▎ 摘　　要

Graphene oxide (GO)-based membranes have been widely studied for various separation applications, but it is highly desirable to tailor their structure for the separation of small molecules such as hydrogen. Herein, we demonstrate the fabrication of a thin GO membrane by using a low-cost and highly gas permeable glass fiber (GF) filter as a porous substrate. By partial thermal reduction of GO, the interlayer channel size of the GF-supported GO membrane is precisely tailored for molecular sieving, leading to extraordinarily enhanced hydrogen sepa-ration performance. With the synergistic effect of retained functional-group interactions, the quasi-reduced GO (q-rGO) membrane displays a H2 permeance of 783 +/- 50 gas permeance units (GPU) and an impressive H2/CO2 separation factor as high as 3636 +/- 312, which is the highest selectivity for H2/CO2 reported thus far. In addition, the q-rGO membrane exhibits excellent durability with no performance degradation during a 120-h test. Our results represent a key step toward GO membrane-based molecular sieving applications.