The intermolecular forces among volatile organic molecules are usually weaker than water, making them more difficult to absorb. We prepared alkaline earth cations–bridged polyoxometalate nanoclusters subnanometer nanowires through a facile room-temperature reaction. The nanowires can form three-dimensional networks, trapping more than 10 kinds of volatile organic liquids effectively with the mass fraction of nanowires as low as 0.53%. A series of freestanding, elastic, and stable organogels were obtained. We prepared gels that encapsulate organic liquids at the kilogram scale. Through removing solvents in gels by means of distillation and centrifugation, the nanowires can be recycled more than 10 times. This method could be applied to the effective trapping and recovery of organic liquids.

Block copolymers (BCPs) have enduring appeal for its intriguing assembly behaviors. Nevertheless, the unsatisfactory mechanical properties of BCPs make it a problem to fabricate freestanding membranes and hindered practical applications. Herein, a freestanding membrane with tunable pore size is prepared simply by co‐assembly of BCPs and subnanometer nanowires (SNWs), combining the abundant function of BCPs and prominent mechanical properties of SNWs. Benefited from synergy of the components and the hierarchical structure, the tensile strength of composite membrane is promoted by two orders of magnitude compared to that of BCPs. With the columnar pores aligning vertically to surfaces and the pore size regulated by processing conditions, the membranes exhibit precise size‐selected effect in ultrafiltration of Au nanoparticles (Au NPs) and can distinct NPs with diameter difference as tiny as 5 nm, demonstrating the promising prospect in separation technology and even widespread fields.