Favero Silvia, Stephens Ifan E L, Titirci Maria-Magdalena
Department of Chemical Engineering, Imperial College London, England, SW7 2BU, UK.
Department of Materials, Imperial College London, England, SW7 2BU, UK.
Adv Mater. 2024 Feb;36(8):e2308238. doi: 10.1002/adma.202308238. Epub 2023 Dec 3.
Alkaline-based electrochemical devices, such as anion exchange membrane (AEM) fuel cells and electrolyzers, are receiving increasing attention. However, while the catalysts and membrane are methodically studied, the ionomer is largely overlooked. In fact, most of the studies in alkaline electrolytes are conducted using the commercial proton exchange ionomer Nafion. The ionomer provides ionic conductivity; it is also essential for gas transport and water management, as well as for controlling the mechanical stability and the morphology of the catalyst layer. Moreover, the ionomer has distinct requirements that differ from those of anion-exchange membranes, such as a high gas permeability, and that depend on the specific electrode, such as water management. As a result, it is necessary to tailor the ionomer structure to the specific application in isolation and as part of the catalyst layer. In this review, an overview of the current state of the art for anion exchange ionomers is provided, summarizing their specific requirements and limitations in the context of AEM electrolyzers and fuel cells.
基于碱性的电化学装置,如阴离子交换膜(AEM)燃料电池和电解槽,正受到越来越多的关注。然而,尽管对催化剂和膜进行了系统研究,但离聚物在很大程度上被忽视了。事实上,大多数碱性电解质的研究都是使用商业质子交换离聚物Nafion进行的。离聚物提供离子导电性;它对于气体传输和水管理以及控制催化剂层的机械稳定性和形态也至关重要。此外,离聚物有与阴离子交换膜不同的独特要求,如高气体渗透性,并且这些要求取决于特定电极,如水管理。因此,有必要将离聚物结构定制为适用于特定应用,既单独使用,也作为催化剂层的一部分。在这篇综述中,概述了阴离子交换离聚物的当前技术状态,总结了它们在AEM电解槽和燃料电池背景下的特定要求和局限性。