LAUSR

Intercalation in bulk layered materials has been investigated intensively in the last 60 years. However, the rise of 2D few-layered nanomaterials such as transition metal oxides and chalcogenides opened up thrilling opportunities for the new era of intercalation as it is almost guaranteed that new phenomena will be observed with the intercalation of ions and molecules into few-layered nanomaterials due to the quantum confinement effect at the 2D scale. In this progress report, the advances of the 2D intercalation chemistry in the few-layered oxides and chalcogenides of molybdenum and tungsten are highlighted with respect to its concept, structure, implementation, identification, property modulation, and applications. The perspective and outlook concerning its current obstacles and future opportunities are addressed. The 2D intercalation chemistry in few-layered nanomaterials is still under its infant stage. The new intercalation phenomena behind the interlayer engineering of few-layered nanomaterials need to be discovered and further comprehensively exploited. It is strongly believed that with more attentions and efforts put into this spring field, the few-layered 2D nanomaterials will make great impact on the nanoscience and nanotechnology, enabling them more profound than their microstructural counterparts and even their monolayers.