Graphene oxide gas separation membranes intercalated by UiO-66-NH2 with enhanced hydrogen separation performance

UiO-66-NH2 were either intercalated into graphene oxide (GO) layers (GOU@S) or covered by GO layers (GO/U@S) to form UiO-66-NH2/GO composite membrane. Results show that different synthesis methods would lead to different membrane morphology, thickness and gas separation performance. For GOU@S membrane, UiO-66NH(2) was well-dispersed and intercalated into GO layer, whereas two continuous layers (GO and UiO-66layer) with an obvious boundary were observed for GO/U@ S. Due to the morphology and structure difference, better hydrogen separation performance was achieved for GOU@S membrane compared to GO/U@ S membrane and pristine membrane due to the close interfacial contact between UiO-66-NH2 and GO, which arises from the hydrogen bonding formed between -NH2 group in UiO-66-NH2 and -OH group in GO and the electrostatic force between UiO-66-NH2 and GO layers. The ideal selectivities of H-2/N-2 and H-2/CO2 were increased to 9.75 and 6.35, respectively, for the GOU@S membrane with a H-2 permeance of 3.9 x 10(-8) mol m(-2) s(-1) Pa-1.