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质子交换膜水电解(PEMWE)制氢具有可适用于风能太阳能等可再生能源的间歇性和波动性、能量转换效率高、启动快速、占地小等优点,成为目前绿氢制取重点关注的技术。膜电极作为水电解制氢关键核心部件,对于水电解制氢的性能、效率和寿命至关重要,并随着量产规模的扩大在系统成本中的占比越来越高。发展高性能、低成本和高耐久性的膜电极对于绿氢的低成本大规模制取具有重要意义。本文综述了近年来质子交换膜电解水制氢膜电极中质子交换膜、催化层、多孔传输层等关键材料部件以及膜电极制备技术的研究进展和成果,并进行了简要评述。从膜电极设计和开发的角度系统地梳理了如何提高电解制氢性能、降低水电解制氢膜电极成本等方面的进展。最后,就未来膜电极研发的方向提出了建议。 相似文献
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以氯铱酸为前体,钛网为支撑体,二氧化钛为载体,采用浸渍-热分解法首次成功制备了一体化IrO2-TiO2/Ti析氧电极,进一步采用热压法制备膜电极(MEA)。综合扫描电镜(SEM)、循环伏安(CV)、交流阻抗(EIS)以及单池极化曲线测试,研究了载体对于析氧电极形貌以及性能的影响。结果表明:未加入载体二氧化钛的析氧电极表面以裂缝为主,孔隙率较低;而加入载体二氧化钛的析氧电极表面裂纹基本消失,取而代之的是大量的催化剂簇以及孔结构的生成,极大地提高了析氧电极的电催化活性。单池测试表明,电流密度为1000mA/cm2时,添加载体二氧化钛后制备的析氧电极的析氧电位大约是1.70V。 相似文献
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开发清洁高效的可再生能源是未来能源转型的必然趋势。氢能作为一种绿色无污染的能源载体,可通过电解水技术实现氢能与电能的高效转化,有望作为风力、光伏发电的重要调节手段。碱性膜电解水制氢能够提高电流密度,增加能量转化效率,优于碱性水溶液电解水制氢;与此同时,可采用铁、镍等非贵金属制备催化剂,克服质子交换膜电解水制氢使用贵金属催化剂带来的设备昂贵、资源受限问题。本文综述了碱性膜电解制氢技术发展现状,重点围绕自支撑催化电极、耐碱腐蚀离子膜、有序结构膜电极开展讨论,包括催化剂制备策略,耐碱离子膜发展现状,以及有序化膜电极的应用优势,阐释电化学工程中的传质与反应耦合原理。本文为进一步研究开发高性能电化学关键材料提供了指导思路,推动电解水制氢技术的发展。 相似文献
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A new chlorine resistant anion exchange membrane enables innovative possibilities for hydrochloric acid electrolysis for recovery
of chlorine. This is of interest for hydrochloric acid that is neutralized in the chemical industry because purity and concentration
are not sufficiently high for recycling. In the common electrolysis process hydrochloric acid is fed into the anode compartment
and needs a satisfactory HCl concentration for supplying the anode with chloride ions. Using an anion exchange membrane as
a cell separator the feed flows into the cathode chamber where a low HCl concentration is acceptable because Cl− ions at the anode can be supplied by addition of a salt which is not consumed. Experimental data of the membrane and the
process are presented: membrane permselectivity improved up to above 97% using CaCl2 as added salt, chlorine current efficiency up to 98% and oxygen content as low as 0.5 vol%, cell voltage at 4 kA m−2 2.3 V, equivalent to 1740 kWh per t produced chlorine, even at low HCl concentrations. Thus, the power consumption is comparable
with the common process. A problem of the new process is the high water transport through the membrane. Therefore, experiments
for two process alternatives were carried out. Disadvantages of water transport can be avoided by using a high concentrated
CaCl2 solution as anolyte and catholyte and as absorption medium for diluted HCl gas streams. Additionally, a cell design was investigated
where the anode is directly connected to the membrane in an empty (gas filled) anode compartment. 相似文献
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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。 相似文献
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以1-甲基咪唑(N-MI)为季铵化试剂一步法对聚氯乙烯(PVC)功能化改性,并制备了均相PVC阴离子交换膜,避免了传统阴离子交换膜制备过程中的氯甲基化步骤。通过对比研究,优化后的PVC-N-MI-5表现出较好的综合性能。离子交换容量和迁移数分别高达2.89 mmol·g–1和98.4%;吸水率和溶胀率分别为4.24%和0.21%,低于商业JAM-5阴离子交换膜(4.87%和3.33%);脱盐率、电流效率以及能耗分别为98.38%、55.8%和5.1 kW·h·(kg NaCl)–1,可与商业JAM-5(93.0%、55.2%和4.6 kW·h·(kg NaCl)–1)相比较。低廉的原料与简便的制备过程以及相对良好的电渗析应用性能,表明所制备的PVC-N-MI-5具有一定的应用前景。 相似文献
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燃料电池技术作为一种绿色能源技术,在减少能源消耗、环境污染等方面具有巨大潜力。膜电极(MEA)是质子交换膜燃料电池(PEMFC)的核心部件,MEA中电化学反应的顺利进行需要各功能层的协调配合,MEA各功能层涉及的传质、导电、导质子、催化等方面均影响燃料电池的性能。根据制备方法,可以将MEA分为催化剂涂敷基底(CCS)型MEA、催化剂涂敷膜(CCM)型MEA、有序化MEA和一体化MEA。MEA的性能不仅由催化剂本身载量决定,也受其结构设计和制备工艺的影响。本文介绍了MEA制备过程中常见的改进方法,分别从催化剂喷涂、刮涂、模槽挤出涂覆方式,催化剂浆料组成中Nafion含量和溶剂极性选择,催化层梯度化、图案化及界面结构改进,PEM结构增强、图案化、成膜方式等方面的研究进展进行讨论。但是目前对于MEA各功能层界面间的研究较少,应该注意的是催化层/质子交换膜(PEM)界面以及催化层/气体扩散层(GDL)界面设计也将直接影响MEA的性能。 相似文献
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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. 相似文献
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氢能是支撑起智能电网和可再生能源发电规模化的最佳能源载体,而电解水制氢是实现制氢规模化的重要途径。在多种电解水制氢技术中,质子交换膜电解水技术由于具备电流密度大、产氢纯度高、响应速度快等优势,吸引了科学界和工业界的广泛重视。本文首先介绍了质子交换膜电解池的结构组成以及各组成的主要作用,对比分析了碱性电解池、固体氧化物电解池与质子交换膜电解池的技术差异,并结合电解水析氢反应以及析氧反应的机理阐释,分别介绍了两步半反应的常用催化剂;然后,从最初的实验室研究阶段到目前兆瓦级别的质子交换膜电解水系统,回顾了该技术的发展历程以及应用现状;其次,从制氢成本、电堆性能及电堆寿命等多角度分析目前该技术面临的瓶颈问题;最后,根据质子交换膜电解池的技术优势,并针对上游间歇性可再生能源的需求以及和下游产业的联合应用,对其未来前景进行了展望。 相似文献
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通过对集团公司自己组织设计、调试、开车的1万t/a离子膜电解装置项目进行总 结,客观评价项目运作过程中存在的问题,以备参考。 相似文献
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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。 相似文献
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Mechanical robustness and durability are crucial for anion exchange membranes to guarantee the longevity and consistent performance of AEM water electrolysis (AEMWE) systems. In this study, a composite membrane based on the quaternized poly(p-phenylene oxide) (QPPO)/polytetrafluoroethylene (PTFE) was developed. This membrane was fabricated by enhancing the QPPO-based AEM through a pore-filling technique within a porous PTFE structure. The tensile strength of the composite membrane was increased significantly from 16.5 to 31 MPa. The conductivity of the composite membrane was 6.25 mScm−1 lower than 30 mScm−1 of the QPPO-based membrane at 20°C, resulting from the low volume fraction of QPPO in the composite membrane. At 40% RH, the net change mass of the composite membrane is 1.59%, much lower than that of QPPO-based membrane (10.98%) at 40°C. The composite membrane demonstrated a significantly increased lifetime in the working electrolyzer (>200 h) compared with an otherwise identical electrolyzer assembled with a QPPO-based membrane (50 h). 相似文献
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Transport numbers of several aliphatic and aromatic carboxylate ions across an anion exchange membrane were determined on the basis of the transport number of the co-ions across the membrane in electrodialysis. Also, the specific conductivity and water content of each carboxylate ionic-form membrane were measured.The transport number of lower aliphatic carboxylate ions decreases slowly with increasing molecular weight, but it decreases markedly where the carbon number is over five. In particular, the transport number of caprylate or of caprate ions is below 0.5, and these ionic-form membranes apparently lose the characteristics of an anion exchange membrane. For aromatic carboxylate ions, the benzoate ion a higher transport number, but p- or O-hydroxybenzoate ions only about 0.6. The specific conductivity and water content of each carboxylate ion having a lower transport number are very small compared with other carboxylate ions of higher transport number. This suggests that the hydration number and the activity of ions with a lower transport number are small in anion exchange membranes. 相似文献
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聚偏氟乙烯(PVDF)因含氟乙烯基单体,拥有良好的化学稳定性、热学稳定性和机械性能,与其他高分子膜材料相比更容易提高离子交换膜的性能。本实验采用热压法制备PVDF聚乙烯阴离子交换膜,探讨了PVDF含量对膜性能的影响,如膜电阻、离子交换容量、耐破度、含水率和选择透过性。利用红外光谱仪及扫描电子显微镜表征手段对PVDF膜表面性质和结构进行了分析。结果表明,当PVDF含量增加时,膜面电阻、耐破度升高。离子交换容量、含水率,反离子选择透过性降低。虽然PVDF的添加导致含水率、交换容量等膜性能的下降,但耐破度的升高表明膜稳定性和机械性能得到了提升,这赋予PVDF聚乙烯膜一定的使用价值。 相似文献