Abstract
Two-dimensional carbide MXenes (Ti3C2Tx and V2CTx) were prepared by exfoliating MAX phases (Ti3AlC2 and V2AlC) powders in the solution of sodium fluoride (NaF) and hydrochloric acid (HCl). The specific surface area (SSA) of as-prepared Ti3C2Tx was 21 m2/g, and that of V2CTx was 9 m2/g. After intercalation with dimethylsulfoxide, the SSA of Ti3C2Tx was increased to 66 m2/g; that of V2CTx was increased to 19 m2/g. Their adsorption properties on carbon dioxide (CO2) were investigated under 0–4 MPa at room temperature (298 K). Intercalated Ti3C2Tx had the adsorption capacity of 5.79 mmol/g, which is close to the capacity of many common sorbents. The theoretical capacity of Ti3C2Tx with the SSA of 496 m2/g was up to 44.2 mmol/g. Additionally, due to high pack density, MXenes had very high volume-uptake capacity. The capacity of intercalated Ti3C2Tx measured in this paper was 502 V·v–1. This value is already higher than volume capacity of most known sorbents. These results suggest that MXenes have some advantage features to be researched as novel CO2 capture materials.