Article ID Journal Published Year Pages File Type
1593064 Solid State Communications 2012 6 Pages PDF
Abstract

In this paper, we have studied functionalization of 5–7 edge-reconstructed graphene nanoribbons by ab initio density functional calculations. Our studies show that hydrogenation at the reconstructed edges is favorable in contrast to the case of unreconstructed 6–6 zigzag edges, in agreement with previous theoretical results. Thermodynamical calculations reveal the relative stability of single and dihydrogenated edges under different temperatures and chemical potential of hydrogen gas. From phonon calculations, we find that the lowest optical phonon modes are hardened due to 5–7 edge reconstruction compared to the 6–6 unreconstructed hydrogenated edges. Finally, edge functionalization by Fe atoms reveals a dimerized Fe chain structure along the edges. The magnetic exchange coupling across the edges varies between ferromagnetic and antiferromagnetic ones with the variation of the width of the nanoribbons.

► Dihydrogenation is highly probable at the edge of a reconstructed nanoribbon. ► The lowest optical phonon mode is hardened due to edge reconstruction. ► Fe atoms form a dimerized chain at the edge of reconstructed nanoribbons. ► Magnetic exchange across the Fe-decorated edges varies between ferromagnetic and antiferromagnetic coupling.

Related Topics
Physical Sciences and Engineering Materials Science Materials Science (General)
Authors
, , , , , ,