季铵盐化氧化石墨烯复合磺化聚磷腈质子交换膜的制备与表征

制备了一系列含有季铵盐化氧化石墨烯(QGO)的磺化聚磷腈类复合质子交换膜。通过对复合膜的稳定性能和电化学性能测试发现,复合膜(SP-x-QGO)的吸水率和溶胀度都低于纯磺化聚磷腈膜(SPFPP)。复合膜具有较好的抗氧化性能;复合膜SP-3-QGO在80℃完全吸水条件下的质子传导率为0.092 S/cm。结果表明,季铵盐化的氧化石墨烯(QGO)复合磺化聚磷腈类质子交换膜(SP-x-QGO)在燃料电池领域具有很大的发展前景。     

燃料电池用聚乙烯基质子交换膜研究进展

简介了燃料电池的重要性及质子交换膜在燃料电池中的核心地位。简述了目前燃料电池用质子交换膜研究中，设计具有成本低、加工性好、燃料选择性好等优点的质子交换膜替代全氟磺酸膜的发展趋势，分析了聚乙烯基质子交换膜的优势，介绍了近年来聚乙烯基质子交换膜的制备方法和基本性能，指出可通过聚乙烯与磺化聚合物共混、设计合成磺化聚乙烯以及聚乙烯-磺化聚合物接枝共聚物等3种方法制备聚乙烯基质子交换膜。最后提出设计合成具有电导率高、燃料阻隔性好、成本低、加工性好、温度和湿度稳定性好的不同结构的聚乙烯基质子交换膜以及开发其高效合成方法是未来的重点研发方向。     

磺化聚磷腈类质子交换膜研究进展

保护环境,开发环保型能源,对人类和社会具有重要意义。质子交换膜燃料电池由于环境友好,近年来引起了电池领域研究者们的兴趣。质子交换膜是燃料电池的重要组成部分,磺化聚磷腈由于具有质子传导率高,稳定性能好,成本较低等优点可以作为质子交换膜的备选材料。本文主要综述了磺化聚磷腈类质子交换膜在燃料电池质子交换膜方面的研究进展,详细介绍了此类质子交换膜的制备和表征,同时对其应用前景做了评论和展望。     

高温质子交换膜燃料电池用离子液体聚合物电解质的研究进展

综述了近十几年来高温质子交换膜燃料电池用离子液体聚合物电解质的研究进展及其在高温质子交换膜燃料电池中的应用进展,指出了此类电解质目前存在的亟待解决的两个问题：咪唑类离子液体毒化Pt基催化剂和复合膜中离子液体的长期稳定性。最后对高温质子交换膜燃料电池用离子液体聚合物电解质的发展前景作了展望,即开发与Pt基催化剂相容的离子液体聚合物电解质以及预防复合膜内离子液体的流失,即提高高温质子交换膜燃料电池的性能及长期稳定性,最终提高高温燃料电池的寿命。     

用于燃料电池的聚合物电解质膜及其改性方法

聚合物电解质膜是质子交换膜燃料电池的核心部件.目前广泛使用的全氟质子交换膜(如Nafion(R)系列)存在着价格昂贵、使用温度有限、甲醇渗透率高以及降解再生困难等缺点.对聚合物基质材料进行物理或化学改性,可以提高质子传导率、改善机械强度等性能,获得高性能、低成本的质子交换膜.从聚合物材料改性的角度,综述了燃料电池用聚合物电解质膜的制备方法和电化学性能,并对各种改性方法进行了比较.     

燃料电池高温质子交换膜研究进展

高温质子交换膜燃料电池具有反应动力学快、CO耐受性高等特点,但磷酸掺杂的高温质子交换膜因磷酸的流失和聚合物的降解等原因导致燃料电池的输出功率发生衰减。本文通过介绍聚苯并咪唑衍生物的高温质子交换膜、聚苯并咪唑的复合型质子交换膜、新型芳基聚合物的高温质子交换膜,阐明聚合物的主链结构、官能团结构以及复合填料对高温质子交换膜性能的影响。在近期的研究报道中,提高膜性能的主要策略包括提升自由体积、建立交联结构、嵌段共聚、复合掺杂（ILs、MOFs、PIMs、MO_x）、阳离子官能团修饰等。文章指出,在未来的研究中应该加强对磷酸基高温质子交换膜质子传输通道结构的进一步理解,关注聚合物化学降解和物理性能衰败的原因,并开发更多的新型聚合物材料。     

新型燃料电池复合膜

被认为最有可能用于未来的非散热式交通工具的燃料电池是质子交换膜燃料电池。当前这种质子交换膜燃料电池能够在60—80℃温度范围内工作，遗憾的是，当前这种燃料电池由于含有大约10mg／L一氧化碳而容易使人中毒。目前美国普林斯顿大学的化学家Andrew B．Bocarsly和他的同事正在寻找解决该问题的方法，他们发现这种燃料电池在120—150℃工作时可以克服该问题．但在该温度范围内处于燃料电池中心的质子传导聚合物膜很难保留水分．水的保留决定其性能的优劣。Bocarsly的解决方案是利用经过改性并含有像二氧化钛之类金属氧化物粒子的膜来帮忙保留水分。该研究小组说，如果安装这种复合膜，燃料电池在130℃下比80℃下工作得好．而且在氢燃料中含有500mg／L的一氧化碳也不碍事。     

氮杂环离子液体及其衍生物在高温质子交换膜中的应用研究进展

回顾了近年来氮杂环类离子液体作为离子传导介质在高温质子交换膜中的应用,主要体现在直接物理掺杂、高分子主链修饰改性、采用无机有机复合技术在膜内锚固3个方向。采用离子液体与聚合物电解质直接掺杂所制备的质子交换膜在高温条件下表现出了优异的质子传导性能,但离子液体容易随电极反应生成的水而流失,进而造成电池性能下降的缺点限制了其实际应用;采用离子液体单元对高分子主链进行修饰可以实现离子液体在质子交换膜内的固定,而复杂的合成工艺以及离子液体单元的低柔顺性导致的低电导率是其存在的缺点;通过离子液体修饰的无机纳米氧化物与聚合物电解质的掺杂也可以实现离子液体在质子交换膜中的固定,这类膜材料的制备难点在于连续质子传导相的形成以及提高离子液体单元的可移动性。在对上述3个主要研究方向的特点进行概括和评述的基础上,指出通过有机无机复合技术实现离子液体在质子交换膜内的固定并提高离子液体的局部柔顺性是未来高温质子交换膜的重点研究方向。     

燃料电池用质子交换膜

介绍了燃料电池用含氟质子交换膜的研究历程、应用、结构与性能的关系及当前针对性的改进,归纳了磺化碳氢聚合物、有机无机复合物、离子交联聚合物和无机固体酸等非氟质子交换膜的代表性研究,指出了各利非氟质子交换膜的优点和不足,对质子交换膜的发展做了相应的展望。     

细菌纤维素在电池应用中的研究进展

介绍了细菌纤维素的特点,阐述了细菌纤维素在电池应用中的进展,重点叙述了细菌纤维素在锂离子电池隔膜、燃料电池质子交换膜以及液流电池离子交换膜等方面的应用研究。尤其是细菌纤维素/无机物复合以及细菌纤维素/有机聚合物复合,以制备电池用纳米复合膜的相关研究。同时介绍了复合中应用到的工艺,包括原位复合法、溶胶凝胶法等。最后,对细菌纤维素在电池方面的研究工作进行了总结,评价了其作为电池隔膜的优缺点,并对其应用前景做了展望。     

Enhanced transport properties in polymer electrolyte composite membranes with graphene oxide sheets

Polymer electrolyte membranes have been widely investigated for high performance fuel cells. Here, we report the synthesis of ionic conductive Nafion/graphene oxide (GO) composite membranes for application in direct methanol fuel cells. GOs interact with both the non-polar backbone and the polar ionic clusters of Nafion because of their amphiphilic characteristics attributable to hydrophobic conjugation and hydrophilic functional groups. Accordingly, GO sheets serve to modify the microstructures of two domains of Nafion. In particular, the transport properties of Nafion are favorably manipulated by the incorporation of GO. This modulated the ionic channels of Nafion and decrease methanol crossover while preserving ionic conductivity. Furthermore, strong interfacial interactions due to the insertion of GO nanofillers into the Nafion matrix improve the thermal and mechanical properties of the material. In particular, we exploit Nafion/GO composite membrane as electrolyte material for direct methanol fuel cell (DMFC) in order to resolve current issue of methanol crossover. This composite membrane-based DMFC compared to the Nafion 112-based DMFC remarkably enhanced cell performance, especially in severe operating conditions.     

磺化含酚酞侧基聚芳醚酮/氧化石墨烯复合质子交换膜的性能

采用共混制备了一系列磺化含酚酞侧基聚芳醚酮(SPEK-C)/氧化石墨烯(GO)复合质子交换膜,系统地研究了GO含量对复合膜性能的影响。结果表明,GO含量对膜的离子交换容量、稳定性、质子电导率和甲醇渗透率等有重要影响。复合膜质子电导率随GO含量增加而提高,GO含量为2%和5%的复合膜在80℃下质子电导率均在10^-1 S·cm^-1以上。80℃下,GO含量为5%的复合膜甲醇渗透率为6.69×10^-7 cm²·s^-1,低于同温度下复合前SPEK-C膜1个数量级。复合后膜的化学稳定性增强,离子交换容量和含水率均有提高,相对选择性明显增大,最高达SPEK-C的18.2倍。     

燃料电池用纳米改性聚苯并咪唑阴离子交换膜的制备

以环氧氯丙烷和1–甲基咪唑为原料制备新型离子液体(IL),以IL为原料对氧化石墨烯(GO)进行表面修饰制备离子液体功能化氧化石墨烯(IL–GO),以IL–GO为添加剂制备基于含氟聚苯并咪唑(FPBI)复合膜。研究了IL–GO的含量对复合膜的热稳定性、力学强度、离子电导率、离子交换容量(IEC)、吸水率、溶胀度和耐碱性等性能的影响。研究结果表明,复合膜的IEC、离子电导率和拉伸性能都随着IL–GO含量的增加而增大,当IL–GO含量为30%时其拉伸应力和拉伸弹性模量分别达到77.5 MPa和1.95 GPa,在80℃下,其最大离子电导率可达72.3 m S/cm,然而复合膜的热稳定性并没随着IL–GO含量的增加而改变。FPBI/IL–GO复合膜具有良好的稳定性,该系列阴离子交换膜有望在碱性阴离子交换膜燃料电池中得到应用。     

Preparation and investigation of acid–base composite membranes with modified graphitic carbon nanosheets for direct methanol fuel cells

The ethylenediamine-modified graphite oxide (EGO)-doped sulfonated poly (arylene ether ketone) (SPEEK) composite membranes have been prepared and developed for fuel cell applications in the present work. The base-modified EGO improves the dispersion of inorganic nanosheet in the polymer matrix and enhances proton conductivity by creating continuous conduction pathways. Furthermore, the methanol barrier property also be enhanced due to the nanosheet block the methanol-transport channels. EGO-filled membranes display improved dimensional stability, proton conductivity, and ethanol permeability than those using SPEEK control and graphite oxide (GO)-filled membranes. In the direct methanol fuel cells (DMFCs), the SPEEK/EGO-1.5 membrane displays the highest current density of 395.9 mA/cm² at 60°C, which is 1.6- and 1.4-fold higher than that of SPEEK (254.0 mA/cm²) and SPEEK/GO membrane (292.6 mA/cm²).     

Self‐Assembly and Adjustable Ion Conducting Behavior of Graphene Oxide Liquid Crystalline Network Membranes

Self‐assembly of graphene oxide liquid crystalline network (GO‐LCNs) membranes is constructed for the first time via Langmuir–Blodgett assembly technique. The GO‐LCNs are synthesized by hydrogen‐bonded self‐assembly between carboxyl groups on graphene oxide and pyridinyl groups on liquid crystalline polymers. These GO‐LCNs membranes possess distinct microstructures and show adjustable ion conducting behavior due to GO planar structure induced by mesogen oriention of liquid crystal molecules. The liquid crystalline behavior of the GO‐LCNs is identified by combining polarized optical microscopy, differential scanning calorimetry, and X‐ray diffraction measurements. The liquid crystalline properties of GO‐LCNs are adjusted by the composition of the liquid‐crystalline polymers. The microstructures and ion conducting behavior of GO‐LCNs membranes are investigated by applying different electromagnetic field, which are identified by different ionic conductivity of lithium bis(trifluoromethanesulphonyl)imide organic solution passed through the membranes. Ionic conductivity of solutions is increased nearly 100‐fold and tenfold for an orientated GO‐LCNs membrane. These GO‐LCNs are promising materials in numerous applications such as high‐performance electrode material, ion battery materials, proton conductors, and so on.     

氧化石墨烯/磺化聚苯并咪唑高温质子交换膜的制备和表征

通过共混法和原位聚合法成功制备氧化石墨烯（GO）/磺化聚苯并咪唑（SPBI）质子交换复合膜。用FTIR及TEM表征了复合膜的结构,并测试了复合膜的热稳定性、力学性能、尺寸稳定性、含水率、酸掺杂率、氧化稳定性及质子电导率,重点考察不同制备方法、GO的加入对GO/SPBI质子交换复合膜结构和性能的影响。实验结果表明,GO在Y-GO/SPBI-1%复合膜中呈薄片状并良好分散。添加GO后复合膜的力学性能大幅提高,拉伸强度相较于Nafion 117膜（26.65MPa）提高了2.5倍。Y-GO/SPBI-1%复合膜热稳定性稍高于G-GO/SPBI-1%复合膜。Y-GO/SPBI-1%复合膜拥有与SPBI膜相当的含水率,比G-GO/SPBI-1%复合膜的含水率提高了51.36%,表明原位聚合法制备的膜具有良好的保水能力。原位聚合法制备的复合膜具有更高的酸掺杂率和更低的酸溶胀度,提高了膜的尺寸稳定性。Y-GO/SPBI-1%质子交换复合膜在相对湿度40%、160℃下具有最高的质子电导率0.113S/cm。GO上的含氧官能团有助于复合膜中质子的跳跃,原位聚合法使GO更均匀地分散在SPBI基质中,对复合膜质子电导率的提高起到关键作用。     

Highly selective custom-made chitosan based membranes with reduced fuel permeability for direct methanol fuel cells

Custom-made nanocomposite proton exchange membranes (PEMs) are fabricated using the blends of sulfonated chitosan (S-Chitosan) and sulfonated graphene oxide (SGO) nanosheets for direct methanol fuel cells (DMFCs). Sulfonation of chitosan and GO are carried out by 1,3-propane sultone and sulfanilic acid, respectively. Scanning electron microscope (SEM) with energy dispersive X-ray investigation revealed that the thick, folded and wrinkled sheet-like morphology of SGO and the existence of elemental sulfur. SEM and atomic force microscopy images showed the uniform dispersion of hydrophilic SGO nanosheets. Besides the S-Chitosan/SGO membranes showed higher water uptake, swelling ratio and ion exchange capacity due to the enhancement in hydrophilicity. The modified PEMs displayed improvement in proton conductivity since the ion-exchangeable sulfonic acid groups facilitate the proton conduction and effectively resist the methanol permeability by forming a strong hydrogen bond network with chitosan and thus diminish the void volume. Particularly, S-Chiotsan-1 membrane showed superior proton conductivity of 4.86 × 10⁻³ Scm⁻¹ at (25°C), selectivity of 1.89 × 10⁵ Scm⁻³ s and lesser methanol permeability of 2.57 × 10⁻⁸ cm²s⁻¹. Overall results suggest that the S-Chitosan/SGO membranes found to be a suitable alternate for Nafion® in DMFCs.     

Basicity‐based screening of aniline derivative for composite proton exchange membranes

The aim of this study was to find a suitable aniline derivative to develop composite sulfonated poly(ether ether ketone) (SPEEK) membranes and detail evaluation of their physico‐ and electrochemical properties. The hypothesis was high basicity of the aniline derivatives could form good composite membranes with better physicochemical and electrochemical properties. To assess the basicity we measured the zeta potentials of the polymers and correlated them with ion‐exchange capacities, water uptakes, transport numbers, water‐diffusion coefficients, conductivities, and methanol permeabilities. The obtained values of zeta potentials at pH 7 were 6.52, ?14.66, ?25.17, and ?28 for SPEEK/polynaphthalene (PNAPH), SPEEK/polyanisidine (PANIS), SPEEK/polyaniline (PANI), and SPEEK/polyxylindine (PXYL), respectively supports the hypothesis and strongly suggests polyaniline derivative's basicity‐dependent properties. Of the four derivatives (PNAPH, PANIS, PANI, and PXYL), the SPEEK/PXYL composite membrane had the lowest methanol permeability of 1 × 10^?4 cm²/s and highest proton conductivity of 161 mS/cm. These values are far better than the neat SPEEK and SPEEK/PANI composite. The suitability of SPEEK/PXYL can be explained by the high basicity of the PXYL composite membrane, which leads to the formation of effective Debye spheres, meaning that the ionic complex can interact with surrounding hydronium ions and form hydrophilic channels resulting in high proton conductivity and low methanol permeability. These results suggest that SPEEK/PXYL is a highly suitable membrane for methanol fuel cells or other electrochemical applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43978.     

Quaternized poly (2.6 dimethyl – 1.4 phenylene oxide)/Polysulfone anion exchange membrane reinforced with graphene oxide for methanol alkaline fuel cell application

Composite anion exchange membranes (AEM) based on quaternized poly (phenylene) oxide and polysulfone blend (QPPO/PSF) were successfully fabricated and characterized for methanol alkaline fuel cell application. To make a composite AEM, increasing graphene oxide (GO) wt.% ratios was introduced in the polymer blend. The membrane properties were enhanced by the addition of GO in comparison to the bare QPPO/PSF blend. The addition of GO resulted to a higher ion exchange capacity (IEC) of 3.21 mmol.g^?1 and an ion conductivity increase of up to 63.67 mS.cm^?1 at 80 °C. The QPPO/PSF/2%GO composite membrane reached a peak power density of 112 mW.cm^?2, which is about five (5) times more than the parent QPPO membrane at room temperature. The above results indicate that QPPO/PSF/GO is a good candidate as an anion exchange membrane for alkaline fuel cell application.     

Sulfonated graphene oxide‐doped proton conductive membranes based on polymer blends of highly sulfonated poly(ether ether ketone) and sulfonated polybenzimidazole

Simultaneously improving the proton conductivity and mechanical properties of a polymer electrolyte membrane is a considerable challenge in commercializing proton exchange membrane fuel cells. In response, we prepared a new series of miscible polymer blends and thus the corresponding crosslinked membranes based on highly sulfonated poly(ether ether ketone) and sulfonated polybenzimidazole. The blended membranes showed more compact structures, due to the acid‐base interactions between the two constituents, and improved mechanical and morphological properties. Further efforts by doping sulfonated graphene oxide (s‐GO) forming composite membranes led to not only significantly elevated proton conductivity and electrochemical performance, but also better mechanical properties. Notably, the composite membrane with the filler content of 15 wt % exhibited a proton conductivity of 0.217 S cm^?1 at 80 °C, and its maximum power density tested by the H₂/air single PEMFC cell at room temperature reached 171 mW cm^?2, almost two and half folds compared with that of the native membrane. As a result, these polymeric membranes provided new options as proton exchange membranes for fuel‐cell applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46547.