a Single gas permeation with the one-?m-thick g-C3N4 membrane at place temperature and 1??bar. The inset shows the fuel selectivity for H2 around other gases. b Permeance and separation aspects on the one-?m-thick g-C3N4 membranes within the equimolar mixed-fuel permeation at home temperature and one??bar. Inset demonstrates the kinetic diameters o