Electronic and magnetic properties of structural defects in pristine ZrSe2 monolayer

Abstract

In the present study, we research the electronic and magnetic properties of structural defects in pristine ZrSe2 by using the first-principles methods based on density functional theory. Twelve cases of vacancy defects are considered by removing Zr, Se or Zr+Se atoms in pristine monolayer ZrSe2. In selecting vacancy defects, we consider the order of ascending defect concentration of Zr and Se, and also calculate the different relative positions of Se atoms with the same defect concentration of Se, compare the electronic and magnetic properties with them. The results show that vacancy defects in pristine ZrSe2 monolayer, which all induce to the increase of the total magnetic moment except V1Se. In addition, we find the total magnetic moment increases as the number of defective atoms increases in case of Se atoms vacancy defects, and the largest total magnetic moment appears on the case of V6Se. Moreover, we also found that almost all the vacancy defects in monolayer ZrSe2 show metallic property and ferromagnetism and total energies can be increased with the increasing of the number of vacant atoms in ZrSe2 monolayer. In particular, when the relative position of the defective atom changes, the total magnetic moment changes dramatically. In three cases of Zr atoms vacancy defects the lowest total energy is V1Zr, the most stable case is V1Se in the case of twelve vacancy defects we considered. Its vacancy-defect formation energy is 2.287 eV. These results have a few guiding significance for relevant experiments based on ZrSe2.