Sulfur‐Modified Amorphous Noble‐Metal‐Free High‐Entropy Alloy Ultra‐Thin Nanosheets for Low‐Overpotential and Long‐Lifespan Li‐O 2 Batteries

ABSTRACT While noble‐metal‐free high‐entropy alloys (NHEA) represent promising low‐cost catalysts for Li‐O 2 batteries, their catalytic capability is limited by the low metal‐site utilization and unfavorable electronic structure inherent in conventional configurations. Herein, we report a novel design for a CuFeCoNiMn‐NHEA catalyst, characterized by its entirely amorphous structure and the Metal─S bonds (especially Ni─S) introduced by S‐doping. The successful synthesis of this catalyst relies on a rapid low‐temperature strategy, where the 5°C reaction temperature limits atomic diffusion and long‐range ordering, while the sub‐1‐min duration kinetically traps the atoms in a disordered state. Within this architecture, the ultra‐thin 2D morphology, disordered atomic arrangement, and unsaturated atomic coordination offer abundant active sites by eliminating constraints from crystal planes and boundaries; simultaneously, the Metal─S bonds significantly optimize the electronic structure. The electronegativity gradient between metal and S induces electron delocalization at metal sites, which lowers the d‐band center and optimizes the adsorption energy of * LiO 2 intermediates, thereby accelerating the redox kinetics. Meanwhile, strengthened Metal─S coordination elevates metal vacancy formation energies by 1–3 times, which suppresses atomic leaching to improve structural stability. Therefore, our unique catalyst achieves a low overpotential (0.48 V), and an exceptional lifespan (452 cycles), significantly outperforming most reported noble‐metal‐free catalysts.