Mechanically Tunable Néel Temperature in a 3D Nickel Oxide-Intercalated Muscovite Mesocrystal

Exploring the physical properties of functional materials in response to reduced-dimensional environments has attracted significant attention. In this study, we focus on the feature of van der Waals gaps in 2D layered silicate mica for intercalation. The van der Waals gaps between mica interlayers can be considered as 2D cavities, confining the growth direction of intercalants and resulting in controlled morphology and the fabrication of well-ordered 3D mesocrystal structures of NiO. In addition to the controlled morphology, Raman spectra further reveal Néel temperature of NiO can be modulated through mechanical bending in this ambient system. Furthermore, the NiO intercalants can be reduced to Ni metal under suitable thermodynamic conditions. This research introduces a strategy to control the intercalant and paves the way for tailoring the properties of nanomaterials for specific applications, establishing the concept of flexible 3D mesocrystals.