Two-dimensional non-van der Waals magnetic layers: functional materials for potential device applications

Two-dimensional (2D) magnetic materials have attracted extensive research attention in recent years due to their promising potential for use in nanoscale spintronic devices. Although most of them are synthesized by the mechanical exfoliation method from their layered bulk counterparts, due to their weak interlayer interactions, recently synthesized 2D non-van der Waals (non-vdW) ultrathin magnetic materials have revealed a novel direction for the discovery of 2D materials and the exploration of the corresponding applications. This review provides an overview of the recent progress in the non-vdW magnet family from the perspectives of both experimental and theoretical research. We first briefly introduce the synthesis methods and intrinsic properties of these non-vdW magnetic materials, and then summarize the electronic and magnetic properties available via doping/substitution, surface passivation, and heterostructure constructions. Promising research routes and challenges are also discussed at the end of the review. It is expected that this overview of 2D non-vdW magnets will provide guidelines for researchers in this field and inspire further exploration of new spintronic devices.