Proton exchange membrane water electrolysis (PEMWE) is currently limited by the sluggish kinetics and poor durability of the oxygen evolution reaction (OER). In this work, a structurally uniform IrB_160-4 catalyst was synthesized through a simple, scalable one-pot aqueous method. This template-free method enables near-quantitative yields and gram-scale preparation, with products rapidly separated via simple filtration. The catalyst consists of uniform, nanoclusters self-assembled from highly crystalline ~3 nm Ir nanoparticles. The optimized catalyst exhibits superior OER activity over commercial Ir-Black. The assembled proton exchange membrane electrolyzer, utilizing a low anodic iridium loading of 0.5 mg cm⁻², demonstrates excellent performance (2.0 A cm⁻² @ 1.79 V) and high durability (>1500 h). This synthesis strategy provides a feasible method for achieving efficient and stable PEM water electrolysis for hydrogen production.

Lattice strain engineering, rooted in symmetry-breaking lattice distortion, is an effective strategy for modulating the electronic structure and catalytic performance of electrocatalysts. Herein, non-noble metal CuCoNiCrMo_x high-entropy carbides with tunable Mo content (HEC_Mo-x) were rapidly synthesized within seconds via a high-temperature shock method. By leveraging composition-dependent lattice distortion engineering to deliberately break local translational symmetry, these catalysts were developed to optimize the alkaline hydrogen evolution reaction (HER). Density functional theory calculations reveal that lattice distortion optimizes the d-band center and regulates the electronic configuration. Concurrently, kinetic isotope effect tests and variable-potential electrochemical impedance spectroscopy measurements verify that this modulation balances the reaction kinetics of water dissociation and hydrogen adsorption, thereby accelerating the alkaline HER process. Consequently, the optimized HEC_Mo-15% electrocatalyst exhibits outstanding activity, requiring an overpotential of only 34 mV at 10 mA cm⁻². Furthermore, it exposes abundant active sites and maintains long-term operational stability with negligible attenuation over 23 h. This work provides a feasible design strategy and a practical paradigm for developing non-noble metal high-entropy carbides as highly efficient electrocatalysts for energy conversion applications.