Enhancing Ferromagnetism and Tuning Electronic Properties of CrI Monolayers by Adsorption of Transition-Metal Atoms.

Among first experimentally discovered two-dimensional (2D) ferromagnetic materials, chromium triiodide (CrI) monolayers have attracted particular attention due to their potential applications in electronics and spintronics. However, the Curie temperature of the CrI monolayer is below room temperature, which greatly limits practical development of the devices. Herein, using density functional theory calculation, we explore how the electronic and magnetic properties of CrI monolayers change upon adsorption of 3d transition-metal (TM) atoms (from Sc to Zn). Our results indicate that the electronic properties of the TM-CrI system can be tuned from semiconductor to metal/half-metal/spin gapless semiconductor depending on the choice of the adsorbed TM atoms. Moreover, the adsorption can improve the ferromagnetic stability of CrI monolayers by increasing both magnetic moments and . Notably, of CrI with Sc and V adatoms can be increased by nearly a factor of 3. We suggest postsynthesis doping of 2D CrI by deposition of TM atoms as a new route toward potential applications of TM-CrI systems in nanoelectronic and spintronic devices.