The unexpected effect of vacancies and wrinkling on the electronic properties of MoS2 layers

We report a combined experimental/theoretical approach to study the connection of S-vacancies and wrinkling on MoS₂ layers, and how this feature produces significant changes in the electronic structure and reactivity of this 2D material.

Adsorption and Desulfurization Mechanism of Thiophene on Layered FeS(001), (011), and (111) Surfaces: A Dispersion-Corrected Density Functional Theory Study

Layered transition-metal chalcogenides have emerged as a fascinating new class of materials for catalysis. Here, we present periodic density functional theory (DFT) calculations of the adsorption of thiophene and the direct desulfurization reaction pathways on the (001), (011), and (111) surfaces of layered FeS. The fundamental aspects of the thiophene adsorption, including the initial adsorption geometries, adsorption energies, structural parameters, and electronic properties, are presented. From the calculated adsorption energies, we show that the flat adsorption geometries, wherein the thiophene molecule forms multiple π-bonds with the FeS surfaces, are energetically more favorable than the upright adsorption geometries, with the strength of adsorption decreasing in the order FeS(111) > FeS(011) > FeS(001). The adsorption of the thiophene onto the reactive (011) and (111) surfaces is shown to be characterized by charge transfer from the interacting Fe d-band to the π-system of the thiophene molecule, which causes changes of the intramolecular structure including loss of aromaticity and elongation of the C-S bonds. The thermodynamic and kinetic analysis of the elementary steps involved in the direct desulfurization of thiophene on the reactive FeS surfaces is also presented. Direct desulfurization of thiophene occurs preferentially on the (111) surface, as reflected by the overall exothermic reaction energy calculated for the process (ER = -0.15 eV), with an activation energy of 1.58 eV.

Density functional study on the high catalytic performance of single metal atoms on the NbC(001) surface

We have studied the adsorption and electronic properties as well as the catalytic activities of group 9–11 single metal atoms deposited on NbC(001).

Synergistic effect of Mo2N and Pt for promoted selective hydrogenation of cinnamaldehyde over Pt–Mo2N/SBA-15

Pt–Mo₂N/SBA-15 exhibits high activity for selective hydrogenation of cinnamaldehyde due to the synergistic effect between Mo₂N and Pt.