TY - JOUR AU - Neupane, Hari Krishna AU - Adhikari, Narayan Prasad PY - 2021/04/17 Y2 - 2024/03/29 TI - Electronic and magnetic properties of defected MoS2 monolayer JF - BIBECHANA JA - BIBECHANA VL - 18 IS - 2 SE - Research Articles DO - 10.3126/bibechana.v18i2.33905 UR - https://www.nepjol.info/index.php/BIBECHANA/article/view/33905 SP - 68-79 AB - <p>It is interesting to understand the effect of defects in 2D materials because vacancy defects in 2D materials have novel electronic and magnetic properties. In this work, we studied electronic and magnetic properties of 1S vacancy defect (1S<sub>v</sub>-MoS<sub>2</sub>), 2S vacancy defects (2S<sub>v</sub>-MoS<sub>2</sub>), 1Mo vacancy defect (Mo<sub>v</sub>-MoS<sub>2</sub>), and (1Mo &amp; 1S) vacancy defects ((Mo-S)<sub>v</sub>-MoS<sub>2</sub>) in 2D MoS<sub>2 </sub>material by first-principles calculations within spin-polarized density functional theory (DFT) method. To understand the electronic properties of materials, we have analyzed band structures and DOS calculations and found that 1S<sub>v</sub>-MoS<sub>2 </sub>&amp; 2S<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials have semiconducting nature. This is because, 1S<sub>v</sub>-MoS<sub>2 </sub>&amp; 2S<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials open a small energy band gap of values 0.68 eV &amp; 0.54 eV respectively in band structures. But, in Mo<sub>v</sub>-MoS<sub>2 </sub>&amp; (Mo-S)<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials, energy bands around the Fermi level mix with the orbital’s of Mo and S atoms. As a result, bands are split and raised around and above the Fermi energy level. Therefore, Mo<sub>v</sub>-MoS<sub>2 </sub>&amp; (Mo-S)<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials have metallic nature. We found that MoS<sub>2</sub>, 1S<sub>v</sub>-MoS<sub>2 </sub>&amp; 2S<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials have non-magnetic properties, and Mo<sub>v</sub>-MoS<sub>2 </sub>&amp; (Mo-S)<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials have magnetic properties because magnetic moment of MoS<sub>2</sub>, 1S<sub>v</sub>-MoS<sub>2 </sub>&amp; 2S<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials have 0.00 µ<sub>B</sub>/cell value and Mo<sub>v</sub>-MoS<sub>2 </sub>&amp; (Mo-S)<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials have 2.72 µ<sub>B</sub>/cell &amp; 0.99 µ<sub>B</sub>/cell &nbsp;respectively. Therefore, non-magnetic MoS<sub>2 </sub>changes to magnetic Mo<sub>v</sub>-MoS<sub>2 </sub>&amp; (Mo-S)<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials due to Mo and (1Mo &amp; 1S) vacancy defects.&nbsp; The magnetic moment obtained in Mo<sub>v</sub>-MoS<sub>2 </sub>&amp; (Mo-S)<sub>v</sub>-MoS<sub>2</sub>&nbsp;materials due to the distribution of up and down spins in 4p, 4d &amp; 5s orbitals of &nbsp;Mo atoms and 3s &amp; 3p orbitals of S atoms in structures. The significant values of the magnetic moment are given by distributed spins in 4d orbital of Mo atoms and 3p orbital of S atoms.</p><p>BIBECHANA 18 (2) (2021) 68-79</p><p>&nbsp;</p> ER -