Suppression of material transfer at contacting surfaces: the effect of adsorbates on Al/TiN and Cu/diamond interfaces from first-principles calculations

Abstract

The effect of monolayers of oxygen (O) and hydrogen (H) on the possibility of material transfer at aluminium/titanium nitride (Al/TiN) and copper/diamond (Cu/C) interfaces, respectively, were investigated within the framework of density functional theory (DFT). To this end the approach, contact, and subsequent separation of two atomically flat surfaces consisting of the aforementioned pairs of materials were simulated. These calculations were performed for the clean as well as oxygenated and hydrogenated Al and C surfaces, respectively. Various contact configurations were considered by studying several lateral arrangements of the involved surfaces at the interface. Material transfer is typically possible at interfaces between the investigated clean surfaces; however, the addition of O to the Al and H to the C surfaces was found to hinder material transfer. This passivation occurs because of a significant reduction of the adhesion energy at the examined interfaces, which can be explained by the distinct bonding situations.

Mechanical properties of TiO2/carboxylic-acid interfaces from first-principles calculations

“…The value of 0.1 Å was found here and in previous studies, e.g. 28 for Al/TiN interfaces, to be a reliable choice. In the tensile region, this procedure is continued until the interface fails, which is automatically detected from a significant drop in the force.…”

A Combined Experimental and Theoretical Study on the Mechanisms Behind Tribocharging Phenomenon and the Influence of Triboemission

“…In order to simulate the variation of the distance between the two surfaces that occurs during sliding the two slabs were separated by moving the upper slab in discrete steps along the z direction and letting the system to relax after each step [43]. For the atomic relaxations the top two bi-layers of the C(111) and the SiO 2 atoms up to 3.45 Å in the z direction were kept fixed at bulklike distance, whereas the intermediate atoms were allowed to fully relax.…”

The Effects of Alloying Elements on the Bonding Strength of Diamond/Carbide/Cu Interface Based on First‐Principles Calculations

“…To further understand the electron transfer and bonding at the interface, we calculated the charge density difference at the interface. [41][42][43] As shown in Figure 6, yellow represents gaining electrons, and blue represents losing electrons. It can be found from Figure 6a,c that both Cu and Ti (Zr) at the interface lose electrons, participating in the charge accumulation at the interface and forming metallic bonds.…”