Tunable Dipole Moment in Janus Single-Layer MoSSe via Transition-Metal Atom Adsorption

Abstract

Intrinsic dipole moment is an important characteristic of Janus single-layer MoSSe. Tuning the dipole moment would broaden the potential applications of Janus MoSSe in the field of piezoelectricity and molecular sensing. In this study, the dipole moments of Janus single-layer MoSSe with 3d transition-metal (TM) adatoms (Sc–Ni) are explored by using first-principles calculations. Our results demonstrate that the dipole moments of Janus MoSSe change with TM atom adsorption. For the adsorption of TM atoms on the Se surface, the dipole moments are enhanced when compared to the case of pristine MoSSe, regardless of at the M adsorption site or at the H adsorption site. However, in the case of S surface adsorption, the dipole moments are weakened or even reversed for some TM atoms. Among all the 3d TMs considered, the effect of Sc atom adsorption is the largest, while it is the smallest for Ni atom adsorption. By means of a simplified model, the total dipole moments can be regarded as the superposition of the dipole moments from the Janus MoSSe and the ionic TM atoms. Strengthening and weakening of the dipole moments depend on the direction of dipole moments from the ionic TM atoms. Thus, we could utilize TM atom adsorption to tune the dipole moments with both magnitude and direction.

CO2 Capture, Separation and Reduction on Boron‐Doped MoS2, MoSe2 and Heterostructures with Different Doping Densities: A Theoretical Study

“…The results demonstrated that Mo−S and Mo−Se bond lengths of MoSSe monolayer were 2.41 and 2.53 Å, respectively. Our results are good consistent with the experimental and theoretical values [47,53,54] . In addition, Mulliken charges were performed to analyze the electronic properties of gas adsorption.…”

“…Our results are good consistent with the experimental and theoretical values. [47,53,54] In addition, Mulliken charges were performed to analyze the electronic properties of gas adsorption. It's worth noting that the calculational level is widely used for investigation of many reaction mechanisms.…”

Transition from Schottky to Ohmic contacts in Janus MoSSe/germanene heterostructures

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Strain Engineering and Electric Field Tunable Electronic Properties of Janus MoSSe/WX2 (X = S, Se) van der Waals Heterostructures

“…Jin et al found that Janus MoSSe is an ideal material for nanoscale sensors with high gas sensitivity and surface selectivity. Tao et al reported that the dipole moments of Janus MoSSe can be effectively tuned by applying transition‐metal atom adsorption. The S or Se defects in the Janus MoSSe monolayer can induce ferromagnetism and affect the catalytic performance .…”