Photocrosslinked Hydroxide Exchange Membranes for Alkaline Fuel Cells

迫切需要制造更有效的氢氧化物交换膜以实现新一代碱性燃料电池。 膜必须表现出可接受的导电性、碱性稳定性和易于制造，以使相对便宜的氢氧化物交换燃料电池（HEFC）成为可行的能源选择。 虽然质子交换燃料电池（PEFC）最近已经获得了很多关注，但氢与质子的反应通常需要昂贵的贵金属催化剂，如铂，这对于大规模应用来说既不经济又不可持续。 通过改变燃料电池的操作，使得氢氧化物在阴极产生并穿过膜，PI可以使用更便宜的催化剂，例如镍合金。 该项目的重点是两个PI之间的协同合作，在燃料电池和聚合物网络方面具有互补的技能。 他们计划共同创造一种新型的光固化，碱稳定，廉价的膜材料，具有高氢氧化物导电性。 具体而言，该项目的目标有四个方面：1）使用新的化学方案合成、交联和表征具有季鏻侧基官能团以及光诱导交联能力的单体和聚合物; 2）配制这些新的单体和聚合物组合物以优化它们的膜性能，例如溶胀、机械强度、耐碱性降解性，和三个氢氧化物交换燃料电池膜层（阴极、膜和阳极）中的每一个的氢氧化物电导率; 3）用优化的材料制造膜电极组件，利用它们的时空交联控制来制造复杂的HEFC设计，并展示这些材料在器件小型化和电池方面的能力。制造复用; 4）培养化学合成、高分子化学和膜分离方面的本科生和研究生。 光介导的交联将不仅提供在HEFC中至关重要的尺寸稳定的膜，而且还能够实现用于制造复杂膜电极组件的新方法。 该项目的结果将增加对分子组成如何影响膜性能和性质的理解。 所提出的合成策略允许的几何构型和膜结构进行精确的调整，这将提供洞察氢氧化物的导电性，气体交换和运输在一个尺寸稳定的膜之间的复杂的相互作用。 更广泛的影响。 不同的人员将参与化学反应和工程，聚合物工程和下一代能源应用的独特组合。 首席PI参与外展活动，如特拉华州大学工程发现计划，该计划针对K-12学生和家长。 PI将开发一个演示模块，向K-12学生和家长解释膜。 该项目的潜在转型方面是材料的制造，这些材料将在实现碱性燃料电池的低成本膜方面发挥重要作用，从而实现低碳足迹的能源。

1264503 KloxinThere is a critical need to create more effective hydroxide exchange membranes to enable a new generation of alkaline fuel cells. Membranes must exhibit acceptable conductivity, alkaline stability, and easy fabrication to make the relatively inexpensive hydroxide exchange fuel cell (HEFC) a viable energy option. Although proton exchange fuel cells (PEFCs) have garnered much of the recent attention, the reaction of hydrogen to protons commonly requires expensive precious metal catalysts, such as platinum, which is both uneconomical and unsustainable for large-scale applications. By changing the operation of the fuel cell such that hydroxide is produced at the cathode and passed through the membrane, the PIs can employ cheaper catalysts, such as nickel alloy. The focus of this project is a synergistic collaboration between two PIs, having complementary skills in fuel cells and polymer networks. Together they plan to create a novel photo-cured, alkaline-stable, and inexpensive membrane material with high hydroxide conductivity. Specifically, the aims of the project are fourfold: 1) synthesize, crosslink, and characterize monomers and polymers having quaternary phosphonium pendant functional groups as well as photo-induced crosslinking capability using novel chemical schemes; 2) formulate these novel monomer and polymer compositions to optimize their membrane properties, such as swelling, mechanical strength, alkaline degradation resistance, and hydroxide conductivity for each of the three hydroxide exchange fuel-cell membrane layers: cathode, membrane, and anode; 3) create a membrane electrode assembly with the optimized materials, exploiting their spatiotemporal crosslinking control to fabricate complex HEFC designs as well as demonstrate the capability of these materials in device miniaturization and cell fabrication multiplexing; and 4) train a diverse group of undergraduate and graduate students in chemical synthesis, polymer chemistry, and membrane separations. Photo-mediated crosslinking will not only provide a dimensionally stable membrane, which is critical in HEFCs, but also enable a new method for fabricating complex membrane electrode assemblies. The results of this project will increase the understanding of how molecular composition influences membrane performance and properties. The proposed synthetic strategy allows the geometric configuration and membrane structure to be precisely tuned, which will provide insight into the complex interplay between hydroxide conductivity, gas exchange, and transport within a dimensionally stable membrane. Broader Impacts. Diverse personnel will be involved in a unique combination of chemical reactions and engineering, polymer engineering, and next-generation energy applications. The lead PIs are involved in outreach activities such as the University of Delaware Engineering Discovery Program, which targets K-12 students and parents. The PIs will develop a demonstration module to explain membranes to K-12 student and parents. The potential transformational aspect of the project is the fabrication of materials that will play a significant role in the realization of lower cost membranes for alkaline fuel cells, leading to an energy source with a low-carbon footprint.