Fig. 5

Results of SHAP analysis for (a) CO2 permeance and b CO2/N2 permselectivity. The top 3 significant features for CO2 permeance based on the mean absolute SHAP values are the degree of unsaturation in the organic groups (un), the amount of HCl catalyst (HCl), and the CO2 coordination energy (H), whereas those for CO2/N2 permselectivity are the operation temperature (temp), CO2 coordination energy, and the average distance between Si atoms (Si–Si). The other features are described in the Materials and methods section