(339c) Nanoscale Design of Electrocatalysts for Alkaline Fuel Cell and Electrolyzer Applications

Authors: 
Lee, S. W., Georgia Institute of Technology
Kavian, R., Georgia Institute of Technology

Over the last decade, hydrogen has been considered as the key energy carrier, which can be used to convert renewable energy sources via electrochemical energy conversion devices, such as electrolyzers and fuel cells. Utilization of hydrogen depends on two fundamental electrochemical reactions: the hydrogen evolution reaction (HER) in electrolyzers, and its reverse, the hydrogen oxidation reaction (HER) in fuel cells. Although the reaction kinetics of both HER and HOR in alkaline media are significantly slower compared to those in acid electrolytes, the activity trends in alkaline electrolytes have been much less explored. Recent single crystal study has shown that a delicate balance between adsorbed H and adsorbed OH on the bimetallic surfaces can significantly improve both HER and HOR activity in alkaline electrolytes. Thus, the application of the bimetallic mechanisms to design active nanoscale catalysts with sizes of practical relevance is imperative to develop high performance alkaline fuel cells and electrolzyers. In this work, we investigate the HER and HOR in alkaline electrolytes on metal nanoparticles to achieve fundamental understanding of the relationship between surface atomic structure and electrocatalytic activity, using novel synthesis methods and thorough electrochemical characterizations, which aims at developing active nanoscale electrocatalysts.