The effects of cationic impurities on the performance of proton exchange membrane water electrolyzer

This paper investigates the effects of impurities contamination on the performance of a proton exchange membrane (PEM) water electrolyzer. The impacts of Fe3+, Cu2+ and Al3+ ions on the performance of single PEM water electrolysis cells are investigated by introducing Fe2(SO4)3, CuSO4, Al2(SO4)3 solution into deionized water to prepare 5 parts per million (ppm, molar ratio) contaminated feed solution. The prepared solution was then fed to the PEM water electrolysis system to carry out the contamination test. The results show that the single cell performance experienced a dramatic decrease initially but then recovered to some degree during the Fe3+ ions contamination. For Cu2+ ions contamination, the cell ohmic resistance decreased while the charge and mass transfer resistance showed an increasing trend throughout the test period. Moreover, the Al3+ ions can cause a sudden cell failure when introduced into the cell.