Next generation anion-exchange membranes (AEM) with covalently-bound antiradical functions for enhanced durability

开发分别使用（发电）和产生可持续氢气的基于阴离子交换膜（AEM）的燃料电池（AEMFC）和碱性水电解槽（AEM-AWE）的主要动机是最小化贵金属电催化剂的使用的潜力（参见图1）。质子交换膜等效物）;这将降低成本，并导致系统只涉及地球上丰富的元素（确保可持续性）。此外，AEM-AWE使用低浓度碱水或纯水进料（参见传统的非AEM碱性水电解槽），无需处理大量高腐蚀性溶液（这会带来与泄漏和处置相关的重大环境影响）。AEMFC最初将用于备用电源固定部门（包括电信）取代柴油发电机，减少噪音和当地污染物排放，为消费者提供更多便利：目前的柴油发电市场供应200吉瓦的全球电力需求（2015年价值90亿英镑）。预计2018 - 28年间全球氢电解槽市场的复合年增长率为7.2%（市场预计到2028年将达到4.263亿美元），西欧运输领域的应用预计将以显著的速度增长["氢电解器市场：碱性电解器预计到2028年仍将是主导产品类型：全球行业分析2013 - 17和机会评估2018 - 28 "，未来市场洞察报告，2019年]。申请人是碱性聚合物电解质材料（膜和粉末形式，后者用于电极制造）开发的世界领导者，特别是辐射接枝类型。机械坚固、碱稳定和高性能（高电导率、高水传输）的材料已被证明可用于AEMFC和AEM-AWE（温度高达80摄氏度）。碱稳定性的改善意味着氧化自由基降解机制变得相对重要，现在需要成为研究重点。本项目的重点是开发两类具有进一步增强化学稳定性的AEM（碱和自由基氧化），但其中机械，离子传输和水传输性能不牺牲：（1）下一代辐射接枝AEM（RG-AEM）和（2）新的尺寸稳定的、机械强度强的孔填充AEM（PF-AEM）。重点将放在将乙烯基-酚组分共掺入RG-AEM中，其中这种共价结合的酚组分可作为自由基捕获剂以增强自由基-氧化稳定性。其次，我们先前的RG-AEM研究还确定了几种新的先进单体（如3-乙烯基苄基氯），其可以形成具有增强的碱稳定性的RG-AEM，但不幸的是，具有差的离子电导率和水传输性能（因为由于这种接枝的基于粗自由基的性质，这种单体不能以足够的水平进行辐射接枝）。因此，这些先进的单体将用于制造PF-AEM，其可以使用替代的聚合方法（例如阳离子或先进的受控自由基聚合）制造。第三，这些新型PF-AEM也可以与乙烯基酚单体共结合，以生产具有最大化学和机械稳定性的材料。RG-AEM和PF-AEM将在AEMFC和AEM-AWE中进行评估，以最大限度地提高商业化机会。这将极大地涉及我们的工业项目合作伙伴：AFC能源（邓斯福尔德，萨里郡）将利用其燃料电池组件集成技术和IP（用于备用电源部门），协助将材料开发转化为中试规模的AEMFC演示系统。PV3 Technologies（Cornwall）将通过材料交换和评估以及在其设施中扩大AEM-AWE技术来协助AEM-AWE的开发。

The prime motivation in the development of anion-exchange membrane-(AEM)-based fuel cells (AEMFC) and alkaline water electrolysers (AEM-AWE), that use (generate electricity) and produce sustainable hydrogen respectively, is the potential to minimise the use of precious metal electrocatalysts (cf. proton-exchange membrane equivalents); this will reduce costs and lead to systems involving only earth abundant elements (ensures sustainability). Additionally, AEM-AWEs use low-concentration aqueous-alkali or pure-water feeds (cf. traditional non-AEM alkaline water electrolysers), eliminating the need to handle large quantities of highly caustic solution (that comes with significant environmental implications related to leakage and disposal).The AEMFCs will initially be targeted in the backup power stationary sector (including for telecoms) to replace diesel generators with the added consumer convenience of reduced noise and local emissions of pollutants: the current diesel generation market supplies 200 GW of global power demand (valued at £9B in 2015). The global hydrogen electrolyser market is estimated to register a compound annual growth rate of 7.2% between 2018-28 (market expected to reach US$426.3M by 2028), with application in the transport segment expected to grow at a significant pace in Western Europe ["Hydrogen Electrolyzer Market: Alkaline Electrolyzer Expected to Remain Dominant Product Type Through 2028: Global Industry Analysis 2013-17 and Opportunity Assessment 2018-28", Future market insights report, 2019].The applicants are world-leaders in the development of alkaline polymer electrolyte materials (membranes and powdered forms, the latter for use in electrode manufacture), especially radiation-grafted types. Mechanically robust, alkali stable, and high performance (high conductivity, high water transport) materials have been demonstrated for use in both AEMFCs and AEM-AWEs (temperatures up to 80 degC). The recent improvements in alkali stability means that oxidative-radical degradation mechanisms become relatively significant and now need to be a research focus. The focus of this project is to develop two classes of AEM with further enhanced chemical stabilities (both alkali and radical-oxidative), but where mechanical, ion-transport and water transport properties are not sacrificed: (1) next generation radiation-grafted AEMs (RG-AEM) and (2) new dimensionally-stable, mechanically-strong pore-filled AEMs (PF-AEM).Firstly, the focus will be on the co-incorporation of vinyl-phenolic components into RG-AEMs, where such covalently-bound phenolic components can act as radical traps to enhance radical-oxidative stabilities. Secondly, our prior RG-AEM research has also identified several new advanced monomers (such as the 3-vinylbenzyl chloride) that can form RG-AEMs with enhanced alkali stabilities but, unfortunately, poor ion conductivities and water transport properties (as such monomers cannot be made to radiation-graft at adequate levels, due to the crude radical-based nature of such grafting). Hence, these advanced monomers will be used to make PF-AEMs, which can be fabricated using alternative polymerisation methods (e.g. cationic or advanced controlled-radical polymerisation). Thirdly, co-incorporation of vinyl-phenolic monomers will also be possible with these new PF-AEMs to produce materials with maximised chemical and mechanical stabilities.The RG-AEMs and PF-AEMs will be evaluated in both AEMFCs and AEM-AWEs, to maximise the commercialisation opportunities. This will heavily involve our industrial project partners: AFC Energy (Dunsfold, Surrey) will assist with translating the materials developments into pilot scale AEMFC demonstrator systems, using their fuel cell component integration knowhow and IP (for the backup power sector). PV3 Technologies (Cornwall) will assist with AEM-AWE developments by materials exchange and evaluation and scale-up of AEM-AWE technology in their facilities.