Hybrid 3D‐Ordered Membrane Electrode Assembly (MEA) with Highly Stable Structure, Enlarged Interface, and Ultralow Ir Loading by Doping Nano TiO2 Nanoparticles for Water Electrolyzer

Abstract Proton exchange membrane water electrolysis (PEMWE) is a very promising and sustainable hydrogen production technology. Currently, there is a growing interest in achieving ordered structures within membrane electrode assembly (MEA) for PEMWE. However, both ordered electron conductor and ordered proton conductor structures are single component structure, which still have many shortcomings. In this work, a hybrid ordered membrane electrodes assembly based on cone‐shaped is constructed Nafion array with rough surface by introducing TiO 2 nanoparticles to Nafion emulsion. As a result, this hybrid ordered MEA achieves a high surface roughness of 3.39 nm that is 2.64 times higher than that of ordered MEA without TiO 2 nanoparticles doped and current density up to 2.48 A cm −2 at 2 V with 14.4 µg cm −2 (Ir) catalyst loading. This work provides a new hybrid ordered structure for MEA and exhibits the great potential of enhancing the interfacial contact between the catalyst layer and Nafion membrane to improve PEMWE performance.