths between the proton binding sites. As distortions increase, inter-octahedral proton transfer barriers decrease while intra-octahedral proton transfer barriers increase. Concurrently, rotational barriers from oxygens facilitating inter-octahedral proton transfer increase while rotational barriers from oxygens facilitating intra-octahedral proton transfer decrease. Intra-octahedral transfer is the rate-limiting step to the lowest energy extended proton conduction pathway in all the perovskites considered.     

Combined Intrinsic and Extrinsic Proton Conduction in Robust Covalent Organic Frameworks for Hydrogen Fuel Cell Applications

Developing new materials for the fabrication of proton exchange membranes (PEMs) for fuel cells is of great significance. Herein, a series of highly crystalline, porous, and stable new covalent organic frameworks (COFs) have been developed by a stepwise synthesis strategy. The synthesized COFs exhibit high hydrophilicity and excellent stability in strong acid or base (e.g., 12 m NaOH or HCl) and boiling water. These features make them ideal platforms for proton conduction applications. Upon loading with H₃PO₄, the COFs (H₃PO₄@COFs) realize an ultrahigh proton conductivity of 1.13×10^?1 S cm^?1, the highest among all COF materials, and maintain high proton conductivity across a wide relative humidity (40–100 %) and temperature range (20–80 °C). Furthermore, membrane electrode assemblies were fabricated using H₃PO₄@COFs as the solid electrolyte membrane for proton exchange resulting in a maximum power density of 81 mW cm^?2 and a maximum current density of 456 mA cm^?2, which exceeds all previously reported COF materials.     

Hydrogen‐Bonded Organic Frameworks (HOFs): A New Class of Porous Crystalline Proton‐Conducting Materials

Two porous hydrogen‐bonded organic frameworks (HOFs) based on arene sulfonates and guanidinium ions are reported. As a result of the presence of ionic backbones appended with protonic source, the compounds exhibit ultra‐high proton conduction values (σ) 0.75× 10^?2 S cm^?1 and 1.8×10^?2 S cm^?1 under humidified conditions. Also, they have very low activation energy values and the highest proton conductivity at ambient conditions (low humidity and at moderate temperature) among porous crystalline materials, such as metal–organic frameworks (MOFs) and covalent organic frameworks (COFs). These values are not only comparable to the conventionally used proton exchange membranes, such as Nafion used in fuel cell technologies, but is also the highest value reported in organic‐based porous architectures. Notably, this report inaugurates the usage of crystalline hydrogen‐bonded porous organic frameworks as solid‐state proton conducting materials.     

Proton conductivity of membranes based on the sulfocationites MSC-H and purolite CT-275

The proton conductivity properties of new heterogeneous membranes based on the sulfocationites MSC-H and Purolite CT-275, which are stable in polar media, have been studied. The specific proton conductivity of the membranes were (1–2.3)·10⁻⁴ S/cm at 75–95 °C. The value of the proton conductivity is determined by the exchange capacity of the membranes and the structure of the hydration shell of the transported proton. The latter depends on the temperature, the relative humidity, and the current intensity through the membrane. __________ Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 1, pp. 52–57, January–February, 2007.     

Proton conductivity in crosslinked hydrophilic ionic polymer system: Competitive hydration,crosslink heterogeneity,and ineffective domains

High proton conductivity in hydrophobic backbone‐based polymers such as Nafion is known to be due to the formation of organized ionic clusters and channels upon hydration. However, a lower proton conductivity in hydrophilic, ionic polymers and the role played by the microstructure are not well understood. In this work, we demonstrate the importance of heterogeneity in crosslinked ionic polymer networks in explaining proton conductivity. Poly(vinyl alcohol) (PVA) crosslinked with sulfosuccinic acid (SSA) is used as the model polymer system for the study. Evolution of the microstructure with hydration and the effect on proton conductivity are analyzed using ATR‐FTIR spectroscopy, dielectric spectroscopy, and small‐angle neutron scattering. We show that the presence of the two hydrophilic groups in PVA‐SSA (hydroxyl and sulfonic acid), as opposed to Nafion, results in competition for water and a lower proton conductivity. The crosslinked polymer–water system contains heterogeneous domains of crosslink nodes which are conductive. These domains (of size 20–35 Å) interconnect with each other and form tortuous percolating domains through which proton conduction takes place. The presence of hydroxyl groups results in some of the domains being ineffective for proton transport, resulting in a lower conductivity. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1087–1101     

含羧基交联型质子交换膜的制备及其性能

合成了一种含酯基的磺化聚合物,利用后水解的方法得到了含有羧基侧基的聚合物;将磺化聚合物与聚乙烯醇通过溶液共混,热处理后得到交联型的共混膜材料。 研究结果表明,膜材料的玻璃化转变温度(Tg)有明显的上升,证明了交联反应的发生;同时,膜的吸水率和溶胀率有一定的下降,力学性能和热稳定性也有一定的提升。 通过共价交联的方法,制备了综合性能优异的磺化聚芳醚质子交换膜材料。 在100 ℃,交联膜的质子传导率为0.072~0.065 S/cm,吸水率为51%~89%,溶胀率为19%~30%。