10.1021/nn403939r.s001
Jeongmin Hong
Jeongmin
Hong
Elena Bekyarova
Elena
Bekyarova
Walt A. de Heer
Walt
A. de Heer
Robert C. Haddon
Robert C.
Haddon
Sakhrat Khizroev
Sakhrat
Khizroev
Chemically Engineered Graphene-Based 2D Organic Molecular Magnet
American Chemical Society
2013
graphene surface
characterization techniques
carbon nanosystems
graphene nanoribbons
functionality directions
400 K
sample magnetometry
quantum tunneling
scanning probe microscopy
mesoscopic dimensions
Chemically
superconducting quantum interference
NP
SPM
magnetization
graphene systems
surface magnetoelectric properties
future
nitrophenyl functionalized graphene
CIN
functionalization
graphene orientations
MOKE
VSM
2013-11-26 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Chemically_Engineered_Graphene_Based_2D_Organic_Molecular_Magnet/2350123
Carbon-based magnetic materials and structures of mesoscopic dimensions may offer unique opportunities for future nanomagnetoelectronic/spintronic devices. To achieve their potential, carbon nanosystems must have controllable magnetic properties. We demonstrate that nitrophenyl functionalized graphene can act as a room-temperature 2D magnet. We report a comprehensive study of low-temperature magnetotransport, vibrating sample magnetometry (VSM), and superconducting quantum interference (SQUID) measurements before and after radical functionalization. Following nitrophenyl (NP) functionalization, epitaxially grown graphene systems can become organic molecular magnets with ferromagnetic and antiferromagnetic ordering that persists at temperatures above 400 K. The field-dependent, surface magnetoelectric properties were studied using scanning probe microscopy (SPM) techniques. The results indicate that the NP-functionalization orientation and degree of coverage directly affect the magnetic properties of the graphene surface. In addition, graphene-based organic magnetic nanostructures were found to demonstrate a pronounced magneto-optical Kerr effect (MOKE). The results were consistent across different characterization techniques and indicate room-temperature magnetic ordering along preferred graphene orientations in the NP-functionalized samples. Chemically isolated graphene nanoribbons (CINs) were observed along the preferred functionality directions. These results pave the way for future magnetoelectronic/spintronic applications based on promising concepts such as current-induced magnetization switching, magnetoelectricity, half-metallicity, and quantum tunneling of magnetization.