Predicting the structure and stability of oxide nanoscrolls from dichalcogenide precursors

Low-dimensional nanostructures such as nanotubes, nanoscrolls, and nanofilms have found applications in a wide variety of fields such as photocatalysis, sensing, and drug delivery. Recently, it was demonstrated that nanoscrolls of Mo and W transition metal oxides, which do not exhibit van der Waals (vdW) layering in their bulk counterparts, can be successfully synthesized using plasma processing of corresponding layered transition metal dichalcogenides. In this work, we employ data mining, first-principles simulations, and physio-mechanical models to theoretically examine the potential of other dichalcogenide precursors to form oxide nanoscrolls. By data mining bulk and two-dimensional materials databases, we first identify dichalcogenides that would be mostly amenable to plasma processing based on their vdW layering and thermodynamic stability. To determine the propensity for forming a nanoscroll, we develop a first-principles simulation-based physio-mechanical model to determine the thermodynamic stability of nanoscrolling as well as the equilibrium structure of the nanoscrolls, that is, their inner radius, outer radius, and interlayer spacing. We validate this model using experimental observations and find excellent agreement for the equilibrium nanoscroll structure. Furthermore, we demonstrate that the model’s energies can be utilized for a generalized quantitative categorization of nanoscroll stability. We apply the model to study oxide nanoscroll formation in MoS2, WS2, MoSe2, WSe2, PdS2, HfS2, and GeS2, paving the way for a systematic study of oxide nanoscroll formation atop other dichalcogenide substrates.