Synchronous Size and Electronic Structure Engineering of Atomic Cobalt Sites within Interlayer-Confined MoS2 Membrane for Enhanced Pollutants Degradation via Peroxymonosulfate Activation

Metal atomic cluster (AC) catalysts exhibit remarkable catalytic activity in environmental catalysis owing to their tunable structural and electronic properties regulated by electronic metal-support interactions (EMSI). Nevertheless, the precise size control of metal AC remains challenging owing to their inherent aggregation tendency under harsh synthetic conditions. Herein, we propose a confined synthesis strategy for fabricating cobalt AC within the interlayer channels of a two-dimensional molybdenum disulfide membrane (CoAC@MoS 2 membrane) for peroxymonosulfate (PMS) activation. The interlayer confinement of MoS 2 nanosheets enforces the in-plane assembly of metal precursors, yielding ultrafine CoAC (2.1 nm) with excellent Fenton-like activity (0.733 min -1 ), outperforming unconfined Co nanoparticles (29.3 nm, 0.291 min -1 ). Experiments and density functional theory calculations reveal that electrons transfer from sulfur vacancy and Mo sites in MoS 2 to Co 3d orbitals, generating electron-rich Co sites with an upshifted d -band center, which optimizes PMS adsorption and electron transfer to generate SO 4 ⚫- and ⚫OH radicals. The as-prepared CoAC@MoS 2 membrane achieved a sulfamethoxazole degradation rate of 5.33 × 10 6 μmol g metal -1 s -1 , which was 1-2 orders of magnitude higher than state-of-the-art nanoconfined catalytic membranes, and also proved effective in treating secondary pharmaceutical wastewater. This work establishes a universal paradigm for size and electronic structure engineering of metal catalysts through spatial confinement, advancing the development of high-performance Fenton-like catalytic systems for sustainable water remediation.