电压循环工况对PEMFC阴极催化层衰减机制的影响OA

This study investigates the impact of voltage cycling conditions on the stability of the catalyst layer in proton exchange membrane fuel cells(PEMFCs).The results show that under high-voltage cycling(0.6～0.95 V),cell performance deteriorates significantly,with a 3.5％drop in open-circuit voltage and a 64％decrease in current density at 0.65 V.This is mainly due to accelerated dissolution and agglomeration of platinum(Pt),resulting in a 50％loss of electrochemical active surface area(ECSA)and increased corrosion of the carbon support.In contrast,low-voltage cycling(0.4～0.85 V)shows better stability,with only a 36％decrease in current density and a 30％loss of ECSA,as the milder potential window inhibits Pt dissolution and carbon support corrosion.Electrochemical impedance spectroscopy(EIS)analysis reveals that high-voltage cycling significantly increases charge transfer resistance,while low-voltage cycling mainly causes an increase in proton conduction impedance.Therefore,high voltage is a key factor affecting catalyst durability,and the voltage cycling range has a decisive impact on the attenuation behavior of PEMFC catalysts.