The MPL sits between the catalyst layer (CL) and porous transport layer (PTL), regulating water and gas flow. It ensures even water distribution, helps oxygen bubbles detach efficiently, and supports thin membranes, boosting overall efficiency and durability.
What is a microporous layer (MPL)?
Within a PEM electrolyzer, the MPL sits between the catalyst layer (CL) and porous transport layer (PTL), forming a controlled network of micro-scale pores. It is designed to regulate water and gas movement within the electrochemical cell. As PEM electrolyzer technology evolves, the role of an MPL has grown. Today, an MPL is a critical enabler of thinner membranes, lower precious-metal catalyst loadings, and higher current density operation.
