Fig. 2: Pore structures and ion conduction.
a, N2 adsorption at 77 K. Four typical samples: PIM-1, AO-PIM-1, AO-PIM-1-Et, AO-PAN. P, equilibrium pressure; P0, saturation pressure. b, CO2 adsorption at 273 K. Four typical samples: AO-PIM-1, AO-PIM-1-De, AO-PIM-1-Et, AO-PAN. c, Water vapour adsorption isotherms as a function of relative humidity at 25 °C (solid symbols: adsorption; open symbols: desorption). AO-PIM-1, AO-PIM-1-De, AO-PIM-1-Et and PIM-1. d, Pore size distribution of hydrated polymers derived from computational models, measured by a 1 Å diameter probe. dV, pore volume; d(logW), pore width. e–h, Computational models of chain segments, water molecules bound to hydrophilic groups and hydrated polymer models for AO-PAN (e), AO-PIM-1 (f), AO-PIM-1-De (g) and AO-PIM-1-Et (h). The size of amorphous cells are: 53.8 Å (AO-PAN), 52.3 Å (AO-PIM-1), 56.5 Å (AO-PIM-1-De) and 53.7 Å (AO-PIM-1-Et). Colour of atoms and ions: red—oxygen; blue—nitrogen; grey—carbon; white—hydrogen; purple—lithium ions. i, Largest pore size and dynamic pore gate size, derived from hydrated polymer models. The data are presented as the mean ± s.d. (n = 10); the error bars represent the standard deviation (s.d.). j, Water self-diffusion coefficients versus the dynamic pore gate size derived from computational models. The water self-diffusion coefficients were probed by PFG-NMR and neutron scattering and calculated by MD simulation, respectively. k, Ionic conductivity as a function of hydrated diameter of salt ions, measured experimentally in 0.1 M KCl, 0.1 M NaCl, 0.1 M, LiCl and 0.1 M MgCl2 at 30 °C. The data are presented as the mean ± s.d. (n = 3); the error bars represent the standard deviation (s.d.). l, Temperature dependence of ionic conductivity of pretreated and pristine AO-PIM-1 membranes measured experimentally in 0.1 M NaCl solution. T, temperature.
