Au cluster adsorption on perfect and defective MoS₂ monolayers: structural and electronic properties

Abstract

The adsorption of Au (n = 1-4) clusters on perfect and defective MoS monolayers is studied using density functional theory. For the pristine MoS monolayer, our results show that the electrons are transferred from the support to the adsorbed Au clusters, thus a p-doping effect is achieved in the pristine MoS monolayer by the Au cluster adsorption, which is in good agreement with the experimental findings. The adsorption of Au clusters can introduce mid-gap states, which modify the electronic and magnetic properties of the systems. The adsorbates containing an odd number of Au atoms can introduce a spin magnetic moment of 1 μ into the perfect MoS monolayer, while those systems containing an even number of Au atoms are spin-unpolarized. Two categories of defects, i.e., a single S vacancy and Mo antisite defect with one Mo atom replacing one S atom, are considered for the defective monolayer MoS. Compared with the pristine MoS monolayer, the adsorption energies for Au clusters are significantly increased for the MoS monolayer with a single S vacancy, and there are more electrons transferred from the MoS monolayer with an S vacancy to the Au clusters. The mid-gap states and odd-even oscillation magnetic behavior can also be observed when Au clusters are adsorbed on the MoS monolayer with an S vacancy. For those systems of Au clusters on MoS monolayers with Mo antisite defects, the adsorption energies as well as the magnitude and the direction of transferred charge are similar to those for the MoS monolayer with an S vacancy. The spin-polarizations appear in all systems with Mo antisite defects. Our investigations suggest that the electronic and magnetic properties of MoS nanosheets can be effectively modulated by the adsorption of Au clusters.

Inorganic molecule (O2, NO) adsorption on nitrogen- and phosphorus-doped MoS2 monolayer using first principle calculations

“…[13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] The length of the N-O bond of 1.17Å remains the same as that in the isolated NO molecule in the gas phase, which shows good agreement with the reported values. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] Here, it is also important to compare the adsorption energy of an NO molecule on a pristine monolayer graphene. The adsorption energies are (À0.03 and À0.12 eV), 41 which is signicantly smaller than that on the pristine MoS 2 monolayer.…”

“…[15][16][17] Similar to the case of graphene, dopants can play a key role in tuning the electronic structure properties and chemical reactivity of monolayer MoS 2 . [18][19][20][21] Moreover, various defects can be induced in MoS 2 , as conrmed from previous experiments and theoretical calculations. [22][23][24] Molecular doping at sulfur vacancies can be introduced reliably by electron irradiation, which provides an efficient way to tailor the properties of MoS 2 .…”

Rh-doped MoSe2 as a toxic gas scavenger: a first-principles study

“…For static electronic structure calculations, a selfconsistent loop energy of 10 À6 Ha, global orbital cut-off radius of 5.0Å and smearing of 0.005 Ha were employed to ensure the accurate results of total energy. 42 For basis set superposition errors (BSSE), little impact could be caused in the Dmol 3 package, 43 and thus we would not analyze it in the following part.…”

Adsorption and Sensing Behaviors of Pd-Doped InN Monolayer upon CO and NO Molecules: A First-Principles Study

“…Moreover, the electron hybridization during charge-transfer can support the activation of molecular orbitals as well [39], and it therefore could account for the change in the electronic behavior of the whole system. One can see that there are somewhat hybridization between Pd 4d and C 2p orbitals around −3-0 and 3 eV, which verifies the formation of chemical bonds due to the orbital interaction [40,41].…”