9-13 July 2012
Van der Waals density functional studies of hydrogen adatoms on bilayer graphene
Presented by Mr. Edwin MAPASHA on 10 Jul 2012 from 11:00 to 11:20
Type: Oral Presentation
Track: Track A - Division for Condensed Matter Physics and Materials
We present a comparative density functional study of the adsorption of hydrogen atoms on bilayer graphene. Two different exchange-correlation functionals are employed to explore the possible configurations of hydrogen adsorption at 50% coverage. Using the non-local van der Waals density functional, we identify three distinct competing configurations that retain the coupled bilayer structure at 0 K. One of the configurations undergoes a spontaneous transformation from hexagonal to tetrahedral structure, under hydrogenation, with the energy of formation of -0.06 eV (GGA) and -0.37 eV (vdW-DFC09x).This configuration has a finite band gap of around 3 eV, whereas all other competing configurations are semi-metallic.
Prof Nithaya Chetty email@example.com University of pretoria