pH‐Responsive Nanoporous Silica Colloidal Membranes

Abstract

Abstract Free‐standing colloidal membranes (nanofrits) with varied thickness and nanopore size are fabricated and modified with pH‐responsive poly(2‐(dimethylamino)ethyl methacrylate) brushes. The polymer‐modified nanofrits demonstrate excellent gating behavior for molecular diffusion: in the presence of acid, the diffusion rate of positively charged species significantly decreases. Increasing the polymer length and membrane thickness and decreasing the nanopore size leads to the complete acid‐controlled gating of the membranes.