Tailoring intrinsic properties for tetrahedral carbon/copper composites construction via electronic interface engineering

Abstract

The electronic structure induced interface properties are important for active control of the advanced equipment performance. Nevertheless, it is difficult to reveal the intrinsic mechanism by experiments. In this paper, the interfacial properties and electronic characteristics of eight different stacking ta-C/Cu interfaces were studied via first principles method. The work of adhesion of ta-C/Cu(110)-2nd interface the largest (6.19 J/m2) and its interfacial energy is the smallest (3.74 J/m2), which indicates that it is the most stable structure with the smallest interface formation resistance. In addition, the polar covalent bonds dominated by electronic structures are major contributor of the ta-C/Cu interface properties. During tensile process, the critical strain of ta-C/Cu(110)-2nd is the largest (17.0 %), and the tensile strength of ta-C/Cu(100)-2nd is the largest (61.59 GPa). When all interfaces are fractured under tensile force, the atoms on Cu surfaces are transferred to ta-C surfaces and separated into two free parts. When the energy of one of the wave valleys first reaches the threshold of the lowest plane-averaged potential, the interfacial structure breaks at the interfacial gap corresponding to the wave valley. Changes in interfacial bonding properties can therefore be judged by changes in the magnitude of the electrostatic potential.