Mass transport losses ultimately suppress gas evolving electrochemical energy conversion technologies, such as fuel cells and carbon dioxide electrolyzers, from reaching the high current densities needed to realize commercial success. In this work, we reach ultrahigh current densities up to 9 A/cm² in a polymer electrolyte membrane (PEM) water electrolyzer with the application of custom porous transport layers (PTLs) with patterned through-pores (PTPs), and we reduce the mass transport overpotentials of the electrolyzer by up to 76.7 %. This dramatic performance improvement stems from the 43.5 % reduction in gas saturation at the catalyst layer-PTL interface region. Moreover, the presence of PTPs leads to more rapid bubble coalescence and subsequently more frequent bubble snap-off (∼3.3 Hz), thereby enhancing the rate of gas removal and liquid water reactant delivery to the reaction sites. This work is highly informative for designing PTLs for optimal gas removal for a wide range of gas evolving electrochemical energy conversion technologies.

中文翻译：

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带有图案化通孔的多孔传输层中的气泡分离加速

大量运输的损失最终抑制了诸如燃料电池和二氧化碳电解器之类的不断发展的气体电化学能转化技术，无法达到实现商业成功所需的高电流密度。在这项工作中，我们达到了高达9 A / cm ^2的超高电流密度在聚合物电解质膜（PEM）水电解槽中应用定制的具有图案化通孔（PTP）的多孔传输层（PTL），我们将电解槽的质子传输过电势降低了多达76.7％。这种显着的性能提高是由于催化剂层-PTL界面区域的气体饱和度降低了43.5％。此外，PTP的存在会导致气泡更快地聚结，并随后导致更频繁的气泡折断（〜3.3 Hz），从而提高了气体去除率和液态水反应物输送到反应部位的速度。这项工作对于设计PTL来为广泛的气体演化电化学能转换技术提供最佳的气体去除效果非常有用。