nanosheets

Nanosheets are ultrathin two-dimensional nanomaterials with thickness in the nanometer range and substantially large lateral dimensions. They are typically one to several atomic layers thick, yielding high specific surface area and anisotropic properties that differ from bulk materials. They can be metallic, semiconducting, or insulating, with properties tunable by thickness, composition, and surface chemistry. Common examples include graphene nanosheets, transition metal dichalcogenide nanosheets (such as MoS2 and WS2), inorganic oxide nanosheets (like silica and alumina), clay nanosheets, and MXene nanosheets.

Synthesis methods span top‑down and bottom‑up approaches. Top‑down methods begin with bulk layered materials and produce thinner sheets via mechanical exfoliation, chemical intercalation followed by exfoliation, or liquid‑phase exfoliation. Bottom‑up strategies build sheets directly from precursors, including chemical vapor deposition and solvothermal synthesis. MXenes are typically produced by selectively etching elements from MAX phases followed by delamination.

Applications are diverse: electronics and optoelectronics (transistors, flexible electronics, photodetectors), energy storage and conversion (batteries, supercapacitors, electrocatalysis), catalysis and sensing, as well as membranes and coatings. Challenges include preventing restacking, achieving scalable production with uniform thickness, controlling defects, and ensuring stability and compatibility with devices.