Query: electrical conductivity and dielectric properties of graphene oxide

Candidate papers:

abstract: Abstract The present work was aimed to investigate the electric and dielectric behavior of synthesized graphene oxide as a function of both temperature ranging from the ambient to 873K and frequency varying between 10 Hz and 10 MHz. Graphene oxide nanosheets were prepared by the modified Hummer's Method. The structural and morphological properties were characterized by X Ray diffraction, FTIR and Raman spectroscopies. The ac conductivity, dc conductivity, dielectric constant and loss factors were obtained. Constant phase elements allowed to obtain an equivalent electrical circuit by fitting the theoretical approximations to the experimental results. The synthesized graphene oxide (GO) exhibited high values of dielectric constant e'(o) and low losses. The obtained GO could be a good candidate for semiconductor compound and may be used in colossal memories.
author_names: K Riahi

Nasr Sdiri

Dorra Jellouli Ennigrou

Karima Horchani-Naifer
title: Investigations on electrical conductivity and dielectric properties of graphene oxide nanosheets synthetized from modified Hummer's method
year: 2020

abstract: The aim of this work is to invent a novel technology for manufacture not only graphene oxide, but also conductive graphene oxide. This is the novelty in this technology, which is not available in any other method for preparing graphene oxide. This study describes a unique way for preparation of conductive nano particles of graphene oxide, GO. The advantages of this technology is very simple, low cost, short time of preparation and can be manufacture a large amount of conductive GO by firing polyvinyl alcohol PVA on SiO2/pSi to preparation this assembly GO/SiO2/pSi as a Schottky barrier diode or Metal Oxide Semiconductor, MOS. Besides the pioneering in this article GO is deemed insulator, however with rising temperature through firing PVA, its conductivity remarkably enhances and the produced GO can be used as a conductor. The as prepared sample has been characterized using different techniques (e.g. Scanning Electron Microscopy (SEM) Raman Spectroscopy, X Ray diffraction (XRD) and Impedance Spectroscopy. Temperature, voltage and frequency dependences of M' M' 1/C2, Rs, sac and tand of GO/SiO2//p Si diodes were achieved in the varied ranges of voltage and frequency. I V characteristic of GO/SiO2/pSi Schottky diode is taken at different temperatures. The elementary factors of the diode such as barrier height (Phb) series resistance (Rs) and ideality factor (n) of GO/SiO2/pSi are also considered. The nyquist plot of M'(M' at different voltages and temperatures were examined.
author_names: A Ashery

Mohammed A Moussa

Gamal Turky
title: Enhancement of Electrical and Dielectric Properties of Graphene Oxide nanoparticle Based Devices
venue: Silicon
year: 2021

abstract: Synthesis of a new nanocomposite composed of poly (vinyl chloride co vinyl acetate co 2 hydroxypropyl acrylate) (PVVH) copolymer and graphene oxide (GO) was successfully achieved using solution casting technique. Dielectric properties of the nanocomposite were investigated in the frequency range (10 Hz to 10 MHz) over the temperature range (298 373 K) Many variables such as: dielectric constant, dielectric loss, loss tangent, electric moduli and AC conductivity were studied with changing frequency and temperature, showing improvement in the nanocomposite properties with both of them. The non Debye behaviour of the samples was confirmed from the electric modulus analysis. AC conductivity (sac) was found to follow Jonscher's universal power law. The enhancement in (sac) with frequency and temperature has implied the presence of free charge carriers that pass by hopping through defect sites over the potential barriers separating them in the PVVH/GO matrix. The correlated barrier hopping (CBH) model was found to be the best choice for describing AC conduction mechanism in the current nanocomposite over the above temperature range. Scaling of (sac) carried out for the prepared samples has exhibited that charge carriers within the current matrix follow a common conduction mechanism. A comparison between maximum barrier height and activation energy has been carried out to demonstrate the charge carriers transport mechanism. The PVVH based nanocomposite with the highest concentration of GO (4 wt% has achieved the highest enhancement in (sac) and mechanical properties, suggesting the feasibility of using it in designing electrochemical and energy storage devices.
author_names: A Y Yassin

A Raouf Mohamed

A M Abdelghany

Elmetwaly M Abdelrazek
title: Enhancement of dielectric properties and AC electrical conductivity of nanocomposite using poly (vinyl chloride co vinyl acetate co 2 hydroxypropyl acrylate) filled with graphene oxide
venue: Journal of Materials Science: Materials in Electronics
year: 2018

abstract: Abstract Graphene oxide (GO) has been synthesized by modified Hummers' method and characterized by Fourier transform infrared spectroscopy, ultraviolet visible spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, X ray diffraction technique and Raman spectroscopy. GO characterized using Fourier transform infrared spectra shows that the graphite powder is strongly oxidized by resilient oxidants and the oxygen atoms are present in form of functional groups such as COOH, O H, C O C, and C O, bonds. GO pellets were prepared to study its dielectric properties as a function of frequency. Dielectric permittivity and electrical conductivity of GO strongly depends upon the extent of temperature.
author_names: Pushpendra Kumar

Santhosh Penta

Shyama Prasad Mahapatra
title: Dielectric Properties of Graphene Oxide Synthesized by Modified Hummers' Method from Graphite Powder
venue: Integrated Ferroelectrics
year: 2019

abstract: Abstract Polyaniline nanofibers (PANI NFs) was prepared by Interfacial and rapid mixing polymerization Fourier transform infrared (FTIR) X ray diffraction (XRD) and Scanning Electron Microscope (SEM) were used to examine of pure nanofibers. The structural, optical, thermal, and conductivity properties of pure blend and PNCs were studied by using FTIR, XRD, SEM, UV Vis. DTA TGA, and Ac conductivity measurement techniques and have been prepared using the casting method. The analysis of FT IR reflects forming hydrogen bond between the PANI and PMMA. Also it's confirmed the presence interaction between GO NPs with the functional groups of PMMA/PANI matrix. The XRD data revealed the increase of amorphous domains of nanocomposites comparing to that of the pure polymer blend. The SEM indicates the uniform distribution of GO NPs on the surface of the prepared samples. From UV. Vis showed the values of optical energy gap (direct and indirect) for pure blend and nanocomposites decreases with increasing content of GO NPs. Based on DTA and TGA data, the thermal stability of all the investigated samples were improved and the activation energies were calculated. Electrical conductivity analysis indicates that the 0.9 wt sample have a larger conductivity compared to that of prepared samples. The increase in conductivity was mainly due to the increase in mobility of charge carrier according to free volume model.
author_names: M M Abutalib
title: Insights into the structural, optical, thermal, dielectric, and electrical properties of PMMA/PANI loaded with graphene oxide nanoparticles
year: 2019

abstract: Abstract Graphene oxide (GO) films can be used in structural dielectric capacitors (SDCs) as both primary structures and energy storage devices for large transportation equipment like aircraft. To meet the high requirements for aviation application, in this paper the mechanical and dielectric properties of GO films were optimized by concisely tailoring their carbon to oxygen (C/O) ratio. Our results show that both the mechanical and electrical conductivity of GO films increase with increasing the C/O ratio. This work also demonstrates that both mechanical and dielectric properties of GO films can be enhanced simultaneously through a mild reduction whilst retaining the electrical insulating nature of GO for SDC applications. The insights provided in this work would be beneficial not only for SDC applications but also for fundamental studies and developments of GO related materials.
author_names: Kit-ying Chan

Ardeshir Baktash

Baris Demir

Edwin L H Mayes

Dan Yang

Duy Quang Pham

Keng-Te Lin

Adrian Mouritz

Andrew Siao Ming Ang

Bronwyn L Fox

Bo Zhu

Han Lin

Baohua Jia

Kin-tak Alan Lau
title: Tailoring mechanical and electrical properties of graphene oxide film for structural dielectric capacitors
year: 2021

abstract: Graphene metal nanocomposites are the best candidates for the greater sensitivity for various applications. We have prepared Graphene Tin Oxide (G/SnO2) nanocomposite by using facile eco friendly Anton Paar microwave synthesis reactor method. X ray diffraction patterns revealed the formation of G/SnO2 nanocomposite. The scanning electron microscopy and transmission electron microscopy images show a uniform distribution of nano needles on the graphene surface and the average particle size was found to be in the range of 3 5 nm. The G/SnO2 composite shows an enhanced optical property, i.e. tunability in the band of pristine SnO2 nanoparticles while in contacted with graphene. The dielectric properties of the G/SnO2 nanocomposite were measured in the frequency ranges of 75Hz to 4MHz and real value of dielectric constant is found to be 1200, which is quite larger than that of pristine SnO2 nanoparticle, i.e. 12. Further, AC conductivity analysis revealed that the G/SnO2 is two orders conductive than the pristine SnO2. This work may offer an effective and economically viable for the preparation of graphene/metal oxide nanocomposites for various applications.
author_names: Moheeta Khan

Azra Parveen
title: Microwave Assisted Synthesis of Graphene/SnO2 Nanocomposite and its Structural, Dielectric and Electrical Properties
year: 2020

abstract: Graphene oxide (GO) nanofiller were incorporated in PVP/PVA blend films for the preparation of nanocomposite polymer films by the solution cast method. The films were characterized using SEM, D.C and A.C and dielectric properties studies at room temperature. SEM structure shows that the GO exfoliated and uniformly dispersed in PVP/PVA matrix. DC conductivity studies were under taken at (303 336) K, and the conductivity was found to be 3.3x10 O.cm for the polymer film prepared at 336K. The A.C electrical conductivity increase with the increase of frequency. The dielectric properties were measured the frequency range 100Hz 5MHz at room temperature show that the dielectric constant (real and imaginary) decrease with the increase of Graphene oxide nanoparticles concentrations.
author_names: Nadia Abbas Ali
title: Graphene oxide on the electrical properties D.C and A.C and dielectric constant of PVP/PVA Nanocomposites
year: 2018

abstract: Lanthanum Ferrite based nanocomposites were prepared with various Graphene oxide contents by the hydrothermal method. The crystalline structure, morphological properties, electrical and optical properties of samples were investigated. X ray diffraction results indicate that all the nano electroceramics are polycrystalline with an Orthorhombic structure. Results from scanning and transmission electron microscopes indicate that the Bismuth ferrite/Graphene oxide powders have nanostructure. The optical band gaps of the nano electroceramics were calculated for the various amount of Graphene oxide. The electrical properties of samples were investigated with the temperature depend on conductivity measurements. The measurement shows that the electrical conductivity changes with increasing temperature and graphene oxide dopants of all samples. Activation energy (EA) values of the nanocomposites decrease with increasing graphene oxide content. The dielectric properties of Lanthanum Ferrite/Graphene Oxide nanocomposites (real and imaginer) with respect to frequency variation (1 KHz 5 MHz) were measured at room temperature. The relative permittivity (e' dielectric loss (e' and alternating current conductivity (sac) values of the samples were estimated. It is show that (e' (e' and (sac) increase with increasing frequency. The polarization electric field hysteresis loop of all Lanthanum Ferrite/Graphene Oxide nano electroceramics was measured at the room temperature. The loop shows proper saturation with enhanced saturation polarization (Ps) remnant polarization (Pr) and coercive electric field (Ec) The obtained findings suggest that the physical and electrical properties of Lanthanum Ferrite/Graphene Oxide nano electroceramics can be changed by Graphene Oxide doping. These materials can be used for a variety of technological applications in the field of dielectric and ferroelectric.
author_names: C Aydin

H Aydin

Mustafa Taskin

Fahrettin Yakuphanoglu
title: A Novel Study: The Effect of Graphene Oxide on the Morphology, Crystal Structure, Optical and Electrical Properties of Lanthanum Ferrite Based Nano Electroceramics Synthesized by Hydrothermal Method.
venue: Journal of nanoscience and nanotechnology
year: 2019

abstract: In this study, Yttrium Ferrite based nano electroceramics were prepared by the doping at various ratios of graphene oxide by the hydrothermal method. The obtained doped and undoped samples were characterized by XRD, SEM, FTIR, DTA, UV VIS NIR spectroscopy, temperature dependent electrical resistance changes and dielectric measurements. From the XRD results, it is observed that the obtained samples are polycrystalline with an Orthorhombic structure. The crystal parameters are changed with the doping of graphene oxide. FTIR spectra indicate that the graphene oxide changes the peak intensities. This confirms the incorporation of the graphene oxide into the ceramic structure. The doping of the graphene oxide changes the optical band gaps of the samples. The dielectric constants of the samples are changed with the graphene oxide. The DC electrical conductivity measurements confirm the semiconducting behavior of the samples. The obtained results indicate that the electronic and nanostructure of the synthesized electroceramics can be controlled by the doping of graphene oxide for electronic and energy applications.
author_names: H Aydin
title: THE EFFECT OF GRAPHENE OXIDE ON THE STRUCTURAL AND ELECTRICAL PROPERTIES OF YTTRIUM FERRITE BASED NANOPOWDERS
venue: European Journal of Technic
year: 2019