英译汉：Oxygen permeation in proton exchange membrane (PEM) water electrolyzers is a critical phenomenon. Mainly, because of (i) degradation and (ii) purity of the hydrogen product gas. Additionally, but less important because of (iii) efficiency loss and (iv) safety problems. Despite these issues, oxygen permeation in PEM water electrolysis was paid less attention. This can be explained by the low oxygen crossover compared to the hydrogen crossover. In this contribution the oxygen content within the hydrogen product gas was measured for two different cathodic catalyst materials (Pt and a Pt-free catalyst) during water electrolysis in a current density range of 0.05–2 A/cm2 . In comparison to the platinum catalyst, the Pt-free catalyst leads to 3–4 times higher oxygen contents within the hydrogen product gas. This can be explained with a lower activity concerning oxygen recombination, so that less permeated oxygen is consumed and consequently, the oxygen flux within hydrogen is higher.

已完成理解「英译汉：Oxygen permeation in proton exchange membrane (PEM) water electrolyzers is a critical phenomenon. Mainly, because of (i) degradation and (ii) purity of the hydrogen product gas. Additionally, but less important because of (iii) efficiency loss and (iv) safety problems. Despite these issues, oxygen permeation in PEM water electrolysis was paid less attention. This can be explained by the low oxygen crossover compared to the hydrogen crossover. In this contribution the oxygen content within the hydrogen product gas was measured for two different cathodic catalyst materials (Pt and a Pt-free catalyst) during water electrolysis in a current density range of 0.05–2 A/cm2 . In comparison to the platinum catalyst, the Pt-free catalyst leads to 3–4 times higher oxygen contents within the hydrogen product gas. This can be explained with a lower activity concerning oxygen recombination, so that less permeated oxygen is consumed and consequently, the oxygen flux within hydrogen is higher.」