Oriented Two‐Dimensional Covalent Organic Framework Membranes with High Ion Flux and Smart Gating Nanofluidic Transport

Nanofluidic ion transport holds high promise in bio-sensing and energy conversion applications. However, smart nanofluidic devices with flux modulable capabilities remain to be realised. Herein, we demonstrate based on oriented two-dimensional covalent organic framework (2D COF) membranes vertically aligned nanochannel arrays that achieved a 2–3 orders of magnitude higher compared conventional single-channel devices. The surface-charge-governed conductance is dominant for electrolyte concentration up 0.01 M. Moreover, owing the customisable pH-responsivity imine phenol hydroxyl groups, COF-DT attained an actively pH-gating on/off ratio ≈100. structure rich chemistry COF materials will offer promising platform manufacturing modifiable ion/molecular features.