1.School of Materials Science and Engineering, Xi’an Jiaotong University , Xi’an 710049, China
2.Xi’an Filter Metal Materials Co., Ltd. , Xi’an 710201, China
Proton exchange membrane water electrolysis (PEMWE) is regarded as one of the most promising technologies for renewable energybased hydrogen production due to its high efficiency, rapid dynamic response and high-purity hydrogen output. However, the commercialization of PEMWE remains constrained by high costs and the need for performance optimization of critical materials. Among these, the porous transport layer (PTL), a core component in electrolyzers, plays a pivotal role in enhancing electrolyzer efficiency and durability through structural optimization. This review systematically examines the design, fabrication and performance optimization strategies of PTL, aiming to provide theoretical support and technical references for the development of high-performance PTL. The article details the primary fabrication processes for PTL and compares the characteristics of titanium powder-sintered PTL, titanium fiber-sintered PTL and composite-structured PTL. The influence of structural parameters, such as porosity, pore size distribution and thickness on conductivity, fluid permeability and bubble transport mechanisms is thoroughly explored. Furthermore, the necessity of optimizing the porous transport layer/catalyst layer (PTL/CL) interface is emphasized, with the introduction of a microporous layer highlighted as a critical approach to enhance the triplephase contact area and improve catalyst utilization. Finally, future research directions are summarized, including the optimization and cost reduction of PTL coating processes, the development of gradient microporous structures and composite architectures. This work is aimed at providing significant theoretical insights to advance the high efficiency and cost-effectiveness of PEMWE technology.