Physicochemical characterisation of fluorohectorite: Water dynamics and nanocarrier properties

The Impact of Thermal History on Water Adsorption in a Synthetic Nanolayered Silicate with Intercalated Li+ or Na+

“…The authors showed that the LiFHt powder received from the producer (Corning Inc.) contains about 20% by mass of impurities. This is confirmed in the XRD data, where Li 2 O·2SiO 2 (lithium disilicate–Li 2 Si 2 O 5 ), SiO 2 (quartz), and Mg­(OH) 2 (brucite) are identified phases in the sample, while brucite was also observed by Larsen et al…”

“…These rehydrated samples allowed us to quantify the initial amount of H 2 O in the clay mineral layers as well as to describe different hydration states. This procedure was also used in refs , , .…”

“…The interlayer cation plays an important role in the water adsorption process, , since water can form different H 2 O–cation complexes depending on the intrinsic charge and ionic radius of the cation, which can significantly change the water adsorption properties. An increase in the layer charge will result in an increase in the number of interlayer cations, but this can also cause a decrease in the interlayer distance and consequently can make the clay material more hydrophobic. , Additionally, it is well established that the dissimilarities in H 2 O uptake and loss between different smectites are related to the manner in which the intercalated cation changes the H-bond network around H 2 O molecules. , …”

“…For clay swelling related applications, it is of paramount importance to understand how the interaction between water and clay minerals results in hysteresis in the adsorption process, since in nature or in industrial processes, these materials are rarely found without water. Consequently, over the years, several studies have been dedicated to better understanding this phenomenon. , The explanations range from structural rearrangements in the clay, which changes the water diffusion coefficient, ,,, to changes in the layers during swelling or shrinkage, which is attributed to a phase transition between hydration states. , Hsiao and Hedström concluded that processes occurring outside of the interlayer structure must be considered since traces of hysteresis in the interlayer space could not be found, while Gates et al performed an in situ QENS experiment and found that rehydrated clay adsorbs less water, thus confirming that water adsorption is hysteretic.…”

Experimental methods to study clay minerals and perspective applications of Fluorohectorite

“…All-in-all the very active ongoing scientific work on natural [140,141] and/or synthetic [142,143] , including FHt [144,145,146,147] , and in particular on FHt-B, should extend dramatically the mentioned applications and hint to new ones. FHt is an important material in clay science that definitely underlines the statement that "clays may be considered the material of the 21 st century" [8] .…”