Electronic, electrical and magnetic behaviours of reduced graphene-oxide functionalized with silica coated gold nanoparticles

David O. Idisi; Haydar Ali; J. A. Oke; Sweety Sarma; S. J. Moloi; Sekhar C. Ray; H. T. Wang; Nikhil R. Jana; W. F. Pong; André M. Strydom

doi:10.1016/j.apsusc.2019.03.271

Electronic, electrical and magnetic behaviours of reduced graphene-oxide functionalized with silica coated gold nanoparticles

David O. Idisi, Haydar Ali, J. A. Oke, Sweety Sarma, S. J. Moloi, Sekhar C. Ray, H. T. Wang, Nikhil R. Jana, W. F. Pong, André M. Strydom

Physics

Research output: Contribution to journal › Article › peer-review

28 Citations (Scopus)

Abstract

We have synthesized graphene-oxide (GO) by the modified hummer's process and subsequently reduced it with gold-nanoparticles (Au-NPs) using silica coated colloidal Au-NPs and hydrazine monohydrate solutions to form r-GO:Au-NPs nanocomposites. We have studied the microstructure, electronic, electrical and magnetic properties of r-GO and r-GO:Au-NPs nanocomposites. We have observed from the Raman spectroscopy that the intensity of D-peak (disorder) gets reduced with respect to G (graphite-cluster) in r-GO:Au-NPs composites. The reduction of I _D /I _G ratio obtained from Raman spectra [r-GO: 1.22 → r-GO:(Au-NPs) _4.88 : 0.98] clearly indicates that the sp ² -cluster is reduced in r-GO:Au-NPs nanocomposites. The reduction of sp ² -cluster and/or enhancement of sp ³ -cluster is due to replacement of sp ² -cluster by the Au-NPs. This observation also observed from the X-ray absorption near edge structure (XANES) spectroscopy, X-ray photoelectron spectroscopy (XPS) measurements that are consistence with reduction of conductivity as we observe from the current (I) - voltage (V) characteristics of the nanocomposites. Magnetic M-H hysteresis loops show the magnetization is enhanced in r-GO:Au-NPs nanocomposites. We believe that the reduction of conductivity and enhancement of magnetization of r-GO:Au nanocomposites would be most suitable for ferro-electro-magnetic materials for the memory storage device applications.

Original language	English
Pages (from-to)	106-113
Number of pages	8
Journal	Applied Surface Science
Volume	483
DOIs	https://doi.org/10.1016/j.apsusc.2019.03.271
Publication status	Published - 31 Jul 2019

Keywords

I-V
M-H
R-GO
R-GO:Au-NPs
XANES
XPS

ASJC Scopus subject areas

General Chemistry
Condensed Matter Physics
General Physics and Astronomy
Surfaces and Interfaces
Surfaces, Coatings and Films

Access to Document

10.1016/j.apsusc.2019.03.271

Cite this

@article{ad52edd829954dcf814208d65614728e,

title = "Electronic, electrical and magnetic behaviours of reduced graphene-oxide functionalized with silica coated gold nanoparticles",

abstract = " We have synthesized graphene-oxide (GO) by the modified hummer's process and subsequently reduced it with gold-nanoparticles (Au-NPs) using silica coated colloidal Au-NPs and hydrazine monohydrate solutions to form r-GO:Au-NPs nanocomposites. We have studied the microstructure, electronic, electrical and magnetic properties of r-GO and r-GO:Au-NPs nanocomposites. We have observed from the Raman spectroscopy that the intensity of D-peak (disorder) gets reduced with respect to G (graphite-cluster) in r-GO:Au-NPs composites. The reduction of I D /I G ratio obtained from Raman spectra [r-GO: 1.22 → r-GO:(Au-NPs) 4.88 : 0.98] clearly indicates that the sp 2 -cluster is reduced in r-GO:Au-NPs nanocomposites. The reduction of sp 2 -cluster and/or enhancement of sp 3 -cluster is due to replacement of sp 2 -cluster by the Au-NPs. This observation also observed from the X-ray absorption near edge structure (XANES) spectroscopy, X-ray photoelectron spectroscopy (XPS) measurements that are consistence with reduction of conductivity as we observe from the current (I) - voltage (V) characteristics of the nanocomposites. Magnetic M-H hysteresis loops show the magnetization is enhanced in r-GO:Au-NPs nanocomposites. We believe that the reduction of conductivity and enhancement of magnetization of r-GO:Au nanocomposites would be most suitable for ferro-electro-magnetic materials for the memory storage device applications.",

keywords = "I-V, M-H, R-GO, R-GO:Au-NPs, XANES, XPS",

author = "Idisi, {David O.} and Haydar Ali and Oke, {J. A.} and Sweety Sarma and Moloi, {S. J.} and Ray, {Sekhar C.} and Wang, {H. T.} and Jana, {Nikhil R.} and Pong, {W. F.} and Strydom, {Andr{\'e} M.}",

note = "Publisher Copyright: {\textcopyright} 2019",

year = "2019",

month = jul,

day = "31",

doi = "10.1016/j.apsusc.2019.03.271",

language = "English",

volume = "483",

pages = "106--113",

journal = "Applied Surface Science",

issn = "0169-4332",

publisher = "Elsevier",

}

TY - JOUR

T1 - Electronic, electrical and magnetic behaviours of reduced graphene-oxide functionalized with silica coated gold nanoparticles

AU - Idisi, David O.

AU - Ali, Haydar

AU - Oke, J. A.

AU - Sarma, Sweety

AU - Moloi, S. J.

AU - Ray, Sekhar C.

AU - Wang, H. T.

AU - Jana, Nikhil R.

AU - Pong, W. F.

AU - Strydom, André M.

PY - 2019/7/31

Y1 - 2019/7/31

N2 - We have synthesized graphene-oxide (GO) by the modified hummer's process and subsequently reduced it with gold-nanoparticles (Au-NPs) using silica coated colloidal Au-NPs and hydrazine monohydrate solutions to form r-GO:Au-NPs nanocomposites. We have studied the microstructure, electronic, electrical and magnetic properties of r-GO and r-GO:Au-NPs nanocomposites. We have observed from the Raman spectroscopy that the intensity of D-peak (disorder) gets reduced with respect to G (graphite-cluster) in r-GO:Au-NPs composites. The reduction of I D /I G ratio obtained from Raman spectra [r-GO: 1.22 → r-GO:(Au-NPs) 4.88 : 0.98] clearly indicates that the sp 2 -cluster is reduced in r-GO:Au-NPs nanocomposites. The reduction of sp 2 -cluster and/or enhancement of sp 3 -cluster is due to replacement of sp 2 -cluster by the Au-NPs. This observation also observed from the X-ray absorption near edge structure (XANES) spectroscopy, X-ray photoelectron spectroscopy (XPS) measurements that are consistence with reduction of conductivity as we observe from the current (I) - voltage (V) characteristics of the nanocomposites. Magnetic M-H hysteresis loops show the magnetization is enhanced in r-GO:Au-NPs nanocomposites. We believe that the reduction of conductivity and enhancement of magnetization of r-GO:Au nanocomposites would be most suitable for ferro-electro-magnetic materials for the memory storage device applications.

AB - We have synthesized graphene-oxide (GO) by the modified hummer's process and subsequently reduced it with gold-nanoparticles (Au-NPs) using silica coated colloidal Au-NPs and hydrazine monohydrate solutions to form r-GO:Au-NPs nanocomposites. We have studied the microstructure, electronic, electrical and magnetic properties of r-GO and r-GO:Au-NPs nanocomposites. We have observed from the Raman spectroscopy that the intensity of D-peak (disorder) gets reduced with respect to G (graphite-cluster) in r-GO:Au-NPs composites. The reduction of I D /I G ratio obtained from Raman spectra [r-GO: 1.22 → r-GO:(Au-NPs) 4.88 : 0.98] clearly indicates that the sp 2 -cluster is reduced in r-GO:Au-NPs nanocomposites. The reduction of sp 2 -cluster and/or enhancement of sp 3 -cluster is due to replacement of sp 2 -cluster by the Au-NPs. This observation also observed from the X-ray absorption near edge structure (XANES) spectroscopy, X-ray photoelectron spectroscopy (XPS) measurements that are consistence with reduction of conductivity as we observe from the current (I) - voltage (V) characteristics of the nanocomposites. Magnetic M-H hysteresis loops show the magnetization is enhanced in r-GO:Au-NPs nanocomposites. We believe that the reduction of conductivity and enhancement of magnetization of r-GO:Au nanocomposites would be most suitable for ferro-electro-magnetic materials for the memory storage device applications.

KW - I-V

KW - M-H

KW - R-GO

KW - R-GO:Au-NPs

KW - XANES

KW - XPS

UR - http://www.scopus.com/inward/record.url?scp=85063450311&partnerID=8YFLogxK

U2 - 10.1016/j.apsusc.2019.03.271

DO - 10.1016/j.apsusc.2019.03.271

M3 - Article

AN - SCOPUS:85063450311

SN - 0169-4332

VL - 483

SP - 106

EP - 113

JO - Applied Surface Science

JF - Applied Surface Science

ER -

Electronic, electrical and magnetic behaviours of reduced graphene-oxide functionalized with silica coated gold nanoparticles

Abstract

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this