Enhanced Cu/graphene adhesion by doping with Cr and Ti: A first principles prediction
(1. Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education, School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, University of Pennsylvania, Philadelphia 19104, USA;
3. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China)
2. School of Materials Science and Engineering, University of Pennsylvania, Philadelphia 19104, USA;
3. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China)
Abstract: We presented a density functional theory study on doping effects of transition metals (Cr and Ti) on the Cu/graphene interface adhesion. Various undoped Cu/graphene interface structures were constructed using both the sandwich and the surface models. Energetics calculations showed that the interface binding strength only weakly depends on interface coordination. Both interface models predicted the top-fcc coordination type as the most energy-favored, with a low binding energy value. Segregated Cr prefers to substituting for Cu, while Ti occupies a hollow site at the interface. Although the segregation tendencies are both very weak, once present on the interface, both dopants can greatly increase the interface binding energy and improve the adhesion.
Key words: Cu; Cr; Ti; grapheme; doping; interface; first principles