Temperature and Alkali Stable Polymer Electrolytes for Hydrogen and Carbon Dioxide Alkaline Electrolysers

该项目旨在开发基于聚合物电解质的创新电解槽，利用增强的材料和组件降低生命周期成本（通过提高效率实现）。该提议基于采用碱性阴离子交换膜（AEM）和离聚物（AEI）技术，以开辟低成本电解槽系统的机会，该电解槽系统具有：i）低成本聚合物电解质、催化剂（可持续的，即非Pt）和双极板材料; ii）更高的能量效率; iii）持久的长寿命操作;以及iv）响应动态负载操作的灵活性。我们的目标电解槽涉及从水电解制氢和涉及二氧化碳还原低过电位（高价值）有机化学合成。其主要目标是生产下一代AAEM和AEI，可批量供应给（当前和未来）项目合作伙伴（包括溶解形式的AEI）。氢气是可再生和可持续能源系统的优秀储存介质。氢作为能量载体具有几个优点，包括氢和电之间的高效可逆转换，与大多数电池相比压缩气体的良好重量能量密度以及氢技术用于电网规模应用的可扩展性。水电解是在使用点生产纯氢的安全选择，因为它不需要大量的存储要求。目前，通过电解生产氢气的成本高于其他方法，如蒸汽重整。两个主要原因是电池的资本成本和电能消耗。通过水电解的商业氢气生产基于两种技术之一：含水碱性（氢氧化钾）电解质和质子交换膜电解质。碱性电池使用比酸性聚合物系统低成本的电极材料，但电流密度（和效率）通常较低。质子交换膜电解槽的资本成本较高（主要由膜[全氟化聚合物]和贵金属[Pt、Ir、Ru]基催化剂的高材料成本决定），但它们的生产率（每单位电极面积）基于较高的电流密度而较高。因此，我们寻求通过结合碱性电解质和聚合物电解质的优势，使用低成本材料来改造后者的技术，以提高能源效率。实际上有一个最低的能源消耗，可以通过电解实现（基于电池中的热力学势和电压损失），因此我们将我们的目标设定为在1 A cm-2下1.75 V的电压（基于几何电极面积）。为了最大化正在开发的材料的潜在影响，此外，亦会研究二氧化碳还原电解槽（涉及二氧化碳利用的范畴）。从可持续性、环境和社会角度来看，将二氧化碳还原为有用的化学品具有巨大的潜在价值。这种合成需要大量的能源使用，因此在这种应用中使用可再生电能可以在其发展中发挥重要作用。因此，我们寻求开发电化学技术，由此我们基于阴离子交换膜电解槽材料和架构（包括碳酸根阴离子传导电解质的参与-与氢氧化物传导类似物相比，其固有地产生更高的化学稳定性）合成小分子（甲酸盐、合成气和/或甲醇）。该项目旨在实现超低碳、绿色氢生产和二氧化碳减排系统的逐步转变。这将基于申请人先前的碱性聚合物电解质材料和非贵金属催化剂的技术突破的应用，用于电流和电解电化学能量转换和存储技术。

The project aims to develop innovative polymer electrolyte based electrolysers with lower life cycle costs (achieved by enhanced efficiency) utilising enhanced materials and components. This proposal is based on adopting alkaline anion-exchange membrane (AEM) and ionomer (AEI) technology to open up the opportunity for low cost electrolysers systems with: i) low cost polymer electrolytes, catalysts (sustainable i.e. non-Pt), and bipolar plate materials; ii) higher energy efficiency; iii) durable long life operation; and iv) flexibility to respond to dynamic load operation. We target electrolysers involving hydrogen production from water electrolysis and involving carbon dioxide reduction for low overpotential (high value) organic chemical synthesis. A major aim is to produce the next generation of AAEMs and AEIs that can be supplied to (current and future) project partners in bulk quantities (including AEIs in a solubilised form).Hydrogen is an excellent storage medium for renewable and sustainable energy systems. Hydrogen has several advantages as an energy carrier including highly efficient reversible conversion between hydrogen and electricity, good gravimetric energy density of compressed gas compared to most batteries and scalability of hydrogen technologies for grid scale applications. Water electrolysis is a safe option for production of pure hydrogen at point of use as it does not require substantial storage requirements. Currently, the cost of hydrogen produced by electrolysis is greater than that of other methods such as steam reforming. Two major reasons for this is the capital cost of the cells and the electrical energy consumption. Commercial hydrogen production by water electrolysis is based on one of two technologies: aqueous alkaline (potassium hydroxide) electrolytes and proton exchange membrane electrolytes. Alkaline cells use lower cost electrode materials than acid polymer systems but current densities (and efficiency) are typically lower. The capital cost of proton exchange membrane electrolysers is higher (largely dictated by the high material costs of membranes [perfluorinated polymers] and precious metal [Pt, Ir, Ru] based catalysts) but their production rates (per unit electrode area) are higher based on the higher current densities. We thus seek to transform the latter technology by combing the advantages of alkaline and polymer electrolytes using low cost materials with the aim of improving energy efficiencies. Realistically there is a minimum energy consumption that can be achieved by electrolysis (based on thermodynamic potentials and voltage losses in the cell) and thus we set our target at a voltage of 1.75 V at 1 A cm-2 (based on geometric electrode area).To maximise the potential impact of the materials being developed, carbon dioxide reducing electrolysers will also be studied (involving the field of carbon dioxide utilisation). The reduction of carbon dioxide into useful chemicals is of great potential value from a sustainability, environmental and societal context. Such syntheses require a significant energy use and thus using renewable electrical energy in such applications could play a major part in their development. Consequently we seek to develop electrochemical technology whereby we synthesis small molecules (formate, synthesis gas, and/or methanol) based on anion exchange membrane electrolyser materials and architectures (including the involvement of carbonate anion conducting electrolytes - which inherently yield higher chemical stabilities compared to hydroxide conducting analogues). The project aims to deliver a step change in uptake of ultra-low carbon, green-hydrogen production and carbon dioxide reduction systems. This will be based upon the application of the applicants previous technology breakthroughs of alkaline polymer electrolyte materials and non-precious metal catalyst for galvanic and electrolytic electrochemical energy conversion and storage technologies.