The electronic and magnetic properties of n- and p-type impurities by means of group V and VII atoms substituting sulfur in a MoS ₂ monolayer were investigated using first-principles methods based on density functional theory.

Using a first-principles method, based on the Vienna Ab-initio Simulation Package (VASP), we have studied the electronic structure, formation energy and transition level of a MoSe ₂ monolayer doped with V and VII atoms.

Graphene-based two-dimensional hybrid materials are attracting significant attention because they can preserve novel characteristics of Dirac cone. Here, based on first-principles methods, we focus on the electronic characteristics of PtSe ₂ /graphene hetero-multilayer. The negative binding energies indicate that the hybrid materials can be fabricated easily in practice. Also, the n-type Schottky contact is formed and its barrier height is robust to the number of graphene layer. Moreover, the gate-voltage can effectively induce the Schottky barrier transformation from n -type to p -type and contact type transformation from Schottky to Ohmic in the PtSe ₂ /graphene hetero-multilayer. Thus, the work demonstrates that the graphene stacking configuration and gate-voltage will tune the electronic characteristics of PtSe ₂ /graphene-based nanodevices.

In X(OH)₂/graphene (X = Ca, Mg) vdW heterostructures, the Schottky barrier height and contact types are effectively tuned by electric fields.

The future development of optoelectronic devices will require an advanced control technology in electronic properties, for example by an external electric field (E_field).