(480d) Controlling Water at Catalyst/Ionomer Interface with Molecular Additives

The growth and viability of deep decarbonization through the hydrogen economy is dependent upon scientific advances that will address the existing political, regulatory, and technological barriers that currently hinder electrochemical energy technologies. The strong correlation between device-level performance and catalytic electrode activity/durability highlights the criticality of identifying the limiting processes and developing strategies to address these limitations. For proton exchange membrane fuel cell and water electrolyzers (PEMFC and PEMWE), many of the existing limitations can be traced to the interface between catalyst materials and ion conducting electrolytes, be they aqueous-based or solid electrolytes. The catalyst/ionomer interface is plagued by negative impacts to both reaction kinetics and reactant transport. Mitigating these impacts while maintaining sufficient ionic transport and contact in device catalyst layers is challenging. In this talk, we will present our work with molecular interfacial modifying species and their role in alleviating many of the detrimental impacts of the ionomer/catalyst interface. Additionally, we will highlight the role of water in defining catalyst performance at these interfaces and how we can optimize the interaction of solvating water with the catalyst surface to improve reaction kinetics.