When the thermal cvd process is carried out in a resistive heating furnace, it is known as. We have performed an experimental investigation on the effects of hydrazine treatment on graphene oxide via a reactionmodel approach. The main difference between graphite oxide and go is, thus, the number of layers. The flow chart for synthesis of go is given in figure 3. Pdf the reduction of graphene oxide with hydrazine. Twentyfive milligrams of the graphene oxide powder was placed in a cup and 200 ml deionized water was then added.
The comparison between two kinds of singlelayer reduced graphene oxide rgo sheets, obtained by reduction of graphene oxide go with the electrochemical method and hydrazine vapor reduction, referred to as ergo and crgo, respectively, is systematically studied. Graphene oxide go and reduced graphene oxide rgo are known to have superior properties for various applications. Comparison of reduction products from graphite oxide and graphene oxide for anode applications in lithiumion batteries and sodiumion batteries yige sun,a,b jie tang,a,b kun zhang,a jinshi yuan,a jing li,a,b daming zhu,c kiyoshi ozawaa and luchang qind hydrazinereduced graphite oxide and graphene oxide were synthesized to compare their. Ruoff a, a department of mechanical engineering and the texas materials institute, the university of texas at austin, one university station c2200, austin, tx 787120292, usa b department of chemistry, inha university, incheon 402751, republic. Reduction agent temperature c duringreduction reduction time helectrical conductivity sm. Go powder thus obtained was dried at room temperature. Green reduction of graphene oxide by ascorbic acid. We prepared hydrazinereduced materials from both graphite oxide go particles, which were not exfoliated, and.
In addition, our calculations suggest that the epoxide reduction by hydrazine may predominantly follow a direct eleyrideal mechanism rather than a langmuirhinshelwood mechanism. Although the chemical structures and reaction mechanisms associated with these n species in reduced graphene oxide are not yet understood, it is thought that the n atoms come from hydrazine during reduction. Chapter 3 synthesis of graphene oxide and reduced graphene oxide. Request pdf hydrazinereduction of graphite and graphene oxide we prepared hydrazinereduced materials from both graphite oxide go particles, which. Hydrazine can be monoprotonated to form various solid salts of the hydrazinium cation n. Here, we compare the deoxygenation efficiency of graphene oxide suspensions by different reductants sodium borohydride, pyrogallol, and vitamin c, in. Aug 14, 2009 in addition, our calculations suggest that the epoxide reduction by hydrazine may predominantly follow a direct eleyrideal mechanism rather than a langmuirhinshelwood mechanism. Reduction agent temperature c during reduction reduction time h electrical conductivity sm. A comparison of the deoxygenation efficiency of graphene oxide suspensions by different method or reductants has been made, revealing that the highest degree of reduction was achieved by thermal reduction and using hydrazine hydrate and hydroxylammonium chloride as a reducing agents. In conventional thermal reduction process, longtime hightemperature treatment in a protecting atmosphere e. Ruoff a, a department of mechanical engineering and the texas materials institute, the university of texas at austin, one university station c2200. As the reduction proceeds, change in colour from brown to black was observed51.
Thermal reduction methods in combination with ultrasonic or laser irradiation go can be reduced by microwaves in combination with thermal reduction chen, 2010. Microwaveassisted thermal reduction of graphene oxide. Preparation and characterization of graphene oxide reduced. The density functional theory method m052x631gd was used to investigate reaction mechanisms for deoxygenation of graphene oxides gos with hydrazine or heat treatment. Chemical reduction of graphene oxide can be used to produce large quantities of reduced graphene oxide for potential application in electronics, optoelectronics, composite materials and energy. Synthesis of aqueous dispersion of graphenes via reduction of. Apr 17, 2019 graphene, a 2d sheet of carbon atoms arranged in a chicken wire pattern, is a fascinating material that boasts many exciting properties like mechanical strength, thermal and electrical conductivity, intriguing optical properties and more.
In the present investigation, go was prepared by exfoliation of graphite using modified hummers method and then reduced using hydrazine hydrate. Reduction was carried out by hydrazine hydrate the weight ratio of hydrazine hydratego 1 at different. Reduction of go with hydrazine hydrate dried graphite oxide 400 mg prepared by a modi. Laurylamineintercalated graphite oxide go is prepared by ultrasonic in the presence of a small amount of hexane and then chemically reduced by hydrazine. Synthesis of graphene oxide and reduced graphene oxide. Pdf graphene has attracted great interest for its excellent mechanical, electrical. Reduced graphene oxide as catalyst for hydrogenation of.
Go was prepared by using improved hummers method whereas the produced go was subjected to chemical reduction with the use of hydrazine hydrate. While hydrazine reduction of graphene oxide platelets pro. In a go dispersion, a few layer flakes and monolayer flakes can be found. In this paper, graphite oxide was prepared from natural flake graphite by hummers method through liquid oxidization, and the reduced graphene oxide was obtained by chemical reduction of graphene oxide using nh 3 h 2 o aqueous solution and hydrazine hydrate. Reduction of graphene oxide was performed as follows. Solvothermal reduction of graphite oxide using alcohols 3 figure 1. The graphene oxide go was converted to reduced graphene oxide rgo by. In the 1960s, hydrazine nh 2 nh 2 was used to chemically reduce thin graphite oxide go particles 1,2. Vitamin c is an ideal substitute for hydrazine in the. Synthesis of graphene oxide and reduced graphene oxide page 70 to exfoliate the layers figure 3.
Comparison on graphite, graphene oxide and reduced. Synthesis of fewlayer graphene sheets via chemical and. Temperature dependence of graphene oxide reduced by hydrazine. Temperature dependence of graphene oxide reduced by. Reducing graphene oxide to produce reduced graphene oxide hitherto referred to as rgo, is an extremely vital process as it has a large impact on the quality of the rgo produced, and therefore will determine how close rgo will come, in terms of structure, to pristine graphene. Efficient reduction of graphene oxide to obtain highquality graphene nanosheets is desirable for energy storage, catalysis, electronics and environmental remediation. The interlayer spacing of laurylamineintercalated go reaches a maximum when the molar ratio of laurylamine and go is 1. The preparation of solutionprocessable graphene from graphite oxide typically involves a hydrazine reduction step, but the use of such a reagent in the largescale implementation of this approach is not desirable due to its high toxicity. Feb 04, 2011 graphene oxide go was successfully prepared by a modified hummers method. Comparison on graphite, graphene oxide and reduced graphene. We prepared hydrazine reduced materials from both graphite oxide go particles, which were not exfoliated, and completely exfoliated individual graphene oxide platelets, and then analyzed their chemical and structural properties by elemental analysis, xps, tga, xrd, and sem. Reduced graphene oxide an overview sciencedirect topics. Advances in microwaveassisted production of reduced graphene.
Synthesis and characterization of reduced graphene oxide rgo. This work compares the properties of go and rgo with graphite. The remarkable structural changes reveals that reduction of graphene oxide from the values of idig ratio that. Hydrazine is the most common and effective reducing agent used to convert graphene oxide go to reduced graphene oxide rgo via hydrothermal treatment. Synthesis and characterization of reduced graphene oxide. Graphene oxide is a form of graphene that includes oxygen. Synthesis, characterization, chemical reduction and. Chemical structures of hydrazinetreated graphene oxide and.
Applications of graphene oxide and reduced graphene oxide. It has been further reduced by hydrazine hydrate by hydrothermal method to form reduced go rgo. By using hydrazine hydrate, the epoxy group in graphite oxide was reduced then the solution of reduced graphite oxide rgo is exfoliated. Although there is no morphology difference between the ergo and crgo films adsorbed on solid substrates observed by. Hydrazinereduction of graphite and graphene oxide sungjin park a,b, jinho an a, jeffrey r. Hydrazinereduction of graphite and graphene oxide article in carbon 499.
The reduction of graphene oxide can be achieved a number of ways through thermal, chemical, or electrochemical methods. Graphene oxide and reduced graphene oxide, product developments for upcoming applications. Raman spectra of go and rgo suggest the formation of dband and gband at 60 and 1590 cm. The reduction effect and mechanism of the asprepared go reduced with hydrazine hydrate at different temperatures and time were characterized by xray photoelectron spectroscopy xps, fourier transform infrared spectroscopy ftir, elemental analysis ea, xray. Advanced chemical reduction of reduced graphene oxide. Frontiers advances in microwaveassisted production of. Oct 16, 2017 graphene oxide go and reduced graphene oxide rgo are known to have superior properties for various applications.
Around the world, research institutions are trying to develop ways to. Chemical structures of hydrazinetreated graphene oxide. The raw material graphite, graphite oxide, and reduced graphene oxide were. We also discuss the generation of various hydrazine derivatives during the reduction of graphene oxide with hydrazine and their potential contribution to lowering the. Graphene oxide m 2g reduced graphene oxide m2g natrual graphite m2g active carbon m2g expanded graphite m g pyrolytic go m g 62. Thermal reduction of graphene oxide 300 600 0 20 40 60 80 100 221 260 temperature c s43 86 40%. Synthesis and characterization of graphene oxide and. Among various methods used for the reduction of graphene oxide go into a purer form of graphene, the thermal reduction method provides a simpler, safer, and economic alternative, compared to other techniques. Ten minutes of magnetic stirring at 200 r pm yielded an inhomo geneous br own suspension. Explosive reduction of graphite oxide by hydrazine vapor at room temperature. Some reported examples of graphene oxide reduction include. Three mechanisms were identified as reducing epoxide groups of go with hydrazine as a reducing agent. Pdf synthesis and characterization of reduced graphene oxide.
A new approach to synthesize graphene is oxidizing graphite powder with a mixture of h 2 so 4 h 3 po 4 acids and potassium permanganate. The filtered paste was dissolved in 100 ml of water. Similarly for carbon nanotube synthesis, catalytic thermal cvd has proved most signi. Three types of laurylamine in go are identified in the intercalated compounds. The reduction of graphite oxide by hydrazine was used be fore the discovery of graphene 83, while the use of hydrazine to prepare chemically derived graphene was. Graphene oxide go was successfully prepared by a modified hummers method. The hydroxyl and carboxylic groups were not readily removed while carbonyl groups reacted with hydrazine to form. Elucidating its reductive capability based on reactionmodel approach chun kiang chua and martin pumera we have performed an experimental investigation on the effects of hydrazine treatment on graphene oxide via a reactionmodel approach.
Additionally, an n component has been found in materials that are produced by reduction of graphene oxide with hydrazine nh 2 nh 2. A new approach to synthesize graphene is oxidizing graphite powder with a. The resulting suspensions were further treated with a. Graphite oxide, graphene oxide and the reduced one. The methods which are capable of producing the highest quality graphene tend to be more complex. Generally, the reduction of go is carried out by chemical approaches using different reductants such as hydrazine and sodium borohydride. Hydrazinereduction of graphite and graphene oxide request pdf. Graphite oxide, graphene oxide and reduced graphene oxide rgo, for some out there who get confused between the three. An effective reduction method is that of placing a graphite oxide paper into a solution of pure hydrazine.
By using hydrazine hydrate, the epoxy group in graphite oxide was reduced then the solution of reduced. Ruoff and coworkers 3 developed the use of hydrazine to reduce individual graphene oxide. After adding poly4styrenesulfonic acid to the aforesaid suspension and stirring for. Synthesis, fabrication of graphene oxide membranes, and. Synthesis of aqueous dispersion of graphenes via reduction. Currently, an improved method for the preparation of graphene oxide was the most common one. Parameters such as reaction time, reaction temperature, and amount of concentration were varied to study the degree of oxidation of graphite to graphene oxide. Chun kiang chua and martin pumera division of chemistry and biological chemistry, school of physical and mathematical sciences, nanyang technological university, singapore 637371, singapore.
The reduction effect and mechanism of the asprepared go reduced with hydrazine hydrate at different temperatures and time were characterized by xray photoelectron spectroscopy xps, fourier transform infrared spectroscopy ftir, elemental analysis ea, xray diffractions xrd, raman spectroscopy and thermo. Potts a, aruna velamakanni a, shanthi murali a, rodney s. Comparative studies on singlelayer reduced graphene oxide. Reduction of go with laser irradiation trusovas, 20, rgo from graphite oxide under ultraviolet irradiation ji, 20, ultraviolet laser. Synthesis, characterization, chemical reduction and biological application of graphene oxide by xiguang gao a thesis presented to the university of waterloo. The solutionprocessable chemical reduction of graphene oxide go is considered as the most favorable method regarding mass production of graphene. We prepared hydrazinereduced materials from both graphite oxide go particles, which were not exfoliated, and completely exfoliated individual graphene oxide platelets, and then analyzed their chemical and structural properties by elemental analysis, xps, tga, xrd, and sem.
Chun kiang chua and martin pumera division of chemistry and biological chemistry, school of physical and mathematical sciences, nanyang technological university, singapore 637371. Reduction of graphite oxide rgo using hydrazine1, 2. Jan 24, 2012 in the 1960s, hydrazine nh 2 nh 2 was used to chemically reduce thin graphite oxide go particles 1,2. Variations in the d values are directly related to the degree of oxidation of the graphite31. Reduction of graphite oxide in the solution of conductive polymer 39 2. Graphene, which has a two dimensional structure consisting of an sp 2 carbon network with a thickness of one atom, is of both fundamental interest and also for a wide range of potential applications due to its excellent mechanical, thermal, and electrical properties. Reducing graphene oxide to produce reduced graphene oxide hitherto referred to as rgo, is an extremely vital process as it has a large impact on the quality of the rgo produced, and therefore will determine how close. Charge transport mechanism of hydrazine hydrate reduced. Chemical reduction of graphene oxide can be used to produce large quantities of reduced.
Reaction mechanisms, product structures, and reaction design xingfa gao, joonkyung jang and shigeru nagase department of theoretical and computational molecular science, institute for molecular science, myodaiji, okazaki 4448585, japan, and department of nanomaterials. The reduction of graphite oxide by hydrazine was used be. There are several other reports on reduction of graphite oxide by hydrazine hydrate48,5965. The reduction of electrically insulating graphene oxide, which is exfoliated from graphite oxide go. Hydrazine was reacted with small conjugated aromatic compounds containing various oxygen functional groups to mimic the structure of graphene oxide. A lowtemperature method to produce highly reduced graphene oxide. Reduced graphene oxide rgo is the form of go that is processed by. Synthesis, fabrication of graphene oxide membranes, and controlling their diffusion by thermal reduction by abdulrahman alhadhrami a thesis presented to the university of waterloo in fulfillment of the thesis requirement for the degree of doctor of philosophy in chemistry waterloo, ontario, canada, 2016 abdulrahman alhadhrami 2016. No reaction path was found for the hydrazinemediated reductions of the hydroxyl, carbonyl, and carboxyl groups of go. Dec 03, 2015 graphite oxide, graphene oxide and reduced graphene oxide rgo, for some out there who get confused between the three. Solvothermal reduction of graphite oxide using alcohols.
Hydrazine was reacted with small conjugated aromatic compounds containing various oxygen functional groups to mimic the structure of. Synthesis of high quality reduced graphene oxide nanosheets free of paramagnetic metallic. Study of reduced graphene oxide preparation by hummers. Graphene oxide go, product numbers 763705 and 777676 is a unique material that can be viewed as a single monomolecular layer of graphite with various oxygen containing functionalities such as epoxide, carbonyl, carboxyl and hydroxyl groups. Hydrazine was reacted with small conjugated aromatic. The reduction effect and mechanism of the asprepared go reduced with hydrazine hydrate at different temperatures and time were characterized by xray photoelectron spectroscopy xps, fourier transform infrared spectroscopy ftir, elemental analysis ea, xray diffractions xrd, raman spectroscopy.
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