Solvation Structure Regulated Intercalation Chemistry Enables Scalable and Oxidation‐Suppressed Monolayer MXenes

The scalable production of high‐quality monolayer MXenes is essential but remains challenging due to a persistent yield–quality dilemma during ion intercalation. Conventional hydrated lithium ions ([Li + (H 2 O) x ]) provide insufficient steric expansion to overcome interlayer interactions, resulting in limited monolayer yields, while the water molecules inevitably induce surface oxidation and compromise material quality. Herein, we report a universal Li + solvation structure regulation strategy to address this limitation. By leveraging the strong coordination of dimethyl sulfoxide (DMSO) to displace water, the enlarged and water‐deficient ([Li + (DMSO) x (H 2 O) y ]) supramolecular clusters are constructed. The tailored solvation structure simultaneously expands interlayer spacing and forms a hydrophobic interfacial barrier via electron‐transfer‐induced DMSO chemisorption, enabling a high monolayer yield of 95.4% while effectively suppressing oxidation. Importantly, this scalable protocol (100 g scale) exhibits broad applicability to challenging MAX precursors (e.g., Ti 3 AlCN and Ti 2 AlC), enabling the mass production of diverse oxidation‐resistant MXenes. The resulting films show excellent environmental stability and reliable performance in electromagnetic‐interference shielding and infrared thermal camouflage.