Studies of physicochemical properties of graphite oxide and thermally exfoliated/reduced graphene oxide

Abstract The aim of the experimental research studies was to determine some electrical properties of graphite oxide and thermally exfoliated/reduced graphene oxide. The authors tried to interpret the obtained physicochemical results. For that purpose, both resistance measurements and investigation studies were carried out in order to characterize the samples. The resistance was measured at various temperatures in the course of composition changes of gas atmospheres (which surround the samples). The studies were also supported by such methods as: scanning electron microscopy (SEM), Raman spectroscopy (RS), atomic force microscopy (AFM) and thermogravimetry (TG). Moreover, during the experiments also the elemental analyses (EA) of the tested samples (graphite oxide and thermally exfoliated/reduced graphene oxide) were performed.

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Reduced Graphene Oxide–Epoxy Grafted Poly(Styrene-Co-Acrylate) Composites for Corrosion Protection of Mild Steel

Coatings ◽

10.3390/coatings9100666 ◽

2019 ◽

Vol 9 (10) ◽

pp. 666

Author(s):

Xinchuan Fan ◽

Yue Hu ◽

Yijun Zhang ◽

Jiachen Lu ◽

Xiaofeng Chen ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

X Ray Diffraction ◽

Corrosion Properties ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Scanning Electron

Reduced graphene oxide–epoxy grafted poly(styrene-co-acrylate) composites (GESA) were prepared by anchoring different amount of epoxy modified poly(styrene-co-acrylate) (EPSA) onto reduced graphene oxide (rGO) sheets through π–π electrostatic attraction. The GESA composites were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The anti-corrosion properties of rGO/EPSA composites were evaluated by electro-chemical impedance spectroscopy (EIS) in hydroxyl-polyacrylate coating, and the results revealed that the corrosion rate was decreased from 3.509 × 10−1 to 1.394 × 10−6 mm/a.

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Facile and green synthesis of silver nanoparticle-reduced graphene oxide composite and its application as nonenzymatic electrochemical sensor for hydrogen peroxide

Current Chemistry Letters ◽

10.5267/j.ccl.2021.3.002 ◽

2021 ◽

pp. 295-308 ◽

Cited By ~ 1

Author(s):

Jagdish C. Bhangoji ◽

Srikant Sahoo ◽

Ashis Kumar Satpati ◽

Suresh S. Shendage

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Dynamic Range ◽

Electrochemical Impedance ◽

Metal Foil ◽

Reduced Graphene ◽

Scanning Electron

A simple and environment friendly protocol has been developed for the synthesis of Ag nanoparticles (AgNPs) supported on reduced graphene oxide (rGO) with copper metal foil as reductant. The prepared AgNPs-rGO, nanocomposite was characterized by various analytical techniques such as scanning electron microscopy (SEM), field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD). The electrochemical performance of the material has been evaluated using cyclic voltammetry (CV), chronoamperometry and electrochemical impedance spectroscopy (EIS). The average crystallite size of AgNPs is found to be 32.34 nm. The application of prepared electrocatalyst (AgNPs-rGO) as a non-enzymatic sensor is examined through the modified electrode with the synthesized AgNPs-rGO. The sensor showed excellent performance toward H2O2 reduction with a sensitivity of 12.73 µA.cm-2.mM-1, with a linear dynamic range of 1.5 µM – 100 mM, and the detection limit of 1.90 µM (S/N = 3). Furthermore, the sensor displayed high sensitivity, reproducibility, stability and selectivity for the determination of H2O2. The results demonstrated that AgNPs-rGO has potential applications as sensing material for quantitative determination of H2O2.

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Microstructure and microwave absorbing properties of reduced graphene oxide/Ni/multi-walled carbon nanotubes/Fe3O4 filled monolayer cement–based absorber

Advances in Mechanical Engineering ◽

10.1177/1687814018822886 ◽

2019 ◽

Vol 11 (1) ◽

pp. 168781401882288 ◽

Cited By ~ 3

Author(s):

Yafei Sun ◽

Min Chen ◽

Peiwei Gao ◽

Tianshu Zhou ◽

Hongwei Liu ◽

...

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Scanning Electron Microscopy ◽

Graphene Oxide ◽

Pore Structure ◽

Reduced Graphene Oxide ◽

Reduced Graphene ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Scanning Electron

In this article, reduced graphene oxide/Ni/multi-walled carbon nanotubes/Fe3O4 filled paste is synthesized with the aim of developing a novel shielding material. To do so, nano-dispersion presenting homogeneous distribution is made by ultrasonic dispersing technology. Next, the effects of nano-absorbent content on the fluidity, mechanical strength, pore structure, resistivity, and absorbing reflectivity of paste are studied. At the end, the microstructure of composite is uncovered by scanning electron microscopy, Fourier transformer infrared, X-ray diffraction images as well as the pore size distribution and absorbing reflectivity are revealed. The results indicate that a small load of reduced graphene oxide and other nano-absorbents can significantly reduce the fluidity and resistivity of paste, but its pore structure is improved so that its mechanical properties are increased. Scanning electron microscopy images indicate that reduced graphene oxide promotes the increasing and thickening of the cement hydration products as well as the growth of a large number of flower-like and compact bulk crystals. Furthermore, the minimum reflectivity of −10.6 dB is obtained in the range of 2–18 GHz while the effective bandwidth of 16 GHz is obtained when reflectivity is less than −5 dB. This research provides a new pathway for the preparation of monolayer cement–based absorber.

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Mechanical Characterization of Reduced Graphene Oxide Using AFM

Advances in Condensed Matter Physics ◽

10.1155/2019/8713965 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13 ◽

Cited By ~ 5

Author(s):

Alem Teklu ◽

Canyon Barry ◽

Matthew Palumbo ◽

Collin Weiwadel ◽

Narayanan Kuthirummal ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Graphene Oxide ◽

Young’S Modulus ◽

Reduced Graphene Oxide ◽

Young's Modulus ◽

Force Microscopy ◽

Atomic Force ◽

Reduction Cycle ◽

Reduced Graphene ◽

Oxide Sample

Nanoindentation coupled with Atomic Force Microscopy was used to study stiffness, hardness, and the reduced Young’s modulus of reduced graphene oxide. Oxygen reduction on the graphene oxide sample was performed via LightScribe DVD burner reduction, a cost-effective approach with potential for large scale graphene production. The reduction of oxygen in the graphene oxide sample was estimated to about 10 percent using FTIR spectroscopic analysis. Images of the various samples were captured after each reduction cycle using Atomic Force Microscopy. Elastic and spectroscopic analyses were performed on the samples after each oxygen reduction cycle in the LightScribe, thus allowing for a comparison of stiffness, hardness, and the reduced Young’s modulus based on the number of reduction cycles. The highest values obtained were after the fifth and final reduction cycle, yielding a stiffness of 22.4 N/m, a hardness of 0.55 GPa, and a reduced Young’s modulus of 1.62 GPa as compared to a stiffness of 22.8 N/m, a hardness of 0.58 GPa, and a reduced Young’s modulus of 1.84 GPa for a commercially purchased graphene film made by CVD. This data was then compared to the expected values of pristine single layer graphene. Furthermore, two RC circuits were built, one using a parallel plate capacitors made of light scribed graphene on a kapton substrate (LSGC) and a second one using a CVD deposited graphene on aluminum (CVDGC). Their RC time constants and surface charge densities were compared.

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Investigation into morphological and electromechanical surface properties of reduced-graphene-oxide-loaded composite fibers for bone tissue engineering applications: A comprehensive nanoscale study using atomic force microscopy approach

Micron ◽

10.1016/j.micron.2021.103072 ◽

2021 ◽

Vol 146 ◽

pp. 103072

Author(s):

Adrian Chlanda ◽

Ewa Walejewska ◽

Krystian Kowiorski ◽

Marcin Heljak ◽

Wojciech Swieszkowski ◽

...

Keyword(s):

Tissue Engineering ◽

Atomic Force Microscopy ◽

Graphene Oxide ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Reduced Graphene Oxide ◽

Surface Properties ◽

Force Microscopy ◽

Atomic Force ◽

Reduced Graphene

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Tetrachloroperylene diimide functionalized reduced graphene oxide sheets and their I–V behavior by current sensing atomic force microscopy

Journal of Materials Chemistry ◽

10.1039/c2jm34379g ◽

2012 ◽

Vol 22 (36) ◽

pp. 18839 ◽

Cited By ~ 10

Author(s):

Zhongjie Ren ◽

Dianming Sun ◽

Jianming Zhang ◽

Shouke Yan

Keyword(s):

Atomic Force Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Current Sensing ◽

Force Microscopy ◽

Atomic Force ◽

Reduced Graphene ◽

Graphene Oxide Sheets

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Improvement of polyacrylonitrile ultrafiltration membranes' properties using decane-functionalized reduced graphene oxide nanoparticles

Water Science & Technology Water Supply ◽

10.2166/ws.2016.059 ◽

2016 ◽

Vol 16 (5) ◽

pp. 1378-1387 ◽

Cited By ~ 3

Author(s):

Reyhaneh Kaveh ◽

Zahra Shariatinia ◽

Ahmad Arefazar

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Water Flux ◽

Superior Performance ◽

Oxide Nanoparticles ◽

Ultrafiltration Membranes ◽

Reduced Graphene ◽

Maximum Water ◽

Scanning Electron

The effect of decane-functionalized reduced graphene oxide (decane-rGO) was studied on the performance of polyacrylonitrile (PAN) ultrafiltration membranes. The results showed that the decane-rGO/PAN membranes had greater salt rejections relative to their corresponding GO/PAN membranes, confirming superior performance of modified decane-rGO particles. Also, the membrane with 0.2 wt% decane-rGO exhibited maximum water flux and appropriate salt rejection. The field-emission scanning electron microscopy (FE-SEM) micrographs illustrated that the sponge-like pores in the pristine PAN membrane were changed to a finger-like structure in the membrane containing up to 0.2 wt% of decane-rGO and the vertical holes were converted to horizontal holes by further increasing the decane-rGO concentration in the polymer matrix.

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