Freestanding Block Copolymer Membranes with Tunable Pore Sizes Promoted by Subnanometer Nanowires

Abstract

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.

Subnanometer Nanowire‐Reinforced Construction of COF‐Based Membranes with Engineering Biomimetic Texture for Efficient and Stable Proton Conduction

“…[41][42][43] Briefly, SNWs refer to nanowire materials with a diameter close to the size of single unit cell and show some polymer-analogue properties, such as high flexibility, conformational diversity, and viscosity because of the dimensional similarity with linear polymers. [44][45][46] The proportion of surface-exposed atomic in SNWs is near 100%, so their interaction with the external field is ultra-strong. More critically, the strong cohesion due to multi-level interactions within the SNWs results in a powerful anchoring of the POMs.…”

Versatile Organogels of Aluminum Oxide Subnanosheets for Locking Solvents and Adhesion

“…Subnanometer materials with sizes in the sub 1 nm scale exhibit entirely different properties from bulk or even classical nanomaterials. − Sizes comparable to those of single unit cells and macromolecules render subnanometer materials with high atomic ratios and abundant acting sites and in consequence polymer-analogue properties, such as flexibility, viscoelasticity, and processability. , Various subnanometer nanomaterials play promising roles in organogels, adhesive materials, mechanical materials, , polarization optical devices, battery materials, photothermal membranes, − chiral materials, and so on, which inspired the investigation of the original aluminum oxide subnanomaterials with versatile performance.…”