Adaptive metal–organic frameworks with crystalline dynamicity for durable gas separation

Dynamic chemistry offers opportunities for the design of smart materials that can self adapt or self repair to mediate their functionality. However, achieving anti-crack toughness using dynamic covalent bonds is often overlooked in crystalline porous solids such as metal–organic frameworks. Here we propose that crystalline dynamicity can be derived from bio-inspired disulfide metathesis, as demonstrated by a dynamic combinatorial library of isomeric metal–organic frameworks (LIFM-105, LIFM-105i, and LIFM-105a). Sulfur–sulfur bond breakage and regeneration facilitate stimuli-responsive interconversion between two-dimensional and three-dimensional frameworks, involving simultaneous layer rotation, component shift and linkage reorganization. The disulfide exchange-based crystal dynamics provides these porous solids with gas-induced adaptiveness and the gate effect, enabling pore tuning for efficient removal of C 2 H 2 from C 2 H 4 . Additionally, the guest-adaptation-motivated restoration and reorganization of the ‘damaged’ frameworks afford a promising protocol to apply radical-mediated dynamic solids as adaptive porous materials for durable separation and other applications.