The Asymmetric Effects of Cu2+ Contamination in a Proton Exchange Membrane Fuel Cell (PEMFC)

Abstract

AbstractIn this work, we investigate the effects of Cu2+ contamination on the cathode, anode and membrane of a 50 cm2 acitve area membrane electrode assembly (MEA) in a proton exchange membrane fuel cell (PEMFC), by using carbon supported dealloyed PtCu3 nanoparticles as the cathode electrocatalysts. PtCu3 is dealloyed with nitric acid at 25 °C and 80 °C for different dealloying harshness. It is found that the MEA with the catalyst dealloyed at 25 °C has a higher performance at low current density region, while it has a lower performance at medium to high current density region, compared to the MEA with the catalyst dealloyed at 80 °C. The contamination effect is found to be asymmetric to the cathode, anode and membrane in an operating PEMFC. Accumulation of Cu2+ takes place at the cathode due to the electric field through the thickness direction of the MEA, detrimenting the proton transport in the cathode and causing a high cathode sheet resistance. This detrimental effect becomes more severe when PEMFC operating at high current density and low humidity, which is rationalized in detail in the discussion. Mitigation strategy of copper cation contamination on PEMFC performance has been proposed to ensure successful application of carbon supported Pt‐Cu alloy electrocatalysts with high activity in PEMFCs.