Microscopic Mechanism For Enhancing the Optoelectronic Performance of B and P-Doped MoS2/Gr Heterojunctions Based on Density Functional Theory
To extend the theory related to new composite materials that can enhance the performance of optical modulators,the modulation mechanism of the optoelectronic properties of B-doped and P-doped MoS2/Gr heterojunctions is investigated.The results show that after the formation of the heterojunction,there is an electron transfer from the graphene layer to the surface of the MoS2 layer between the heterojunction layers;after the doping of atoms,the electrons transferred between the graphene and molybdenum disulfide layers of the heterojunction are redistributed,and the electron transfer from the B atom to the C atom,the P atom to the S atom,and between the B atom and the P atom mainly occurs,leading to the phenomenon of electron aggregation between the layers near the doped P atom.Near the Fermi energy level,orbital hybridization between the dopant atoms and graphene and molybdenum disulfide occurs,resulting in a narrower energy gap for carrier jumps,leading to enhanced interaction with light in the low energy region in the near-infrared and even below,and some optical absorption peaks move towards the low energy region,the modulation of the optical properties in the low-energy region of the heterojunction can be achieved to some extent by changing the concentration and ratio of doped atoms.