Back-to-Back Schottky Diode from Vacuum Filtered and Chemically Reduced Graphene Oxide

<span>This paper presents fabrication of reduced graphene oxide (rGO)/silicon (Si) back-to-back Schottky diode (BBSD) through graphene oxide (GO) thin film formation by vacuum filtration and chemical reduction of the film via ascorbic acid. In order to understand and assess the viability of these two processes, process condition and parameters were varied and analyzed. It was confirmed that the GO film thickness could be controlled by changing GO dispersion volume and concentration. Filtration of 200 ml of 0.4 ppm GO dispersion produced average film thickness of 53 nm. As for the reduction process, long duration was required to produce higher reduction degree. rGO film that underwent two times reduction at before and after transfer process with concentrated ascorbic acid gave the lowest sheet resistance of 3.58 MΩ/sq. In the final part of the paper, result of the BBSD device fabrication and current-voltage characterization were shown. The formed two rGO/Si Schottky junctions in the BBSD gave barrier height of 0.63 and 0.7 eV. The presented results confirmed the viability of fabricating rGO-based device using a simple method and without requirement of sophisticated equipment.</span>

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Formation and Characterization of Copper Nanocube-Decorated Reduced Graphene Oxide Film

Journal of Nanomaterials ◽

10.1155/2017/5702838 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6

Author(s):

M. Z. H. Khan ◽

M. A. Rahman ◽

P. Yasmin ◽

F. K. Tareq ◽

N. Yuta ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Indium Tin Oxide ◽

Chemical Reduction ◽

Device Fabrication ◽

Simple Method ◽

Force Microscopy ◽

Reduced Graphene ◽

Vis Spectroscopy ◽

The Individual

In this study, we present a new approach for the formation and deposition of Cu nanocube-decorated reduced graphene oxide (rGO-CuNCs) nanosheet on indium tin oxide (ITO) electrode using very simple method. Cubic Cu nanocrystals have been successfully fabricated on rGO by a chemical reduction method at low temperature. The morphologies of the synthesized materials were characterized by ultraviolet-visible (UV-vis) spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and atomic force microscopy (AFM). The as-formed CuNCs were found to be homogeneously and uniformly decorated on rGO nanosheets. We demonstrated that the individual rGO sheets can be readily reduced and decorated with CuNCs under a mild condition using L-ascorbic acid (L-AA). Such novel ITO/rGO-CuNCs represent promising platform for future device fabrication and electrocatalytic applications.

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EFFECT OF REDUCTION TIME ON OPTICAL PROPERTIES OF REDUCED GRAPHENE OXIDE

Jurnal Teknologi ◽

10.11113/jt.v79.10432 ◽

2017 ◽

Vol 79 (1-2) ◽

Author(s):

Nur Fatihah Tajul Arifin ◽

Madzlan Aziz

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Chemical Reduction ◽

Reduction Process ◽

The Other ◽

Reduction Time ◽

Reduced Graphene ◽

Graphene Derivatives ◽

Ft Ir ◽

Epoxy Groups

Graphene and its’ derivatives received tremendous attention. The characteristics and properties of graphene made the material suitable to be used in many applications such as polymer composites, transistors and sensors. Graphene oxide (GO) and reduced graphene oxide (rGO) are few examples of graphene derivatives. GO can be synthesized in many ways. In this study, GO was produced via modified Hummer’s method. Meanwhile, sodium borohydride (NaBH4) is chosen as a reductant to further reduce the GO via chemical reduction. The material was characterized using FT-IR, UV-Vis and FESEM to observe the characteristics which occurred during the reduction process. From the FT-IR spectrum it is clearly shown that the carbonyl (C=O) and epoxy groups were eliminated on rGO. On the other hand, the band gap value of rGO reduced gradually as the reduction time increase. Besides that, the morphology of GO and rGO was also compared under the magnification of 2500x.

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Magnetization of Ultraviolet-Reduced Graphene Oxide Flakes in Composites Based on Polystyrene

Materials ◽

10.3390/ma14102519 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2519

Author(s):

Alexander N. Ionov ◽

Mikhail P. Volkov ◽

Marianna N. Nikolaeva ◽

Ruslan Y. Smyslov ◽

Alexander N. Bugrov

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Reduction Process ◽

X Ray Diffraction ◽

Mesoscopic Structure ◽

Reduced Graphene ◽

Study Results ◽

Edge Defects ◽

Mesoscopic Level ◽

Ferromagnetic Hysteresis

This work presents our study results of the magnetization of multilayer UV-reduced graphene oxide (UV-rGO), polymer matrix (polystyrene), and a conjugated composite based on them. The mesoscopic structure of the composites synthesized in this work was studied by such methods as X-ray diffraction, SEM, as well as NMR-, IR- and Raman spectroscopy. The magnetization of the composites under investigation and their components was measured using a vibrating-sample magnetometer. It has been shown that the UV-reduction process leads to the formation of many submicron holes distributed inside rGO flakes, which can create edge defects, causing possibly magnetic order in the graphite samples under investigation on the mesoscopic level. This article provides an alternative explanation for the ferromagnetic hysteresis loop in UV-rGO on the base of superconductivity type-II.

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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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Chemically reduced graphene oxide-coated knitted fabric imparted conductivity and outstanding hydrophobicity

Textile Research Journal ◽

10.1177/0040517521995471 ◽

2021 ◽

pp. 004051752199547

Author(s):

Min Hou ◽

Xinghua Hong ◽

Yanjun Tang ◽

Zimin Jin ◽

Chengyan Zhu ◽

...

Keyword(s):

Electrical Conductivity ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Chemical Reduction ◽

Knitted Fabric ◽

Mesh Structure ◽

Reduced Graphene ◽

Chemically Reduced Graphene Oxide ◽

Modified Hummers Method

Functionalized knitted fabric, as a kind of flexible, wearable, and waterproof material capable of conductivity, sensitivity and outstanding hydrophobicity, is valuable for multi-field applications. Herein, the reduced graphene oxide (RGO)-coated knitted fabric (polyester/spandex blended) is prepared, which involves the use of graphite oxide (GO) by modified Hummers method and in-situ chemical reduction with hydrazine hydrate. The treated fabric exhibits a high electrical conductivity (202.09 S/cm) and an outstanding hydrophobicity (140°). The outstanding hydrophobicity is associated with the morphology of the fabric and fiber with reference to pseudo-infiltration. These properties can withstand repeated bending and washing without serious deterioration, maintaining good electrical conductivity (35.70 S/cm) and contact angle (119.39°) after eight standard washing cycles. The material, which has RGO architecture and continuous loop mesh structure, can find wide use in smart garment applications.

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