The platform effect of graphene oxide on CO2 transport on copper nanocomposites in ionic liquids

We report the effect of graphene oxide (GO) on a facilitated CO2 transport membrane consisting of copper nanoparticles (CuNP) prepared in situ in ionic liquids (IL), such as 1-hexyl-3-methylimidazolium nitrate (HmimNO3) and 1-methyl-3-octylimidazolium tetrafluoroborate (MoimBF4). The highly smooth surface of the GO was characterized by atomic force microscopy, and the interactions between the GO and the IL were investigated by Fourier transform-Raman spectroscopy. With GO, the fabricated HmimNO3/CuNP/GO and MoimBF4/CuNP/GO composite membranes showed CO2/N2 separations of 8.7 and 30.7, respectively, with enhanced CO2 gas permeance compared to IL/CuNP composite membrane without GO. This implies that graphene oxide can be used as an effective additive in nanocomposite membranes for enhanced CO2 permeance.