Investigating Non-Precious Metal Catalyst-Electrolyte Interface in Anodes for Alkaline Fuel Cells

Abstract

Extensive research is being performed in renewable and sustainable energy to satisfy the world’s demand and reduce carbon dioxide emissions. Part of these efforts focuses on the development of energy conversion devices such as fuel cells. Alkaline membrane fuel cells (AMFCs) gained attention due to their good activities for oxygen reduction reaction (ORR) in high pH environments using non-precious metal catalysts.1 However, the hydrogen oxidation reaction (HOR) activities with non-precious metal catalysts are still low and poorly understood. Our previous research3,4 with Pt catalysts in alkyl ammonium and guanidinium alkali organic solvents indicated that the HOR activity of Pt is limited by cationic group adsorption at the surface of the catalyst, showing the performance of fuel cells rapidly degraded. In this presentation, we expand our investigation to the HOR interfacial behavior of non-precious Ni-based catalysts-quaternary ammonium functionalized ionomers using microelectrode set-up. Our data suggests that the time-dependent cationic group adsorption with the non-precious metal catalyst is less than that of the Pt catalysts, in spite of the much lower HOR initial activity of the non-precious metal catalysts. Here we will present the microlectrode and surface-FTIR mechanism studies of the interaction of non-precious metal catalyst and various quaternized alkaline polymer electrolytes and their impact on the kinetics of HOR under high pH conditions. Acknowledgment This work is supported by US Department of Energy, Energy Efficiency and Renewable Energy, Fuel Cell Technology Office.