Comparative Study of Internal Mechanical Stresses in the Structures of Montmorillonite and Halloysite

Obtaining nanoscale tubes and scrolls is of fundamental and practical interest for science. In this study, the ability of montmorillonite and halloysite monolayers to curl into nanoscale scrolls is investigated using the electron density functional theory method on the example of studying the internal mechanical stresses in them. As a result of the study, it is revealed that mechanical stresses are present in both structures; however, they can be caused by the twisting of only the halloysite layers, due to the peculiarities of the structure. The mechanical stresses in montmorillonite are roughly double those in halloysite. However, the symmetrical structure of montmorillonite does not favor the formation of nanoscale scrolls and tubes, in contrast to the asymmetric structure of halloysite.