Graphene supported graphone/graphane bilayer nanostructure material for spintronics.
We report an investigation into the magnetic and electronic properties of partially hydrogenated vertically aligned few layers graphene (FLG) synthesized by microwave plasma enhanced chemical vapor deposition. The FLG samples are hydrogenated at different substrate temperatures to alter the degree of hydrogenation and their depth profile. The unique morphology of the structure gives rise to a unique geometry in which graphane/graphone is supported by graphene layers in the bulk, which is very different from other widely studied structures such as one-dimensional nanoribbons. Synchrotron based x-ray absorption fine structure spectroscopy measurements have been used to investigate the electronic structure and the underlying hydrogenation mechanism responsible for the magnetic properties. While ferromagnetic interactions seem to be predominant, the presence of antiferromagnetic interaction was also observed. Free spins available via the conversion of sp(2) to sp(3) hybridized structures, and the possibility of unpaired electrons from defects induced upon hydrogenation are thought to be likely mechanisms for the observed ferromagnetic orders.
Department of Physics, College of Science, Engineering and Technology, University of South Africa, Private Bag X6, Florida, 1710, Science Campus, Christiaan de Wet and Pioneer Avenue, Florida Park, Johannesburg, South Africa.
Sekhar C
SC
Ray
1] Nanotechnology and Integrated Bioengineering Center (NIBEC), School of Engineering, University of Ulster, Jordanstown campus, Newtownabbey, BT37 0QB, United Kingdom [2].
Navneet
N
Soin
Department of Physics, University of the Witwatersrand, Johannesburg, South Africa.
Thuto
T
Makgato
Department of Physics, Tamkang University, Tamsui 251, Taipei, Taiwan.
C H
CH
Chuang
Department of Physics, Tamkang University, Tamsui 251, Taipei, Taiwan.
W F
WF
Pong
Department of Physics, School of Natural Sciences, Shiv Nadar University, Gautam Budh Nagar 203207, UP, India.
Susanta S
SS
Roy
Department of Physics, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa.
Sarit K
SK
Ghosh
1] Department of Physics, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa [2] Max Planck Institute for Chemical Physics of Solids, Nöthnitzerstr, 40, 01187 Dresden, Germany.
André M
AM
Strydom
Nanotechnology and Integrated Bioengineering Center (NIBEC), School of Engineering, University of Ulster, Jordanstown campus, Newtownabbey, BT37 0QB, United Kingdom.
J A
JA
McLaughlin