Confinement physical entanglement enables programmable polymeric mesoporous membranes from nanocrystal superlattices.

Mesoporous membranes with tunable architectures and robust mechanical properties remain challenging to fabricate, owing to the difficulty of simultaneously achieving structural order and mechanical stability. We report a general strategy to construct programmable polymeric mesoporous membranes by exploiting confined physical entanglement within polymer-grafted nanocrystal (NC) superlattices. Two-dimensional superlattices, self-assembled at the liquid-air interface from size-, shape-, and composition-controlled NCs, serve as structural templates, and thermal annealing activates polymer entanglement to stabilize the superlattice framework. Subsequent selective removal of NC cores yields free-standing, long-range-ordered polymeric mesoporous membranes that exhibit remarkable specific moduli and deformability. Importantly, this approach enables independent control over pore size, wall thickness, and pore symmetry, offering precise structural programmability beyond conventional templating methods. This strategy is compatible with a wide range of building blocks and binary superlattice configurations, enabling the rational design of mechanically robust mesoporous membranes with hierarchical structural order.