Properties of free-standing graphene oxide/silver nanowires films and effects of chemical reduction and gamma irradiation

Fabrication of free-standing reduced graphene oxide (RGO) films by vacuum filtration of graphene oxide aqueous solution through a nanofiber membrane in combination with chemical reduction.

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Caffeine as Nitrogen Source for Reduce Graphene Doping, and Its Functionalization with Silver Nanowires

10.20944/preprints201807.0469.v1 ◽

2018 ◽

Author(s):

Daniel Ramirez-Gonzalez ◽

Jose de Jesus Cruz-Rivera ◽

Hugo Tiznado ◽

Angel Gabriel Rodriguez-Vazquez ◽

Ivan Guillen-Escamilla ◽

...

Keyword(s):

Graphene Oxide ◽

Nitrogen Source ◽

Silver Nanowires ◽

Chemical Reduction ◽

Low Cost ◽

Nitrogen Doped ◽

Nanowires Growth ◽

Nitrogen Doped Graphene ◽

Doped Graphene ◽

Ft Ir

In this work, we propose an easy and a low cost method for the synthesis of Nitrogen-Doped Graphene NDG and its silver nanowires NW functionalization NWGN. The synthesis was performed using the improved graphene oxide method, chemical reduction of graphene oxide in the presence of caffeine as green nitrogen source and the subsequently the silver nanowires growth in the surface, by the chemical reductions salts in the presence of NG. Achieving a homogeneous growing (coating) of graphene sheets. The samples were analyzed using conventional characterization techniques: SEM-EDX, XRD, FT-IR, RAMAN, TEM, HRTEM, STEM and XPS.

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Facile synthesis of flexible graphene–silver composite papers with promising electrical and thermal conductivity performances

RSC Advances ◽

10.1039/c4ra05176a ◽

2014 ◽

Vol 4 (64) ◽

pp. 34156-34160 ◽

Cited By ~ 11

Author(s):

Sheng-Yun Huang ◽

Kai Zhang ◽

Matthew M. F. Yuen ◽

Xian-Zhu Fu ◽

Rong Sun ◽

...

Keyword(s):

Thermal Conductivity ◽

Graphene Oxide ◽

Chemical Reduction ◽

Facile Synthesis ◽

Free Standing ◽

Silver Composite ◽

Composite Paper

Free-standing and flexible graphene–silver (GE–Ag) composite paper has been successfully fabricated through an evaporation of graphene oxide–AgNO3 aqueous aerosol followed by a chemical reduction.

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Preparation for Graphene Coated Polyvinyl Alcohol Based Conductive Fiber Containing Silver Nanowires

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.807.171 ◽

2019 ◽

Vol 807 ◽

pp. 171-175

Author(s):

Chao Xiao ◽

Xi Ke Xiong ◽

Jun Sun ◽

Li Xing Dai

Keyword(s):

Electrical Conductivity ◽

Graphene Oxide ◽

Synergistic Effect ◽

Polyvinyl Alcohol ◽

Silver Nanowires ◽

Chemical Reduction ◽

Fiber Surface ◽

Coated Fiber ◽

Conductive Fiber ◽

Pva Fiber

Graphene oxide (GO) coated fiber via deposition of GO sheets on polyvinyl alcohol (PVA) fiber containing silver nanowires (AgNWs) was fabricated, and chemical reduction for GO on the fiber surface was carried out to obtain reduced GO (rGO) coated PVA-AgNWs (rGO/PVA-AgNWs) fiber. The results showed that the rGO sheets were closely adhered on the surface of fiber, the electrical conductivity of the fiber increased with coating times of GO, and the conductivity was high up to 2.05×10-3 S/m when GO was coated 3 times on the fiber and reduced. The synergistic effect of rGO and AgNWs for the conductivity was also clearly indicated.

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Low Surface Roughness Graphene Oxide Film Reduced with Aluminum Film Deposited by Magnetron Sputtering

Nanomaterials ◽

10.3390/nano11061428 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1428

Author(s):

Xiaowei Fan ◽

Xuguo Huai ◽

Jie Wang ◽

Li-Chao Jing ◽

Tao Wang ◽

...

Keyword(s):

Surface Roughness ◽

Electron Transfer ◽

Graphene Oxide ◽

Magnetron Sputtering ◽

Chemical Reduction ◽

Graphene Film ◽

Conductivity Measurement ◽

Electrical Conductivity Measurement ◽

Vis Spectroscopy ◽

Hcl Solution

Graphene film has wide applications in optoelectronic and photovoltaic devices. A novel and facile method was reported for the reduction of graphene oxide (GO) film by electron transfer and nascent hydrogen produced between aluminum (Al) film deposited by magnetron sputtering and hydrochloric acid (HCl) solution for only 5 min, significantly shorter than by other chemical reduction methods. The thickness of Al film was controlled utilizing a metal detection sensor. The effect of the thickness of Al film and the concentration of HCl solution during the reduction was explored. The optimal thickness of Al film was obtained by UV-Vis spectroscopy and electrical conductivity measurement of reduced GO film. Atomic force microscope images could show the continuous film clearly, which resulted from the overlap of GO flakes, the film had a relatively flat surface morphology, and the surface roughness reduced from 7.68 to 3.13 nm after the Al reduction. The film sheet resistance can be obviously reduced, and it reached 9.38 kΩ/sq with a high transmittance of 80% (at 550 nm). The mechanism of the GO film reduction by electron transfer and nascent hydrogen during the procedure was also proposed and analyzed.

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Free-standing reduced graphene oxide (rGO) membrane for salt-rejecting solar desalination via size effect

Nanophotonics ◽

10.1515/nanoph-2020-0396 ◽

2020 ◽

Vol 9 (15) ◽

pp. 4601-4608 ◽

Cited By ~ 1

Author(s):

Pengyu Zhuang ◽

Hanyu Fu ◽

Ning Xu ◽

Bo Li ◽

Jun Xu ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Conversion Efficiency ◽

High Salinity ◽

Interlayer Spacing ◽

Structural Instability ◽

Solar Thermal ◽

Free Standing ◽

Solar Desalination ◽

Reduced Graphene

AbstractInterfacial solar vapor generation has revived the solar-thermal-based desalination due to its high conversion efficiency of solar energy. However, most solar evaporators reported so far suffer from severe salt-clogging problems during solar desalination, leading to performance degradation and structural instability. Here, we demonstrate a free-standing salt-rejecting reduced graphene oxide (rGO) membrane serving as an efficient, stable, and antisalt-fouling solar evaporator. The evaporation rate of the membrane reaches up to 1.27 kg m−2 h−1 (solar–thermal conversion efficiency ∼79%) under one sun, out of 3.5 wt% brine. More strikingly, due to the tailored narrow interlayer spacing, the rGO membrane can effectively reject ions, preventing salt accumulation even for high salinity brine (∼8 wt% concentration). With enabled salt-antifouling capability, flexibility, as well as stability, our rGO membrane serves as a promising solar evaporator for high salinity brine treatment.

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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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