Structural, Electronic, and Mechanical Properties of 2D Oxidized Diamond (100) Nanofilms

Abstract

In this work, the structural, electronic, and mechanical properties of 2D atomically thick diamond (100) nanofilms with surface oxygen functionalization as a function of layer number (n) are investigated by first‐principles calculation. The phonon dispersion curves and ab‐initio molecular dynamics results prove the dynamical and thermal stabilities of the structures at n ≥ 6. The bandgaps of oxidized diamond nanofilms are independent of the layer number, attributed to the main contribution of surface atoms to conductance bands and valence bands near the Fermi energy. The Perdew–Burke–Ernzerhof (PBE) calculations with n from 6 to 22 show that the bandgaps of nanofilms with ether groups on both outmost sides (ether groups on one side and hydrogen functional groups on the other side) are in the region of 1.308–1.838 eV (1.803–1.884 eV). The bandgap values of nanofilms with methoxyacetone groups on both outmost sides (methoxyacetone groups on one side and hydrogen functional groups on the other side) localized in the region of 3.078–3.329 eV (3.135–3.302 eV), and the flat valence bands and conduction bands near the Fermi energy make the easy transition between direct to indirect bandgaps. The calculated elastic constants and acoustic velocities of nanofilms have a significantly parity‐dependent oscillatory phenomenon and increase with increasing film thickness. This work provides new ideas for fabricating 2D diamond‐based nanodevices (i.e., optoelectrical semiconductor devices, micro‐ and nano‐electro‐mechanical systems) with high performances applied in practical fields.

Diamane Oxide. Two-Dimensional Film with Mixed Coverage and a Variety of Electronic Properties

“…It is important to note that despite the successful synthesis of diamane by hydrogenation and fluorination processes, , in most papers, binding of graphene is associated with deposition of oxide groups on its surface. − In contrast to hydrogenated and fluorinated diamane, the structure of oxidized diamane has not been studied in detail yet. Only a limited number of works exist where relatively simple models are proposed. ,, This is an obstacle to further analysis and interpretation of the experimental data. The main problem is that graphene oxide (as well as diamane oxide) can be considered as a two-dimensional solid solution of different functional groups distributed on the graphene surface.…”