Fig. 5: Hourglass-shaped nanochannels structure of COF-CDN membranes.
From: Covalent organic framework membrane with hourglass-shaped nanochannels for ultrafast desalination
a Protonated and b deprotonated states of the hourglass-shaped nanochannels. The colors of the atoms are represented as follows: gray for carbon (C), white for hydrogen (H), red for oxygen (O), blue for nitrogen (N), and green for positively charged nitrogen (N+). Channel sizes were calculated using Materials Studio simulation, with specific measurements provided in (a”) and (b”); c pH-responsive protonation-deprotonation transition behavior of the COF-CDN membranes.
