▎ 摘　　要

Cellulose-based mixed-matrix membranes containing polyethylenimine-modified graphene oxide (PEI-GO) and Zn2+ ions were fabricated and used for gas separation. The incorporation of PEI-GO effectively hinders the crystallinity of regenerated cellulose, and PEI-GO was compatible with cellulose matrix and uniformly distributed within the matrix. X-ray photoelectron spectrum revealed the amino group on GO surface can effectively coordinate with Zn2+ ions in the membrane. The Zn2+ ions content in the membranes increased when increasing the PEI-GO addition. The optimum separation performance was achieved over the membrane with 17 wt parts per thousand PEI-GO (RC-17) wiht the highest zinc content of 24.2 wt%. The corresponding permeability of CO2 is as high as 268.9 Barrer, and the CO2/N-2 and CO2/CH4 ideal selectivities could reach 48.9 and 57.4, respectively. The enhancement of CO2 transportation was attributed to both the regulated microstructure of cellulose membrane by PEI-GO and the pi-complexation mechanism of Zn2+ ions with CO2 molecules. The prepared membranes would have a highly potential use in the field of CO2 separation.