A simple low-cost method to prepare gel electrolytes incorporating graphene oxide with increased ionic conductivity and electrochemical stability

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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Low-cost synthesis of high quality graphene oxide with large electrical and thermal conductivities

Materials Letters ◽

10.1016/j.matlet.2021.129649 ◽

2021 ◽

pp. 129649

Author(s):

Shalik Ram Joshi ◽

Jaekyo Lee ◽

Gun-Ho Kim

Keyword(s):

Graphene Oxide ◽

Low Cost ◽

High Quality ◽

Thermal Conductivities

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Self-supported 3D reduced graphene oxide for solid-phase extraction: An efficient and low-cost sorbent for environmental contaminants in aqueous solution

Talanta ◽

10.1016/j.talanta.2021.122750 ◽

2021 ◽

pp. 122750

Author(s):

Raimara de Souza Gomes ◽

Anderson Thesing ◽

Jacqueline Ferreira Leite Santos ◽

Andreia Neves Fernandes

Keyword(s):

Aqueous Solution ◽

Graphene Oxide ◽

Solid Phase Extraction ◽

Reduced Graphene Oxide ◽

Solid Phase ◽

Low Cost ◽

Environmental Contaminants ◽

Phase Extraction ◽

Reduced Graphene

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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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Graphene oxide-based rechargeable respiratory masks

Oxford Open Materials Science ◽

10.1093/oxfmat/itab003 ◽

2020 ◽

Vol 1 (1) ◽

Author(s):

Stelbin Peter Figerez ◽

Sudeshna Patra ◽

G Rajalakshmi ◽

Tharangattu N Narayanan

Keyword(s):

Graphene Oxide ◽

Polyvinylidene Fluoride ◽

Occupational Safety ◽

Low Cost ◽

Triboelectric Nanogenerator ◽

Layer System ◽

Retention Capacity ◽

Simple Modification ◽

Nonwoven Fabrics ◽

Mask Design

Abstract Respiratory masks having similar standards of ‘N95’, defined by the US National Institute for Occupational Safety and Health, will be highly sought after, post the current COVID-19 pandemic. Here, such a low-cost (∼$1/mask) mask design having electrostatic rechargeability and filtration efficiency of >95% with a quality factor of ∼20 kPa−1 is demonstrated. This filtration efficacy is for particles of size 300 nm. The tri-layer mask, named PPDFGO tri, contains nylon, modified polypropylene (PPY), and cotton nonwoven fabrics as three layers. The melt-spun PPY, available in a conventional N95 mask, modified with graphene oxide and polyvinylidene fluoride mixture containing paste using a simple solution casting method acts as active filtration layer. The efficacy of this tri-layer system toward triboelectric rechargeability using small mechanical agitations is demonstrated here. These triboelectric nanogenerator (TENG)-assisted membranes have high electrostatic charge retention capacity (∼1 nC/cm2 after 5 days in ambient condition) and high rechargeability even in very humid conditions (>80% RH). A simple but robust permeability measurement set up is also constructed to test these TENG-based membranes, where a flow rate of 30–35 L/min is maintained during the testing. Such a simple modification to the existing mask designs enabling their rechargeability via external mechanical disturbances, with enhanced usability for single use as well as for reuse with decontantamination, will be highly beneficial in the realm of indispensable personal protective equipment.

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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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Thermogravimetric Analysis (TGA) of Graphene Materials: Effect of Particle Size of Graphene, Graphene Oxide and Graphite on Thermal Parameters

C – Journal of Carbon Research ◽

10.3390/c7020041 ◽

2021 ◽

Vol 7 (2) ◽

pp. 41

Author(s):

Farzaneh Farivar ◽

Pei Lay Yap ◽

Ramesh Udayashankar Karunagaran ◽

Dusan Losic

Keyword(s):

Particle Size ◽

Quality Control ◽

Graphene Oxide ◽

Thermogravimetric Analysis ◽

Low Cost ◽

Thermal Parameters ◽

Carbon Decomposition ◽

Size Number ◽

Carbon Combustion ◽

Oxygen Groups

Thermogravimetric analysis (TGA) has been recognized as a simple and reliable analytical tool for characterization of industrially manufactured graphene powders. Thermal properties of graphene are dependent on many parameters such as particle size, number of layers, defects and presence of oxygen groups to improve the reliability of this method for quality control of graphene materials, therefore it is important to explore the influence of these parameters. This paper presents a comprehensive TGA study to determine the influence of different particle size of the three key materials including graphene, graphene oxide and graphite on their thermal parameters such as carbon decomposition range and its temperature of maximum mass change rate (Tmax). Results showed that Tmax values derived from the TGA-DTG carbon combustion peaks of these materials increasing from GO (558–616 °C), to graphene (659–713 °C) and followed by graphite (841–949 °C) The Tmax values derived from their respective DTG carbon combustion peaks increased as their particle size increased (28.6–120.2 µm for GO, 7.6–73.4 for graphene and 24.2–148.8 µm for graphite). The linear relationship between the Tmax values and the particle size of graphene and their key impurities (graphite and GO) confirmed in this study endows the use of TGA technique with more confidence to evaluate bulk graphene-related materials (GRMs) at low-cost, rapid, reliable and simple diagnostic tool for improved quality control of industrially manufactured GRMs including detection of “fake” graphene.

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