Experimental and theoretical study of the effect of different functionalities of graphene oxide/polymer composites on selective CO 2 capture

There is a constant need for versatile technologies to reduce the continuously increasing concentration of CO 2 in the atmosphere, able to provide effective solutions under different conditions (temperature, pressure) and composition of the flue gas. In this work, a combination of graphene oxide (GO) and functionalized waterborne polymer particles was investigated, as versatile and promising candidates for CO 2 capture application, with the aim to develop an easily scalable, inexpensive, and environmentally friendly CO 2 capture technology. There are huge possibilities of different functional monomers that can be selected to functionalize the polymer particles and to provide CO 2 -philicity to the composite nanostructures. Density functional theory (DFT) was employed to gain a deeper understanding of the interactions of these complex composite materials with CO 2 and N 2 molecules, and to build a basis for efficient screening for functional monomers. Estimation of the binding energy between CO 2 and a set of GO/polymer composites, comprising copolymers of methyl methacrylate, n-butyl acrylate, and different functional monomers, shows that it depends strongly on the polymer functionalities. In some cases, there is a lack of cooperative effect of GO. It is explained by a remarkably strong GO-polymer binding, which induced less effective CO 2 -polymer interactions. When compared with experimental results, in the cases when the nanocomposite structures presented similar textural properties, the same trends for selective CO 2 capture over N 2 were attained. Besides novel functional materials for CO 2 capture and a deeper understanding of the interactions between CO 2 molecules with various materials, this study additionally demonstrates that DFT calculations can be a shorter route toward the efficient selection of the best functionalization of the composite materials for selective CO 2 capture.