Effect of Accelerated Chemical Degradation on the Surface Roughness Parameters and Morphology of Fuel Cell Membranes

摘要

Nafion^? membranes are proton conducting membranes that are widely used in fuel cells. This study investigates the surface roughness evolution and morphology change in the Nafion^? 212 membrane (N212) subjected to two types of artificial degradation. Although some previous investigations have clearly observed the difference in morphological changes of the membrane subjected to different accelerated degradation techniques, very scant information available on the roughness parameters of the membrane. Given the rough surface nature of the catalyst layer (CL), information obtained from the present investigation can be helpful in understanding the interfacial stability of the membrane electrode assembly (MEA). We distinguish and compare the morphological changes in the membrane with the published observations and note that different accelerated degradation mechanisms lead to distinguished changes in the N212 morphology. Two chemical degradation techniques adopted here are – Ion exchange method and Solution method. Tapping mode - AFM (TM-AFM) and SEM is used in investigating the roughness parameters and surface morphology of the fresh as well as degraded N212.