One challenge remaining in the development of Ir-based electrocatalyst is the activity-stability paradox during acidic oxygen evolution reaction (OER), especially for the surface reconstructed IrO_x catalyst with high efficiency. To address this, a phase selective Ir-based electrocatalyst is constructed by forming bridged W-O moiety in NiIrO_x electrocatalyst. Through an electrochemical dealloying process, an nano-porous structure with surface-hydroxylated rutile NiWIrO_x electrocatalyst is engineered via Ni as a sacrificial element. Despite low Ir content, NiWIrO_x demonstrates a minimal overpotential of 180 mV for the OER at 10 mA·cm⁻². It maintains a stable 300 mA·cm⁻² current density during an approximately 300 h OER at 1.8 V_RHE and shows a stability number of 3.9 × 10⁵ n_oxygen · n_Ir⁻¹. The resulting W – O–Ir bridging motif proves pivotal for enhancing the efficacy of OER catalysis by facilitating deprotonation of OER intermediates and promoting a thermodynamically favorable dual-site adsorbent evolution mechanism. Besides, the phase selective insertion of W-O in NiIrO_x enabling charge balance through the W-O-Ir bridging motif, effectively counteracting lattice oxygen loss by regulating Ir-O co-valency.

Hydrogen is a favored alternative to fossil fuels due to the advantages of cleanliness, zero emissions, and high calorific value. Large‐scale green hydrogen production can be achieved using proton exchange membrane water electrolyzers (PEMWEs) with utilization of renewable energy. The porous transport layer (PTL), positioned between the flow fields and catalyst layers (CLs) in PEMWEs, plays a critical role in facilitating water/gas transport, enabling electrical/thermal conduction, and mechanically supporting CLs and membranes. Superior corrosion resistance is essential as PTL operates in acidic media with oxygen saturation and high working potential. This paper covers the development of high‐performance titanium‐based PTLs for PEMWEs. The heat/electrical conduction and mass transport mechanisms of PTLs and how they affect the overall performances are reviewed. By carefully designing and controlling substrate microstructure, protective coating, and surface modification, the performance of PTL can be regulated and optimized. The two‐phase mass transport characteristics can be enhanced by fine‐tuning the microstructure and surface wettability of PTL. The addition of a microporous top‐layer can effectively improve PTL|CL contact and increase the availability of catalytic sites. The anticorrosion coatings, which are crucial for chemical stability and conductivity of the PTL, are compared and analyzed in terms of composition, fabrication, and performance.

An in situ surface reconstruction method was developed to boost the activity of a Ni-based perovskite hydroxide for OER catalysis.