Lattice distortion strain modulation of twin-defective noble-metal-free high-entropy alloy electrocatalyst for Li−O2 batteries

Despite progress on noble-metal high-entropy alloy catalysts, noble-metal-free high-entropy alloy catalysts continue to face limitations in activity and stability. Atomic defect engineering holds promise for unlocking catalytic potential, yet efficient strategies for designing defects to simultaneously tailor electronic structures and enhance catalytic active sites in noble-metal-free high-entropy alloys remain challenging. Here, we report a general rule to drive twin formation via precisely tuning lattice strain in metallic nanomaterials. By modeling twin formation energy as a descriptor and employing a gradient-radius hetero-atomic doping strategy, we derive a generalized lattice strain-twin formation energy function that determines critical strain for twinning propensity. Guided by this principle, Ce is incorporated into CuCoNiMnMo nanoparticles, promoting coherent five-fold twinning along {111} planes. Twin boundaries generate high-activity sites by disrupting atomic symmetry and reducing coordination numbers, while modulating band width via altered orbital overlap. Meanwhile, strong Ce-O affinity forms an amorphous CeO x passivation layer on twinned noble-metal-free high-entropy alloy, triggering hetero-interfacial electron transfer. These effects synergistically optimize reaction kinetics. Consequently, the engineered catalyst achieves a 405-cycle lifespan in lithium–oxygen batteries and operates across −20 to 80 °C. Our study brings fundamental insights into defect engineering for electrocatalysis in energy conversion fields.