Synthesis, characterization, and CO2 adsorption performance of UiO-66-(OH)2/GO composite

The flue gas produced by fossil fuel combustion contains a large amount of CO2, and the greenhouse effect caused by CO2 emissions is becoming increasingly serious. There is an urgent need to develop adsorbents with excellent CO2 adsorption performance. In this study, a new composite graphene oxide (GO) -metal-organic framework (MOF) (UiO-66-(OH)2/GO) was synthesized using UiO-66-(OH)2 as a precursor. Structural analysis of the parent materials and composites found that pore structures and Brunauer–Emmett–Teller (BET) surface area could be adjusted by adding GO, and GO was tested as a carbon dioxide adsorbent at 273 K and 298 K. The maximum CO2 adsorption of the composites was 5.03 mmol/g and 4.34 mmol/g, which was 36.7% and 36.9% higher than that of the parent materials at 1 bar, respectively. Dynamic breakthrough experiments were used to study the CO2/N2 separation capability of the composites. The stability of composites was studied by chemical stability experiments and several adsorption/desorption experiments. The results showed that the composites had good acid resistance and cycle stability. The separation performance of CO2/N2 in the presence of water vapor was investigated, and the composites showed good water stability. Therefore, UiO-66-(OH)2/GO has latent applications in CO2 capture technology to mitigate global warming.