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The metal mask method is widely used for preparing diamond nanowires but has the problem of random structure distribution and inaccurate size control. This paper presents the first‐principle calculations for Al atoms' adsorption and migration behavior on diamond surfaces. The results show that the adsorption energy of Al atom is 0.2 eV, and the activation energy is 0.01 eV, resulting in the instability of the diamond/Al interface. The metal Al at the interface forms nanospheres at high temperatures. Similarly, its size and distribution depend on the diamond surface topography. Therefore, the anodic aluminum oxide template micro‐etching method is adopted to improve the metal mask preparation method and realize diamond nanoarrays' size and distribution control. [ABSTRACT FROM AUTHOR]

To explore the feasibility and rationality of a hydrogen‐terminated diamond surface film as an solid electrolyte interface (SEI) for lithium‐sulfur batteries, the adsorption and migration behavior of lithium atoms on the hydrogen‐terminated diamond surface with different amounts of hydrogen defects are determined by first‐principles calculations. Since a hydrogen deficiency in the row direction is denser than a hydrogen deficiency in the chain direction, hydrogen deficiency can drive lithium‐ion deposition. Thus, lithium atoms are more stable on the surface of hydrogen‐terminated diamonds with a hydrogen deficiency in the direction of the dimer row. The adsorption of lithium atoms on hydrogen‐terminated diamond films lacking three hydrogens is more stable due to the absence of dangling chemical bonds on the surface of the hydrogen‐terminated diamond. Therefore, lithium atoms cannot be adsorbed on an all‐H‐diamond surface. The low adsorption energy of lithium atoms on a clean diamond surface indicates that it is a simple physical adsorption. H termination increases the adsorption energy and migration activation energy of Li on the diamond surface. H termination changes the migration path of Li on the diamond surface. The atomic deposition of Li is driven by the center of the H defect region on the H‐diamond surface. [ABSTRACT FROM AUTHOR]

The surface structure and properties of aluminum nitride (AlN) play an important role in many applications. Using the first principle calculations method, we analyzed the surface terminal structure of AlN and its evolution under different conditions by determining the surface energy, adsorption energy, and evaporation energy of the Al and N terminals on the AlN(0001) surface. Our results show that the reason why the N terminal is less stable than the Al terminal is not only because of its high surface energy but also because its adsorption performance is extremely sensitive to the adsorption position. The surface N atoms combine to form N2 molecules that escape during the evaporation process at high temperature. After surface N atoms escape, the AlN surface structure reconstitutes to form a 3×3−R30° hexagonal closest packing (HCP)–like structure, and the energy barrier for the reconstructing process is 3.2 eV. This shows that the structure and form of the AlN(0001) terminals depend on the environmental conditions. [ABSTRACT FROM AUTHOR]

The transition metal‐related centers of diamond exhibit good properties. Herein, a first‐principles method based on density functional theory (DFT) is used to study single‐doped Ti‐related point defect structures and codoped structures of Ti and B or N, which possibly exist in diamond; the electronic structure and formation energy are also calculated. The results from structural calculations show that Ti is more likely to be located adjacent to a vacancy to form a TiV structure, which is more stable than other configurations. Ti doping introduces impurity levels into the pure diamond band gap, and the possible energy level transitions are determined. The results from the calculations of the codoped system show that the incorporation of N or B atoms is beneficial for the formation of defect structures and that the incorporation of N optimizes the energy band structure of the defects. When a substitutional Ti atom is located adjacent to a B atom and forms a Ti–B structure, and when four N atoms replace the corresponding neighboring C atoms around TiV to form a TiV–4N structure (which is similar to the NE8 configuration), the structure shows a better energy band structure, which presents new color centers. [ABSTRACT FROM AUTHOR]