Revealing the Internal Architecture of Alkaline Fuel Cell Membranes with Cryo-4D-STEM and Cryo-STEM-EELS

Characterization of the internal architecture of polymer materials plays an important role in the development of energy devices such as fuel cells. The beam sensitivity of polymer materials coupled with their inherent low contrast makes imaging using conventional TEM and STEM techniques a challenge. Here, we demonstrate robust mapping of the internal architecture of fuel cell polymer membranes using cryo-4D-STEM and cryo-STEM-EELS. We will focus on characterization of alkaline anion exchange membranes (AAEMs) used in AAEM fuel cells, a cheaper alternative to current fuel cell technologies as they allow for platinum group metal-free catalysts [1]. In fuel cell polymer membranes, the internal architecture is critical in performance metrics such as conductivity, mechanical durability, and chemical stability.