Interactions between CO2 and clay minerals have attracted interest in the scientific community recently. This is partly motivated by the presence of large amounts of clays in caprock formations that act as flow barriers in storage sites for anthropogenic CO2. However, sorption mechanisms of carbon dioxide by clay minerals are not completely understood, and previous investigations are far from being complete and their results remain controversial. One of the hypotheses for the driving mechanisms of such process is the interaction between the gas and the residual H2O in the clay interlayer space. This interaction would affect (and maybe control) the kinetics of CO2 intercalation (and retention). To verify this hypothesis, we propose to perform QENS experiments to follow how the diffusivity of H2O is affected by in-situ capture of CO2 in the interlayer space of Li- and Ni-fluorohectorite.