Graphene oxide is a compound produced by treating graphite with strong oxidizing agents. It consists of carbon, oxygen, and hydrogen atoms arranged in a layered structure similar to graphite. Graphene oxide can be dispersed into single-atom thick sheets in water and other solvents. It has unique optical, thermal, and mechanical properties that make it useful for applications such as composite materials, energy storage, and biomedical devices. Reduction of graphene oxide is needed to recover its electrical conductivity by removing oxygen groups and restoring the honeycomb lattice structure.
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Graphene Presentation
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Graphene Presentation
This presentation contains various aspects of Graphene like synthesis techniques, characterization, commercialization, mechanical and electrical properties and present and future application.
PRESENTATION OUTLINE
Introduction,History of Nanotechnology,What is Nanotechnology, Definition of Nano,History of Graphene,Graphene,Why Nanotechnology,Size of Nanotechnology,What is Graphene, Properties of Graphene,Graphene Structure,Types of Graphene ,Synthesize Graphene,Applications,Conclusions,References
It's simple to understand the synthesis. Hydrothermal method is a chemical reaction in water in a sealed pressure vessel, which is in fact a type of reaction at both high temperature and pressure.
GRAPHENE SYNTHESIS AND ITS APPLICATIONS TERM PAPER PRESENTATIONAman Gupta
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Graphene synthesis process and its current and future applications explained in brief
Fabrication and Characterization of 2D Titanium Carbide MXene NanosheetsBecker Budwan
Typically, 2D free-standing crystals exhibit different properties from those of 3D counterparts. In this work, 2D nanosheets of Ti3C2 are synthesized by the room temperature exfoliation of Ti3AlC2 in hydrofluoric acid. Al is extracted from Ti3AlC2 and a new 2D material that we call MXene is formed to emphasize its graphene-like morphology. The treated powders can be used in the fabrication of Li-ion batteries and capacitors. A NSEM image of the treated powder shows the influence of HF treatment on the basal planes. Furthermore, XRD results shows the broadening of the peaks and loss of diffraction signal in the out-of-plane direction owing to exfoliation.
Optical band gap measurement by diffuse reflectance spectroscopy (drs)Sajjad Ullah
Introduction to Optical band gap measurement
by electronic spectroscopy and diffuse reflectance spectroscopy (DRS) with comparison of the results obtained suing different equation and measurement techniques.
The role of scattering in extinction of light as it passes through media is briefly discussed.
Graphene, the amazing two-dimensional carbon nanomaterial, has attracted extensive interest in recent years and emerged as the most intensively studied material [1]. In 2004, Geim and Nosovelov at Manchester University successfully isolated single layer graphene by the mechanical cleavage of graphite crystal [2]. This ‘‘thinnest’’ known material exhibits extraordinary electronic, chemical, mechanical, thermal and optical properties which bestowed graphene as a miracle material of the 21st Century. From applicative perspectives, graphene holds a great promise with the potential to be used as energy-storage materials, in nanoelectronics, in catalysis, biomedical, in polymer composites and many more.
Graphite oxide (GO) formerly called graphitic oxide or graphitic acid, is a compound of carbon, oxygen, and hydrogen in variable ratios, obtained by treating graphite with strong oxidizers and acids for resolving of extra metals. The maximally oxidized bulk product is a yellow solid with C:O ratio between 2.1 and 2.9, that retains the layer structure of graphite but with a much larger and irregular spacing.
Structure proposed in 1998 with functional groups. A: Epoxy bridges, B: Hydroxyl groups, C: Pairwise carboxyl groups.
The bulk material spontaneously disperses in basic solutions or can be dispersed by sonication in polar solvents to yield monomolecular sheets, known as graphene oxide by analogy to graphene, the single-layer form of graphite. Graphene oxide sheets have been used to prepare strong paper-like materials, membranes, thin films, and composite materials. Initially, graphene oxide attracted substantial interest as a possible intermediate for the manufacture of graphene. The graphene obtained by reduction of graphene oxide still has many chemical and structural defects which is a problem for some applications but an advantage for some others .Graphite oxide was first prepared by Oxford chemist Benjamin C. Brodie in 1859, by treating graphite with a mixture of potassium chlorate and fuming nitric acid.He reported synthesis of "paper-like foils" with 0.05 mm thickness. In 1957 Hummers and Offeman developed a safer, quicker, and more efficient process called Hummers' method, using a mixture of sulfuric acid H2SO4, sodium nitrate NaNO3, and potassium permanganate KMnO4, which is still widely used, often with some modifications. Largest monolayer GO with highly intact carbon framework and minimal residual impurity concentrations can be synthesized in inert containers using highly pure reactants and solvents.
Graphite oxides demonstrate considerable variation of properties depending on the degree of oxidation and the synthesis method. For example, the temperature point of explosive exfoliation is generally higher for graphite oxide prepared by the Brodie method compared to Hummers graphite oxide, the difference is up to 100 degrees with the same heating rates.Hydration and solvation properties of Brodie and Hummers graphite oxides are also remarkably different.Recently a mixture of H2SO4 and KMnO4 has been used to cut open carbon nanotubes lengthwise, resulting in microscopic flat ribbons of graphene, a few atoms wide, with the edges "capped" by oxygen atoms (=O) or hydroxyl groups (-OH).
Graphite (graphene) oxide has also been prepared by using a "bottom-up" synthesis method (Tang-Lau method) in which the sole source is glucose, the process is safer, simpler, and more environmentally friendly compared to traditionally "top-down" method, in which strong oxidizers are involved. Another important advantage of the Tang-Lau method is the control of thickness, ranging from monolayer to multilayers, by adjusting growth parameters.
This presentation contains various aspects of Graphene like synthesis techniques, characterization, commercialization, mechanical and electrical properties and present and future application.
PRESENTATION OUTLINE
Introduction,History of Nanotechnology,What is Nanotechnology, Definition of Nano,History of Graphene,Graphene,Why Nanotechnology,Size of Nanotechnology,What is Graphene, Properties of Graphene,Graphene Structure,Types of Graphene ,Synthesize Graphene,Applications,Conclusions,References
It's simple to understand the synthesis. Hydrothermal method is a chemical reaction in water in a sealed pressure vessel, which is in fact a type of reaction at both high temperature and pressure.
GRAPHENE SYNTHESIS AND ITS APPLICATIONS TERM PAPER PRESENTATIONAman Gupta
For free download Subscribe to https://www.youtube.com/channel/UCTfiZ8qwZ_8_vTjxeCB037w and Follow https://www.instagram.com/fitrit_2405/ then please contact +91-9045839849 over WhatsApp.
Graphene synthesis process and its current and future applications explained in brief
Fabrication and Characterization of 2D Titanium Carbide MXene NanosheetsBecker Budwan
Typically, 2D free-standing crystals exhibit different properties from those of 3D counterparts. In this work, 2D nanosheets of Ti3C2 are synthesized by the room temperature exfoliation of Ti3AlC2 in hydrofluoric acid. Al is extracted from Ti3AlC2 and a new 2D material that we call MXene is formed to emphasize its graphene-like morphology. The treated powders can be used in the fabrication of Li-ion batteries and capacitors. A NSEM image of the treated powder shows the influence of HF treatment on the basal planes. Furthermore, XRD results shows the broadening of the peaks and loss of diffraction signal in the out-of-plane direction owing to exfoliation.
Optical band gap measurement by diffuse reflectance spectroscopy (drs)Sajjad Ullah
Introduction to Optical band gap measurement
by electronic spectroscopy and diffuse reflectance spectroscopy (DRS) with comparison of the results obtained suing different equation and measurement techniques.
The role of scattering in extinction of light as it passes through media is briefly discussed.
Graphene, the amazing two-dimensional carbon nanomaterial, has attracted extensive interest in recent years and emerged as the most intensively studied material [1]. In 2004, Geim and Nosovelov at Manchester University successfully isolated single layer graphene by the mechanical cleavage of graphite crystal [2]. This ‘‘thinnest’’ known material exhibits extraordinary electronic, chemical, mechanical, thermal and optical properties which bestowed graphene as a miracle material of the 21st Century. From applicative perspectives, graphene holds a great promise with the potential to be used as energy-storage materials, in nanoelectronics, in catalysis, biomedical, in polymer composites and many more.
Graphite oxide (GO) formerly called graphitic oxide or graphitic acid, is a compound of carbon, oxygen, and hydrogen in variable ratios, obtained by treating graphite with strong oxidizers and acids for resolving of extra metals. The maximally oxidized bulk product is a yellow solid with C:O ratio between 2.1 and 2.9, that retains the layer structure of graphite but with a much larger and irregular spacing.
Structure proposed in 1998 with functional groups. A: Epoxy bridges, B: Hydroxyl groups, C: Pairwise carboxyl groups.
The bulk material spontaneously disperses in basic solutions or can be dispersed by sonication in polar solvents to yield monomolecular sheets, known as graphene oxide by analogy to graphene, the single-layer form of graphite. Graphene oxide sheets have been used to prepare strong paper-like materials, membranes, thin films, and composite materials. Initially, graphene oxide attracted substantial interest as a possible intermediate for the manufacture of graphene. The graphene obtained by reduction of graphene oxide still has many chemical and structural defects which is a problem for some applications but an advantage for some others .Graphite oxide was first prepared by Oxford chemist Benjamin C. Brodie in 1859, by treating graphite with a mixture of potassium chlorate and fuming nitric acid.He reported synthesis of "paper-like foils" with 0.05 mm thickness. In 1957 Hummers and Offeman developed a safer, quicker, and more efficient process called Hummers' method, using a mixture of sulfuric acid H2SO4, sodium nitrate NaNO3, and potassium permanganate KMnO4, which is still widely used, often with some modifications. Largest monolayer GO with highly intact carbon framework and minimal residual impurity concentrations can be synthesized in inert containers using highly pure reactants and solvents.
Graphite oxides demonstrate considerable variation of properties depending on the degree of oxidation and the synthesis method. For example, the temperature point of explosive exfoliation is generally higher for graphite oxide prepared by the Brodie method compared to Hummers graphite oxide, the difference is up to 100 degrees with the same heating rates.Hydration and solvation properties of Brodie and Hummers graphite oxides are also remarkably different.Recently a mixture of H2SO4 and KMnO4 has been used to cut open carbon nanotubes lengthwise, resulting in microscopic flat ribbons of graphene, a few atoms wide, with the edges "capped" by oxygen atoms (=O) or hydroxyl groups (-OH).
Graphite (graphene) oxide has also been prepared by using a "bottom-up" synthesis method (Tang-Lau method) in which the sole source is glucose, the process is safer, simpler, and more environmentally friendly compared to traditionally "top-down" method, in which strong oxidizers are involved. Another important advantage of the Tang-Lau method is the control of thickness, ranging from monolayer to multilayers, by adjusting growth parameters.
Progress in Synthesis of Graphene using CVD, Its Characterization and Challen...paperpublications3
Abstract: Diamond and Graphite both are natural allotropes of carbon. Graphene is a substance composed of sp2 hybridized carbon atoms that are similar to graphite and arranged in a regular hexagonal pattern. Graphene has astounding physical properties such as high electronic conductivity, excellent mechanical strength and thermal stability. It is capable to maintain its strength up to 3,600°C. It is transparent, high super hydrophobicity at nanometer scale , 100 times stronger than steel with high current density. These unique properties make graphene an interesting candidate for a number of applications currently under development, as for instance Li-ion batteries, transparent touch screens, light weight aircrafts or transistors.
Amongst the synthesis techniques, chemical vapor deposition has proved promising result for advance devices and for numerous applications where high-quality graphene films, High purity, fined grained and low structural defects film is required. CVD process is normally conducted below the atmospheric pressure and relatively lower temperatures , less than 1000°C. Pressure of LPCVD is 10-1000 Pascals.
Keywords: CVD, Graphene, Graphite, Graphene sheets..
Title: Progress in Synthesis of Graphene using CVD, Its Characterization and Challenges: A Review
Author: Sakshi Rana, Harminder Singh
International Journal of Recent Research in Electrical and Electronics Engineering (IJRREEE)
ISSN 2349-7815
Paper Publications
Graphene: the world's first 2D material. Since graphene's isolation in 2004, it has captured the attention of scientists, researchers, and industry worldwide.
This presentation is prepared in view of engineering chemistry syllabus. It is useful for Engineering, Sciences and their research to understand basics of chemistry.
Characteristics and applications of graphenealfachemistry
As a new type of nanomaterials with the most thin, the maximum intensity and most conductive conductivity, graphene is known as "black gold" and "king of new materials".
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
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CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
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Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
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When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
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Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
2. A modern material with unique
physical and electrical properties
that could reshape our future.
3. Graphite oxide, formerly called graphitic oxide or graphitic
acid, is a compound of carbon, oxygen, and hydrogen ,
obtained by treating graphite with strong oxidizers.
The bulk material disperses in basic solutions to yield
monomolecular sheets, known as graphene oxide by analogy
to graphene, the single-layer form of graphite.
INTRODUCTION
5. Introduction
Graphene can be described as a
one-atom thick layer of graphite.
It is the basic structural element of
other allotropes, including graphite,
charcoal, carbon nanotubes and
fullerenes.
Graphene is the strongest, thinnest
material known to exist.
Graphene is an atomic-scale honeycomb
lattice made of carbon atoms.
6. Graphene is a 2D crystal of carbon
atoms, arranged in a honeycomb
lattice
Each carbon atom is sp2 hybridized
and it is bound to its three
neighbors.
7. History
One of the very first patents pertaining to the production of
graphene was filed in October, 2002 entitled, "Nano-scaled
Graphene Plates“.
Two years later, in 2004 Andre Geim and Kostya Novoselov at
University of Manchester extracted single-atom-thick crystallites
from bulk graphite
Geim and Novoselov received several awards for their pioneering
research on graphene, notably the 2010 Nobel Prize in Physics.
8. Structure
Graphene is a 2-dimensional network of carbon atoms.
These carbon atoms are bound within the plane by strong bonds into a
honeycomb array comprised of six-membered rings.
By stacking of these layers on top of each other, the well known 3-
dimensional graphite crystal is formed.
It is a basic building block for graphitic materials of all other
dimensionalities.
It can be wrapped up into 0D fullerenes, rolled into 1D nanotubes or
stacked into 3D graphite.
Thus, graphene is nothing else than a single graphite layer.
9.
10. Chemical Properties
Graphene is chemically the most reactive form of
carbon.
Only form of carbon (and generally all solid materials)
in which each single atom is in exposure for chemical
reaction from two sides (due to the 2D structure).
Carbon atoms at the edge of graphene sheets have
special chemical reactivity.
graphene burns at very low temperature (e.g., 350 °C).
Graphene has the highest ratio of edgy carbons (in
comparison with similar materials such as carbon
nanotubes).
Graphene is commonly modified with oxygen- and
nitrogen-containing functional groups
11. Electronic Properties
It is a zero-overlap semimetal (with both holes and electrons as charge
carriers) with very high electrical conductivity.
Electrons are able to flow through graphene more easily than through even
copper.
The electrons travel through the graphene sheet as if they carry no mass, as
fast as just one hundredth that of the speed of light.
High charge carrier mobility, for which values of 10,000 cm2/Vs, in some cases
even 200,000 cm2/Vs were reported.
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12. In an insulator or semiconductor, an electron bound to an atom can break free only
if it gets enough energy from heat or passing photon to jump the ‘band gap’.
But in graphene the gap is infinitesimal. This is the main reason why graphene’s
electron can move easily and very fast.
13. Mechanical Properties
To calculate the strength of graphene,
scientists used a technique called Atomic
Force Microscopy.
It was found that graphene is harder than
diamond and about 300 times harder than
steel.
The tensile strength of graphene exceeds
1 TPa.
It is stretchable up to 20% of its initial
length.
14. It is expected that graphene’s
mechanical properties will find
applications into making a
new generation of super
strong composite materials
and along combined with its
optical properties, making
flexible displays.
15. Thermal Properties
Graphene is a perfect thermal conductor
Its thermal conductivity is much higher than all the other carbon
structures as carbon nanotubes, graphite and diamond (> 5000
W/m/K) at room temperature
Graphite, the 3 D version of graphene, shows a thermal
conductivity about 5 times smaller (1000 W/m/K)
The ballistic thermal conductance of graphene is isotropic, i.e.
same in all directions
16. The material's high
electron mobility and high
thermal conductivity
could lead to chips that
are not only faster but
also better at dissipating
heat.
This schematic shows a
three-dimensional stacked
chip with layers of
graphene acting as heat
spreaders.
17. Optical Properties
Graphene, despite it is only 1 atom
thick, is still visible to the naked
eye.
Due to its unique electronic
properties, it absorbs a high 2.3%
of light that passes through it.
Photograph of graphene in transmitted light. This one-atom-
thick crystal can be seen with the naked eye.
19. Graphene Oxide , the monomolecular sheets of graphite oxide is
a compound of carbon, oxygen, and hydrogen in variable ratios,
obtained by treating graphite with strong oxidizers.
Graphene oxide sheets have been used to prepare a strong
paper-like material, and have recently attracted substantial
interest as a possible intermediate for the manufacture of
graphene.
GRAPHENE OXIDE
20. Graphene oxide was first prepared by Oxford chemist Benjamin
C. Brodie in 1859, by treating graphite with a mixture
of potassium chlorate and fuming nitric acid.
In 1957 Hummers and Offeman developed a safer, quicker, and
more efficient process called The Hummers' Method, using a
mixture of sulfuric acid (H2SO4), sodium nitrate (NaNO3),
and potassium permanganate (KMnO4) which is still used.
A Little History…
21. Graphene oxide (GO) has also been prepared by using a "bottom-
up" synthesis method (Tang-Lau method) in which the sole source
is glucose, the process is safer, simpler, and more environmentally
friendly.
A Little History…
22. The structure and properties of graphite oxide depend on
particular synthesis method and degree of oxidation. It typically
preserves the layer structure of the parent graphite.
Besides oxygen epoxide groups (bridging oxygen atoms), other
functional groups experimentally found are : carbonyl (C=O),
hydroxyl (-OH) and phenol(PhOH).
Structure
23. Graphene oxide layers are about 1.1 ± 0.2 nm thick.
Scanning tunneling microscopy shows the presence of local
regions where oxygen atoms are arranged in a rectangular
pattern.
The edges of each layer are terminated with carboxyl and
carbonyl groups.
Structure
24. Structure proposed in 1998 with
functional groups.
A: Epoxy bridges,
B: Hydroxyl groups,
C: Pairwise carboxyl groups
25.
26. XRD, FTIR, Raman, XPS, AFM, TEM, etc. are some common
techniques to characterize Graphene Oxide samples.
Since the distribution of oxygen groups on GO sheets is disperse,
fractionation method using stabilization can be used to
characterize Graphene Oxide sheets.
Characterization
27. (A) Image of fractionated
GO, (B) XRD, (C) Raman,
and (D) FTIR spectra of
GO (black), GOw fraction
(blue), and GOe fraction
(red).
28. Graphite oxides absorb moisture proportionally to humidity and
swells in liquid water.
The amount of water absorbed by graphite oxides depends on
the particular synthesis method and shows a strong temperature
dependence.
Membranes prepared from graphene oxide are vacuum tight and
impermeable to nitrogen and oxygen, but are permeable to water
vapors.
Relation to water
29. Exfoliation of graphene oxide at high temperature.
Exfoliation results in tenfold increase of sample volume and formation of carbon
powder with grains of few graphene layers thickness.
(Exfoliation : to remove the surface of a substance)
30. 1. One of the advantages of the gaphene oxide is its easy
dispersability in water and other organic solvents due to the
presence of the oxygen functionalities.
This helps when mixing the material with ceramic or polymer
matrixes when trying to improve their electrical and
mechanical properties.
Properties
31. 2. Graphene oxide is often described as an electrical
insulator, due to the disruption of its sp2 bonding networks.
In order to recover the honeycomb lattice, and with it the
electrical conductivity, the reduction of the graphene oxide
has to be achieved.
The reduced graphene oxide obtained is more difficult to
disperse.
Properties
32. 3. Functionalization of graphene oxide can fundamentally change
graphene oxide’s properties.
There are many ways in which graphene oxide can be
functionalized, depending on the desired application. For
optoelectronics, biodevices or as a drug-delivery material.
Eg.-It is possible to substitute amines on graphene to increase
the dispersability of chemically modified graphenes in organic
solvents.
Properties
35. 4. It is important to develop an oxidization and reduction process
that is able to separate individual carbon layers and then isolate
them without modifying their structure.
Chemical reduction of graphene oxide is currently seen as the
most suitable method of mass production of graphene.
Properties