Photocatalytic reduction of graphene oxide with cuprous oxide film under UV-vis irradiation

AbstractWe have grown Cu2O films by different routes including self-oxidation and metal-organic deposition (MOD). The reduction efficiency of Cu2O films on graphene oxide (GO) synthesized by modified Hummer’s method has been studied. Surface morphology and chemical state of as-prepared Cu2O film and GO sheets reduced at different conditions have also been investigated using atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS). Results show that self-oxidation Cu2O film is more effective on phtocatalytic reduction of GO than MOD-Cu2O film. Moreover, reduction effect of self-oxidation Cu2O film to GO is comparable to that of environmental-friendly reducing agent of vitamin C. The present results offer a potentially eco-friendly and low-cost approach for the manufacture of reduced graphene oxide (RGO) by photocatalytic reduction.

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Metal-organic framework derived metal oxide/reduced graphene oxide nanocomposite, a new tool for the determination of dipyridamole

New Journal of Chemistry ◽

10.1039/d0nj05329e ◽

2021 ◽

Author(s):

Naeime Salandari-Jolge ◽

Ali A. Ensafi ◽

Behzad Rezaei

Keyword(s):

Myocardial Infarction ◽

Graphene Oxide ◽

High Performance ◽

High Selectivity ◽

Low Cost ◽

Metal Organic Framework ◽

Heart Patients ◽

Reduced Graphene ◽

Metal Organic

Dipyridamole is a prescribed medication used to treat cardiovascular diseases, angina pectoris, imaging tests for heart patients, and myocardial infarction. Therefore, high selectivity and sensitivity, low cost, and high-performance speed...

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A Facile and Green Synthesis of a MoO2-Reduced Graphene Oxide Aerogel for Energy Storage Devices

Materials ◽

10.3390/ma13030594 ◽

2020 ◽

Vol 13 (3) ◽

pp. 594 ◽

Cited By ~ 3

Author(s):

Mara Serrapede ◽

Marco Fontana ◽

Arnaud Gigot ◽

Marco Armandi ◽

Glenda Biasotto ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Chemical Reduction ◽

Low Cost ◽

Xps Analysis ◽

3D Scaffold ◽

Energy Storage Devices ◽

Reduced Graphene

A simple, low cost, and “green” method of hydrothermal synthesis, based on the addition of l-ascorbic acid (l-AA) as a reducing agent, is presented in order to obtain reduced graphene oxide (rGO) and hybrid rGO-MoO2 aerogels for the fabrication of supercapacitors. The resulting high degree of chemical reduction of graphene oxide (GO), confirmed by X-Ray Photoelectron Spectroscopy (XPS) analysis, is shown to produce a better electrical double layer (EDL) capacitance, as shown by cyclic voltammetric (CV) measurements. Moreover, a good reduction yield of the carbonaceous 3D-scaffold seems to be achievable even when the precursor of molybdenum oxide is added to the pristine slurry in order to get the hybrid rGO-MoO2 compound. The pseudocapacitance contribution from the resulting embedded MoO2 microstructures, was then studied by means of CV and electrochemical impedance spectroscopy (EIS). The oxidation state of the molybdenum in the MoO2 particles embedded in the rGO aerogel was deeply studied by means of XPS analysis and valuable information on the electrochemical behavior, according to the involved redox reactions, was obtained. Finally, the increased stability of the aerogels prepared with l-AA, after charge-discharge cycling, was demonstrated and confirmed by means of Field Emission Scanning Electron Microscopy (FESEM) characterization.

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Characterization of X-ray irradiated graphene oxide coatings using X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy

Powder Diffraction ◽

10.1017/s0885715613000109 ◽

2013 ◽

Vol 28 (2) ◽

pp. 68-71 ◽

Cited By ~ 40

Author(s):

Thomas N. Blanton ◽

Debasis Majumdar

Keyword(s):

Atomic Force Microscopy ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

High Energy ◽

X Ray Diffraction ◽

Carbon Phase ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Before And After

In an effort to study an alternative approach to make graphene from graphene oxide (GO), exposure of GO to high-energy X-ray radiation has been performed. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) have been used to characterize GO before and after irradiation. Results indicate that GO exposed to high-energy radiation is converted to an amorphous carbon phase that is conductive.

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Electrodeposition of NiSn-rGO Composite Coatings from Deep Eutectic Solvents and Their Physicochemical Characterization

Metals ◽

10.3390/met10111455 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1455

Author(s):

Sabrina Patricia Rosoiu ◽

Aida Ghiulnare Pantazi ◽

Aurora Petica ◽

Anca Cojocaru ◽

Stefania Costovici ◽

...

Keyword(s):

Graphene Oxide ◽

Electrochemical Impedance ◽

Composite Coatings ◽

Choline Chloride ◽

Physicochemical Characterization ◽

Metallic Matrix ◽

Deep Eutectic Solvents ◽

Force Microscopy ◽

Atomic Force ◽

Reduced Graphene

The present work describes, for the first time, the electrodeposition of NiSn alloy/reduced graphene oxide composite coatings (NiSn-rGO) obtained under pulse current electrodeposition conditions from deep eutectic solvents (choline chloride: ethylene glycol eutectic mixtures) containing well-dispersed GO nanosheets. The successful incorporation of the carbon-based material into the metallic matrix has been confirmed by Raman spectroscopy and cross-section scanning electron microscopy (SEM). A decrease in the crystallite size of the coating was evidenced when graphene oxide was added to the electrolyte. Additionally, the topography and the electrical properties of the materials were investigated by atomic force microscopy (AFM). The corrosion behavior in 0.5 M NaCl solution was analyzed through potentiodynamic polarization and electrochemical impedance spectroscopy methods for different immersion periods, up to 336 h, showing a slightly better corrosion performance as compared to pure NiSn alloy.

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Nonenzymatic Electrochemical Immunosensor Using Ferroferric Oxide–Manganese Dioxide–Reduced Graphene Oxide Nanocomposite as Label for α-Fetoprotein Detection

NANO ◽

10.1142/s1793292016501162 ◽

2016 ◽

Vol 11 (10) ◽

pp. 1650116 ◽

Cited By ~ 5

Author(s):

Wensi Jian ◽

Chunping Wang ◽

Zuanguang Chen ◽

Yanyan Yu ◽

Duanping Sun ◽

...

Keyword(s):

Graphene Oxide ◽

Manganese Dioxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Low Cost ◽

Synergetic Effect ◽

Electrochemical Immunosensor ◽

Quantitative Detection ◽

Ferroferric Oxide ◽

Reduced Graphene

A novel nonenzymatic electrochemical immunosensor was fabricated for quantitative detection of [Formula: see text]-fetoprotein (AFP). The immunosensor was constructed by modifying gold electrode with electrochemical reduction of graphene oxide-carboxyl multi-walled carbon nanotube composites (ERGO–CMWCNTs) and electrodeposition of gold nanoparticles (AuNPs) for effective immobilization of primary antibody (Ab[Formula: see text]. Ferroferric oxide–manganese dioxide–reduced graphene oxide nanocomposites (Fe3O4@MnO2–rGO) were designed as labels for signal amplification. On one hand, the excellent electroconductivity and outstanding electron transfer capability of ERGO–CMWCNTs/AuNPs improved the sensitivity of the immunosensor. On the other hand, introduction of rGO could not only increase the specific surface area for immobilization of secondary antibody (Ab[Formula: see text] but also build a synergetic effect to reinforce the electrocatalytic properties of catalysts. Fe3O4@MnO2–rGO nanocomposites were characterized by scanning electron microscope, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Using AFP as a model analyte, the proposed sandwich-type electrochemical immunosensor exhibited a wide linear range of 0.01–50[Formula: see text][Formula: see text] with a low detection limit of 5.8[Formula: see text][Formula: see text]. Moreover, the Fe3O4@MnO2–rGO-based peroxidase mimetic system displayed an excellent analytical performance with low cost, satisfactory reproducibility and high selectivity, which could be further extended for detecting other disease-related biomarkers.

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SYNTHESIS AND CHARACTERIZATION OF Au NANOPARTICLES/REDUCED GRAPHENE OXIDE NANOCOMPOSITE: A FACILE AND ECO-FRIENDLY APPROACH

NANO ◽

10.1142/s1793292014500313 ◽

2014 ◽

Vol 09 (03) ◽

pp. 1450031

Author(s):

MEILING ZOU ◽

HAN ZHU ◽

PAN WANG ◽

SHIYONG BAO ◽

MINGLIANG DU ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Au Nanoparticles ◽

Epigallocatechin Gallate ◽

Chloroauric Acid ◽

Mixed Solution ◽

Atomic Force ◽

Transmission Electron ◽

Reduced Graphene

In this paper, epigallocatechin gallate (EGCG) was used as a green reductant both for the fabrication of soluble reduced graphene oxide (rGO) and the synthesis of Au nanoparticles/rGO nanocomposite. Fourier transform infrared (FTIR) spectra confirmed the efficient removal of the oxygen-containing groups in graphene oxide (GO) through the reduction act of EGCG. Au nanoparticles ( AuNPs ) were anchored onto the rGO sheets by heating the mixed solution of rGO and chloroauric acid at 65°C using EGCG as reductant. Transmission electron microscopy (TEM), atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the resulting nanocomposite. Due to the chelating effect of polyhydroxy EGCG, AuNPs with diameters of ~20–50 nm were stably decorated onto both sides of the rGO sheets. Because this reduction method avoids the use of toxic reagents, AuNPs /rGO nanocomposite would be eco-friendly, and it might be useful not only for electronic devices but also for biocompatible materials in the future applications.

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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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Reduced Graphene Oxide/TiO2 Nanocomposite: From Synthesis to Characterization for Efficient Visible Light Photocatalytic Applications

Catalysts ◽

10.3390/catal8120598 ◽

2018 ◽

Vol 8 (12) ◽

pp. 598 ◽

Cited By ~ 19

Author(s):

Elena Rommozzi ◽

Marco Zannotti ◽

Rita Giovannetti ◽

Chiara D’Amato ◽

Stefano Ferraro ◽

...

Keyword(s):

Graphene Oxide ◽

Visible Light ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Thermal Reduction ◽

Alizarin Red S ◽

Alizarin Red ◽

Force Microscopy ◽

Reduced Graphene ◽

Visible Light Photocatalytic

In this study, a green and facile thermal reduction of graphene oxide using an eco-friendly system of d-(+)-glucose and NH4OH for the preparation of reduced graphene oxide was described. The obtained reduced graphene oxide dispersion was characterized by SEM, Dynamic Light Scattering, Raman and X-Ray Photoelectron Spectroscopy. TiO2 nanoparticles and reduced graphene oxide nanocomposites were successively prepared and used in the preparation of heterogeneous photocatalysts that were characterized by Atomic Force Microscopy and Photoluminescence Spectroscopy and subsequently tested as visible light photocatalysts for the photodegradation of Alizarin Red S in water as target pollutant. Obtained results of photocatalytic tests regarding the visible light photocatalytic degradation of Alizarin Red S demonstrated that the use of reduced graphene oxide in combination with TiO2 led to a significant improvement for both adsorption of Alizarin Red S on the catalyst surface and photodegradation efficiencies when compared to those obtained with not doped TiO2.

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Electrochemical Response of Platinum Ultrathin Layer Formed by Pulsed Laser Deposition

International Journal of Electrochemistry ◽

10.4061/2011/463281 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Takeshi Ito ◽

Satoru Kaneko ◽

Masayuki Kunimatsu ◽

Yasuo Hirabayashi ◽

Masayasu Soga ◽

...

Keyword(s):

Pulsed Laser Deposition ◽

Photoelectron Spectroscopy ◽

Low Cost ◽

Pulsed Laser ◽

Metal Electrode ◽

Laser Deposition ◽

Force Microscopy ◽

Atomic Force ◽

Microscopy Images ◽

Ultrathin Layer

Ultrathin layer of platinum (ULPt) was deposited on glassy carbon (GC) substrate by using pulsed laser deposition (PLD) method, and electrochemical properties of the ULPt were discussed. The deposition was simply performed at room temperature with short deposition time. Atomic force microscopy and scanning electron microscopy images showed the flat surface of the ULPt. X-ray photoelectron spectroscopy (XPS) characterized the ULPt in the Pt(0) state, and biding energy of ULPt was positively shifted. These results indicated that nanostructure of Pt thin layer was formed. The electrochemical activity of the prepared ULPt on GC substrate was superior to a bulk Pt electrode regarding the potential and the magnitude of current on oxidizing hydrogen peroxide. This fast and easily prepared low-cost electrode had the potential to replace a conventional bulk metal electrode.

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