Possible ferro-electro-magnetic behaviours of graphene-based materials: hydrogenated graphene, MWCNTs and reduced graphene-oxide (GO)

TL;DR

This study explores how different graphene-based materials show unique electric and magnetic properties that could be useful for storage and information processing.

Contribution

The paper reveals distinct ferro-electro-magnetic behaviors in hydrogenated graphene, MWCNTs, and r-GO due to their lattice defects and electronic structures.

Findings

MWCNTs show higher magnetization than H-graphene and r-GO.

H-graphene has the highest electric polarization among the materials studied.

Valence band maximum differences are linked to defects affecting magnetic and polarization behaviors.

Abstract

This study investigated the electric polarization and magnetic behaviours of various graphene-based materials, including hydrogenated graphene (H-graphene), multi-wall carbon nanotubes (MWCNTs), and reduced graphene oxide (r-GO). Results showed that MWCNTs exhibit higher magnetization, with a magnetic squareness (Mr/Ms) of approximately ≈0.5, compared to H-graphene (≈0.25). H-graphene exhibits the highest electric polarization compared to MWCNTs/r-GO, whereas r-GO demonstrates the lowest levels of polarization and magnetization compared to H-graphene/MWCNTs. The valence band maximum (4.08 eV for MWCNTs, 4.26 eV for H-graphene, and 4.78 eV for r-GO) in quasi-localized states at the Fermi level results in defects in the graphene-based lattice, which are associated with dipole moment and lead to alterations in magnetic behaviours. Different density of states (DOS) is attributed from the ultra-violet photoelectron spectra and the small variations in the Fermi edge is observed in H-graphene, MWCNTs, and r-GO are responsible for the observed magnetisation and polarizations. The unique polarization/magnetization behaviours present an opportunity for potential exploitation in storage and information processing technologies in the science and engineering community.

This study investigated the electric polarization and magnetic behaviours of various graphene-based materials, including hydrogenated graphene (H-graphene), multi-wall carbon nanotubes (MWCNTs), and reduced graphene oxide (r-GO).

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