Atomically Precise Core‐Tailoring Au _12‐ <i> _x </i> Ag <i> _x </i> ( <i>x</i> = 4, 5, 6) Nanoclusters for Enhanced Switchable Photocatalytic Therapy of Infected Wounds

ABSTRACT The development of structurally precise, efficient, and tunable metal nanocluster‐based photocatalysts serves as an ideal model for elucidating intrinsic reaction mechanisms. However, deciphering the correlation between individual metal atoms alterations in the metallic core and photocatalytic property modulation remains a formidable challenge. In this work, we employed an atomically precise synthesis strategy to design and tailor alloy clusters Au 12‐ x Ag x ( x = 4, 5, 6). Under light‐specific activation, these clusters efficiently catalyze oxygen to generate highly toxic reactive oxygen species (ROS), specifically hydroxyl radicals (·OH). The catalytic performance exhibiting composition dependence, achieving effective regulation of redox properties through gradient‐composition adjustments in the metal core. With increasing Ag atom incorporation, the photocatalytic capability of the alloy clusters is enhanced, exhibiting 99.9% broad‐spectrum antibacterial efficacy against both Gram‐positive and Gram‐negative bacteria. In infected murine models, nanocluster‐embedded wound dressings exhibited excellent biocompatibility and safety, enabling efficient and controllable photocatalytic antimicrobial action while mitigating excessive inflammation. The alloy clusters Au 12‐ x Ag x exhibit composition‐dependent properties, providing a good platform to investigate the relationship between structure and function at the atomic level.