Soluble graphene composite with aggregation-induced emission feature: non-covalent functionalization and application in explosive detection

Herein, a soluble graphene-based material exhibiting the aggregation-induced emission (AIE) feature was prepared for the first time via wet chemistry by the chemical reduction of graphene oxide (GO).

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Optical Properties of Composites Based on Graphene Oxide and Polystyrene

Molecules ◽

10.3390/molecules25102419 ◽

2020 ◽

Vol 25 (10) ◽

pp. 2419 ◽

Cited By ~ 1

Author(s):

Malvina Stroe ◽

Mirela Cristea ◽

Elena Matei ◽

Andrei Galatanu ◽

Liviu C. Cotet ◽

...

Keyword(s):

Optical Properties ◽

Graphene Oxide ◽

Degradation Process ◽

Covalent Functionalization ◽

Photo Degradation ◽

Quenching Process ◽

Uva Light ◽

First Time ◽

Pl Quenching ◽

Properties Of Composites

In this work, new optical properties of composites based on polystyrene (PS) microspheres and graphene oxide (GO) are reported. The radical polymerization of styrene in the presence of benzoyl peroxide, pentane and GO induces the appearance of new ester groups in the PS macromolecular chains remarked through an increase in the absorbance of the infrared (IR) band at 1743 cm−1. The decrease in the GO concentration in the PS/GO composites mass from 5 wt.% to 0.5 wt.% induces a diminution in the intensities of the D and G Raman bands of GO simultaneous with a down-shift of the D band from 1351 to 1322 cm−1. These variations correlated with the covalent functionalization of the GO layers with PS. For the first time, the photoluminescent (PL) properties of PS/GO composites are reported. The PS microspheres are characterized by a PL band at 397 nm. Through increasing the GO sheets’ concentration in the PS/GO composite mass from 0.5 wt.% to 5 wt.%, a PS PL quenching process is reported. In addition, in the presence of ultraviolet A (UVA) light, a photo-degradation process of the PS/GO composite having the GO concentration equal to 5 wt.% is demonstrated by the PL studies.

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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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Spontaneous Exfoliation of Large-Sized Graphene Oxide with Low Defect Concentration by Simple Wet Chemistry

Carbon ◽

10.1016/j.carbon.2021.06.009 ◽

2021 ◽

Author(s):

Woo-Jin Lee ◽

Chan-Soo Kim ◽

Seung-Yeol Yang ◽

Dongwook Lee ◽

Yong-Seog Kim

Keyword(s):

Graphene Oxide ◽

Defect Concentration ◽

Wet Chemistry

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Layer by layer assembled functionalized graphene oxide-based polymer brushes for superlubricity on steel-steel tribocontact

Soft Matter ◽

10.1039/d1sm00690h ◽

2021 ◽

Author(s):

Suprakash Samanta ◽

Rashmi Ranjan Sahoo

Keyword(s):

Graphene Oxide ◽

Nucleophilic Addition ◽

Polymer Brushes ◽

Addition Reaction ◽

Layer By Layer ◽

Functionalized Graphene ◽

Covalent Functionalization ◽

Functionalized Graphene Oxide ◽

Nucleophilic Addition Reaction ◽

Branched Polyethylenimine

Present study demonstrates a simple and multistep approach for the preparation of covalent functionalization of chemically prepared graphene oxide (GO) by branched polyethylenimine (PEI) through nucleophilic addition reaction to prepare...

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Versatile Graphene Oxide Nanosheets via Covalent Functionalization and Their Applications

Materials Chemistry Frontiers ◽

10.1039/d1qm00066g ◽

2021 ◽

Author(s):

Minju Park ◽

Namhee Kim ◽

Jiyoung Lee ◽

Minsu Gu ◽

Byeong-Su Kim

Keyword(s):

Graphene Oxide ◽

Two Dimensional ◽

Graphene Oxide Nanosheets ◽

Covalent Functionalization ◽

Graphene Derivatives

Even though many graphene derivatives that are atomically thin two-dimensional structures, such as graphene oxide (GO), have triggered enormous interest in the scientific and industrial communities owing to their easy...

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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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