A porous molecularly woven fabric for dynamic separation of water isotopologues

Heavy water (D2O) is a crucial strategic resource, but its low natural abundance (~0.015%) makes high-purity extraction challenging. The near-identical physicochemical properties, including comparable sizes and chemical characteristics, of H2O and D2O mean traditional separation methods are energy-intensive, underscoring the demand for more efficient alternatives. Porous materials such as metal–organic frameworks and covalent organic frameworks are promising for non-thermal separation. However, the realization of dynamic co-adsorption separation, wherein isotopologue mixtures are propelled through material columns under pressure, has not been achieved despite its desirability for practical applications. Here we report a porous molecularly woven fabric with a three-dimensional weaving network for successful dynamic separation of water isotopologues H2O and D2O. It is constructed through the mortise-and-tenon stacking of two-dimensional molecularly woven layers. Its woven channels provide transport pathways, while its adaptive woven and mortise-and-tenon nodes enhance adaptive adsorption, amplifying the subtle differences between these two isotopologues during the breakthrough process. Consequently, the porous woven network enables efficient dynamic separation of H2O and D2O at 298 K through its topological features. The low natural abundance of heavy water makes high-purity extraction challenging. Here, a porous molecularly woven fabric is constructed that features adaptive pores enabling the efficient dynamic separation of water isotopologues at room temperature (298 K).