质子交换膜燃料电池关键技术研究进展

简述了质子交换膜燃料电池(PEMFC)的工作原理及特点;综述了PEMFC关键技术的最新研究进展,包括质子交换膜合成、电催化剂制备、膜电极工艺及水管理和热控制;并简介了我国PEMFC的开发情况。     

高温质子交换膜研究进展

高温质子交换膜燃料电池解决了传统质子交换膜燃料电池催化剂易受CO等杂质气体毒化、水热管理复杂等问题,成为当今燃料电池发展的主要方向。高温质子交换膜是实现高温操作的关键部分。本文结合质子传递机理,分析了以水作为质子溶剂、非水质子溶剂质子交换膜以及无机固态质子导体膜的研究现状,认为有机/无机复合膜和非水质子溶剂膜,尤其是其中的磷酸掺杂的PBI膜是高温质子交换膜的发展方向。     

高温质子交换膜研究进展

高温质子交换膜燃料电池（HT-PEMFCs）因其具有催化剂CO耐受性良好,能量转化率高,水热管理简单等优点,成为了能源领域重要的研究方向之一。高温质子交换膜（HTPEM）是它的主要部件之一,分别以水、磷酸分子和咪唑分子为质子传导载体分析了目前HTPEM的研究现状,比较后得出了以磷酸为质子载体的HTPEM性能最佳的结论,指出了研究中尚存的问题,并展望了未来HTPEM可能的研究方向。     

质子交换膜燃料电池研究进展

由于质子交换膜燃料电池（PEMFC）具有能量转化效率高、寿命长、比功率和比能量高、以及对环境友好等优点,近年来得到迅速发展.笔者综述了PEMFC的特点,分析了PEMFC在国内外的最新研究进展,介绍了PEMFC的应用前景,并指出了PEMFC研究当前需要解决的技术问题及其发展趋势.     

燃料电池质子交换膜研究进展

质子交换膜作为燃料电池的关键材料之一,得到世界各国学者的广泛关注和深入研究,已先后研发出含氟高分子类、芳香烃聚合物类以及有机/无机杂化材料的质子交换膜.本文对燃料电池工作原理进行简要概述,并针对质子交换膜的应用前景及研究现状进行分析.     

质子交换膜燃料电池的研究进展

质子交换膜燃料电池（PEMFC）是一种高效节能、工作稳定、环境友好的理想发电装置。质子交换膜是PEMFC的核心组成,是一种选择透过性膜,主要起传导质子、分割氧化剂与还原剂的作用。PEMFC用电催化剂主要为铂系电催化剂,为降低成本,提高铂的利用率和开发非铂系催化剂是今后催化剂研究的主要方向之一。对PEMFC电极的工作原理,关键组件及电池的水管理、热管理方法等作了综述。     

燃料电池用质子交换膜的研究进展

介绍了三类质子交换膜,包括全氟磺酸膜、磺化聚芳烃系列膜和复合型质子交换膜,主要分析了每种膜的优缺点以及在质子交换膜燃料电池(PEMFC)中的应用前景.     

用于质子交换膜的高质子传导率聚合物研究进展

质子传导率超过Nafion膜的质子交换膜是近年来研究的焦点。质子交换膜的质子传导率与它们的IEC值和形态有关。形成离子通道是开发高质子传导率的质子交换膜的一种有效方法。形成离子通道主要有3种:1)用嵌段共聚物的微相分离;2)侧链和支链磺化的聚合物;3)局部区域的高密集磺化。此外,与无机纳米材料形成纳米复合材料的质子交换膜也能提高质子交换膜的质子传导率及质子交换膜的机械强度、尺寸稳定性、耐氧化稳定性等性能。综述了关于用于高质子传导率的燃料电池质子交换膜(PEM)的聚合物的研究进展。对高质子传导率的燃料电池膜聚合物的发展趋势进行了展望。     

聚砜类燃料电池质子交换膜研究进展

介绍了质子交换膜的分类,综述了主链型聚砜质子交换膜、侧链型聚砜质子交换膜、无机掺杂复合型聚砜质子交换膜等聚砜类燃料电池质子交换膜的最新研究进展,全面阐述了磺化聚砜的形貌、结构对材料物理化学性能的影响,并展望了聚砜类燃料电池质子交换膜的发展前景。     

质子交换膜燃料电池研究进展

介绍了燃料电池的工作原理及目前世界上主要燃料电池的主要特性;综述了质子交换膜燃料电池(PEMFC)的主要基础研究进展;简单介绍了PEMFC关键部件的研究方向。     

Sulfonated polyimides bearing benzimidazole groups for proton exchange membranes

A series of sulfonated polyimides containing benzimidazole groups were synthesized using 4,4′-binaphthyl-1,1′,8,8′-tetracarboxylic dianhydride (BTDA), 4,4′-diaminodiphenyl ether-2,2′-disulfonic acid (ODADS) as the sulfonated diamine, and 2-(3′,5′-diaminophenyl)benzimidazole (a) or 6,4′-diamino-2-phenylbenzimidazole (b) as the nonsulfonated diamine. The electrolyte properties of the synthesized polyimides (Ia − x, Ib − x, x refers to molar percentage of the sulfonated diamine) were investigated and compared with those of polyimides (Ic − x) from BTDA, ODADS, and m-phenylenediamine (c). All synthesized polyimides possessed high molecular weights revealed by their high viscosity, and formation of tough and flexible membranes. Polyimides with benzimidazole groups exhibited much better swelling capacity than those without benzimidazole groups. This was attributed to the strong interchain interaction through basic benzimidazole functions and sulfonic acid groups. The sulfonated polyimides that are incorporated with 1,1′,8,8′-binaphthalimide exhibited better hydrolytic stability than that with 1,4,5,8-naphthalimide. Polyimide membranes with good water stability as well as high proton conductivity were developed. Polyimide membrane (Ia − 90), for example, did not lose mechanical properties after being soaked in boiling water for 1000 h, while its proton conductivity was still at a high level (compared to that of Nafion 117).     

Sulfonated poly(ether ether ketone) membranes crosslinked with sulfonic acid containing benzoxazine monomer as proton exchange membranes

The incorporation of benzoxazine (Ba) or sulfonic acid containing benzoxazine (SBa) as a crosslinking agent in SPEEK proton exchange membrane (PEM) can substantially improve the SPEEK membrane performance. The SPEEK-SBa membranes give higher effective selectivity than corresponding SPEEK-Ba membranes under close crosslinker loading and thus are more suitable to be used in direct methanol fuel cells. The best achieved SPEEK-SBa composition (SBa40) gives reasonable proton conductivity (0.91 × 10⁻² S cm⁻¹) but significantly lower methanol permeability (6.5 × 10⁻⁸ S² cm⁻¹). The achieved effective selectivity (Φ = SPEEK-SBa40: 14.0 × 10⁴ S s cm⁻³) is substantially higher than the plain SPEEK (Φ = 7.24 × 10⁴ S s cm⁻³) which has great potential for practical applications in DMFCs.     

Preparation of proton exchange membranes based on crosslinked polytetrafluoroethylene for fuel cell applications

We prepared proton exchange membranes by the γ-ray-induced post grafting of styrene into crosslinked polytetrafluoroethylene (PTFE) films and subsequent sulfonation. The degree of grafting was controlled in the range of 7-75% by the crosslinking density of the PTFE matrix as well as the grafting conditions. Under our preparation conditions, the films at the grafting yield of ≥30% were found to produce ion exchange membranes with a homogeneous distribution of sulfonic acid groups. The resulting membranes showed a large ion exchange capacity up to 2.9 meq g⁻¹, which exceeded the performance of commercially available perfluorosulfonic acid films such as Nafion; nevertheless, they appeared to be dimensionally stable in water. These should undoubtedly result from the use of the crosslinked PTFE films as graft substrates and make our ion exchange membranes promising for applications to polymer electrolyte fuel cells.     

Sulfonated aromatic hydrocarbon polymers as proton exchange membranes for fuel cells

This article reviews recent studies on proton exchange membrane (PEM) materials for polymer electrolyte fuel cells. In particular, it focuses on the development of novel sulfonated aromatic hydrocarbon polymers for PEMs as alternatives to conventional perfluorinated polymers. It is necessary to improve proton conductivity especially under low-humidity conditions at high operating temperatures to breakthrough the current aromatic PEM system. Capable strategies involve the formation of well-connected proton channels by microphase separation between hydrophilic and hydrophobic domains and the increase of the ion exchange capacity of PEMs while keeping water resistance. Herein, we introduce novel molecular designs of sulfonated aromatic hydrocarbon polymers and their performance as PEMs.     

Electro-osmotic drag of methanol in proton exchange membranes

A good understanding of the fundamental transport phenomena of water and methanol in PSA (Perfluoro Sulfonic Acid) membranes is one of the keys in developing efficient direct methanol fuel cells (DMFCs). Electro-osmosis, being one of the most important water and methanol transport mechanisms in DMFCs, has been investigated with a number of different proton exchange membranes. Two aspects were of particular interest: firstly, the interdependencies between the electro-osmotic drag coefficient and methanol concentration and temperature, and secondly the interdependence between the electro-osmotic drag coefficient and current density. The results of these investigations are compared to published data.     

Hydration behavior of perfluorinated and hydrocarbon-type proton exchange membranes: Relationship between morphology and proton conduction

The relationships between morphology and proton conduction for Nafion membranes and hydrocarbon-type proton exchange membranes, namely, sulfonated poly(arylene ether ether ketone) (S-PEEK) and sulfonated poly(arylene ether sulfone) (S-PES), were investigated by small-angle X-ray scattering (SAXS) and atomic force microscopy (AFM). The direct simultaneous observation of surface morphology and active regions of proton conduction on membranes by combined high-resolution AFM phase imaging and an electrochemical technique at controlled humidity provided significant morphological information, particularly for the hydrocarbon-type membranes that exhibit few or no features on SAXS profiles. For the Nafion membranes, the active proton paths became denser and congregated with each other at over 60% RH, resulting in the formation of well-connected networks. For the hydrocarbon-type membranes, however, only the relatively small and dispersed proton paths were observed, which showed no significant change even as water content increased. We have demonstrated that the differences in microscopic morphology between the Nafion and hydrocarbon-type membranes are associated with the differences between their macroscopic proton conductivities.     

Novel side-chain-type sulfonated hydroxynaphthalene-based Poly(aryl ether ketone) with H-bonded for proton exchange membranes

A series of novel side-chain-type sulfonated hydroxynaphthalene poly(aryl ether ketone)s (SHNPAEKs) containing hydroxyl groups was synthesized by post grafted method and the sulfonated degree (Ds) of the polymers could be well controlled. The resulting polymers were characterized by ¹H NMR, FT-IR and thermogravimetric analysis (TGA). Meanwhile, the membrane properties for fuel cell applications such as water uptake, proton conductivity and methanol transport have been studied. The influence of pendent structure and inter-/intramolecular H-bonded to the properties of SHNPAEKs has been investigated. The proton conductivities of SHNPAEK membranes showed a range of 0.020-0.197 S/cm and the highest conductivity of 0.197 S/cm was obtained for SHNPAEK-90 (IEC = 2.08 meq./g) at 80 °C. The methanol permeability of SHNPAEK membranes was in the range from 2.65 × 10⁻⁷ to 11.9 × 10⁻⁷ cm²/s, which was much lower than that of Nafion 117.     

Synthesis of sulfonated poly(arylene-co-naphthalimide)s as novel polymers for proton exchange membranes

A series of novel sulfonated poly(arylene-co-binaphthalimide)s (SPPIs) were successfully synthesized via Ni(0) catalytic coupling of sodium 3-(2,5-dichlorobenzoyl)benzenesulfonate and bis(chloronaphthalimide)s. Bis(chloronaphthalimide)s were conveniently prepared from 5-chloro-1,8-naphthalic anhydride and various diamines. Tough and transparent SPPI membranes were prepared and the electrolyte properties of the copolymers were intensively investigated as were the effects of different diamine structures on the copolymer characterisitics. The copolymer membrane Ia-80, with an ion exchange capacity (IEC) of 2.50 meq g⁻¹, displayed a higher proton conductivity, i.e. 0.135 S cm⁻¹ at 20 °C, as compared to Nafion 117 (0.09 S cm⁻¹, 20 °C). The copolymer membrane Id-70, containing 3,3′-dimethyl-4,4′-methylenedianiline (DMMDA) units, exhibited excellent stability toward water and oxidation due to the introduction of hydrophobic methyl groups on the ortho-position of the imido bond in the copolymer. The mechanical property of Id-70 remained virtually unchanged after immersing membrane in pressured water at 140 °C for 24 h. Furthermore, the introduction of aliphatic segment a hexane-1,6-diamine (HDA) in copolymer led to a significant increase in proton conductivity and water uptake with increasing temperature; the proton conductivity of the Ic-70 membrane reached 0.212 S cm⁻¹ at 80 °C, which was higher than Nafion 117 as well as of the membranes based on aromatic diamines at equivalent IEC values. Consequently, these materials proved to be promising as proton exchange membranes.     

Structures and properties of highly sulfonated poly(arylenethioethersulfone)s as proton exchange membranes

A series of sulfonated poly(sulfonium cation) polymers, sulfonated poly(arylenethioethersulfone)s (SPTES)s possess up to two sulfonate groups per repeat unit, and can be easily converted into corresponding acid form of the SPTES polymer to form a tough, ductile, free-standing, pinhole-free membranes with excellent mechanical properties. The SPTES polymers exhibit good water affinity and excellent proton conductivity due to the high water uptake. Proton conductivities between 100 and 300 mS/cm (at 65 °C, 85% relative humidity) were observed for the SPTES polymers with 50 mol% (SPTES-50) to 100 mol% (SPTES-100) of sulfonated monomer. The evaluation by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermomechanical analysis (TMA) showed that the SPTES polymers have excellent thermal stability, mechanical properties, and dimensional stability, making them excellent candidates for the next generation of proton exchange membranes (PEMs) in fuel cell applications.     

Methods for modifying proton exchange membranes using the sol-gel process

Over the past 20 years, sol-gel processing has expanded into organic-inorganic hybrid materials. This expansion has benefited from the collaborations between the polymers community and the ceramics community, and the discovery that in many instances sol-gel processing and polymer processing are compatible. An active participant in this field has been Dr James E. Mark [Mark JE. Heterog Chem Rev 1996;3:307-320], and his accomplishments deserve this tribute. One example, which derives from his work in organically-modified silicates (ORMOSILS), is hybrid membranes for fuel cells. We present some recent progress in synthesis of hybrid membranes involving Nafion. These membranes have been prepared by infiltration and recasting, and contain silicates, phosphosilicates, zirconium phosphosilicates and titanosilicates.