This paper focuses on using a simplified approach for the reduction of graphene oxide to graphene sheet doped nitrogen. The use of the vapour phase is needed to pattern hydrophilic gos on prepatterned substrates, as well as in in situ reduction to hydrophobic reduced graphene oxides rgos. Jan 24, 2012 chemically modified graphene platelets, produced via graphene oxide, show great promise in a variety of applications due to their electrical, thermal, barrier and mechanical properties. Reduced graphene oxide and its natural counterpart shungite carbon elena f. Graphite oxide, graphene, hyrazine hydrate, sodium borohydride, sodium nitrite, graphene sheets introduction graphene is the first stable twodimensional crystal 1, discovered in 2004. Preparation method n 2h 2 chemical reduced method 2.
Robinson, hernan sanchez, georgi diankov, hongjie dai department of chemistry, stanford university, stanford, california 94305 email. Reduced graphene oxide by chemical graphitization article pdf available in nature communications 16. A new approach to make graphitic thin films from graphene oxide go is presented. Graphene oxide go with various degrees of oxidation was synthesized using a modified hummers method. The reduction of graphene oxide can be achieved a number of ways through thermal, chemical, or electrochemical methods. While the oxygen groups can be partially eliminated by reduction, the damages in the carbon networks remain with the presence of structural defects 26. It can be produced by micromechanical exfoliation of highly ordered pyrolytic graphite, epitaxial growth, chemical vapor deposition, and the reduction of graphene oxide go.
Here, we demonstrate that the highly defective structure of reduced graphene oxide sheets assembled into freestanding, paperlike films can be fully. Processable, singlelayered graphene oxide go is an intriguing nanomaterial with tremendous potential for electronic applications. The anode is fabricated by anchoring sb 2 o 3 onto reduced graphene oxide sb 2 o 3. The suppression of graphitization in ethanol environments is probably caused by the simultaneous supply of carbon and etching species during the. The reaction mechanism is, however, still not well understood, hindering progress in the use of go. Ep3085666a4 method for repairing reduced graphene oxide. The electrical properties of graphene materials with intermediate co have been studied both by reducing individual sheets of graphene oxide on substrates and by oxidizing pristine graphene. Graphene has attracted great interest for its excellent mechanical, electrical, thermal and optical properties. Among them, the chemical reduction of go into reduced graphene oxide rgo has been the most.
Simultaneous nitrogendoping and reduction of graphene oxide. Graphene has various applications, however water soluble graphene could be better option for biomedical applications. Thermal and chemical reduction of graphene oxide sheets which were deposited on a substrate prior to reduction resulted in the onset of electrical conductiv. Mechanical pressing of the graphitized films increased density but decreased crystallinity.
Currently, a number of techniques are used to produce graphene and these include epitaxial growth, chemical vapour deposition cvd, and thermal or mechanical exfoliation. Graphene oxide and its role in eor application production of graphene oxide go via oxidization of graphite with strong oxidizing agents a combination of kmno 4, kclo 4, nano 3 and h 2so 4 has been known as hummers method since 1956 but was then forgotten for a long time. It can be expected that the c contents of the reduced graphene oxide in the composites increased due to reduction treatment of partial oxygen containing functional groups. Graphite oxide, 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. Currently, an improved method for the preparation of graphene oxide was the most common one.
Chemical oxidation of graphite to graphene oxide followed by the reduction process is the commonly used method for mass scale production of graphene or reduced graphene oxide rgo. Structural evolution during the reduction of chemically. Ion storage enhancement in sb2o3reduced graphene oxide. Reduced graphene oxide by chemical graphitization j. Efficient exfoliation of graphite in solutions to obtain highquality graphene flakes is desirable for printable electronics, catalysis, energy storage, and composites. However, very little is known regarding the chemically induced reduction method of graphene oxide go in. The methods which are capable of producing the highest quality graphene tend to be more complex. Natural flake graphite nfg was procured from loba chemie india having a mean size of 60 mesh and purity of 98%. Parameters such as reaction time, reaction temperature, and amount of concentration were varied to study the degree of oxidation of graphite to graphene oxide.
By incorporating smalldiameter, reduced go platelets with go, graphitized films show improved density and crystalline order when compared with pure go. Nucleation ability of thermally reduced graphene oxide for polylactide. Hbv is bloodborne and transfusiontransmitted human pathogen that has a large impact on. The complete restoration of a perfect carbon lattice has been a central issue in the research on graphene derived from graphite oxide since this preparation route was first proposed several years ago, but such a goal has so far remained elusive. Preparation and characterization of nitrogen doped reduced. H ahmad 1,2,3, m tajdidzadeh 1, k thambiratnam 1 and m yasin 2. Subsequently reduced graphene oxide rgo having few layer graphene is extracted from go by the thermal reduction of go.
However, very little is known regarding the chemically induced reduction method of graphene oxide go in both solution and gas phases, with the exception of the hydrazinereducing agent, even though it is essential to use the. Infrared photodetectors based on reduced graphene oxide. Applications of graphene oxide and reduced graphene oxide. The uniquely large and atomically flat surface of graphene and go provides a platform upon which to anchor various chemical species. A comparative study on gassensing behavior of reduced. Chemical analysis of graphene oxide films afterheat and chemical treatments by xray photoelectron and microraman spectroscopy.
The mechanism is mainly the generation of oxygencontaining groups on graphene sheets. Preparation of graphene from chemical reduction of graphene oxide go is recognized as one of the most promising methods for largescale and lowcost production of graphenebased materials. Highquality graphene via microwave reduction of solution. The flow chart for synthesis of go is given in figure 3. Pyrrolidine fullerene graphene oxide graphene c 60 ho o ho ho o ho h 3 co 2 o co 2 ch 3 n be removed from aqueous solutions by gr fig. The effect of degree of reduction on the electrical. Fast and facile preparation of graphene oxide and reduced. Synthesis of graphene oxide and reduced graphene oxide page 70 to exfoliate the layers figure 3. Finally, more effective reduction treatments to improve the reduction of graphene oxide are proposed. Graphitization of graphene oxide with ethanol during. T he chemical derivation of graphene oxide go provides a high yield of covalently functionalized, atomically thin carbon sheets1,2. Large variety of structure and chemical composition of reduced graphene oxide rgo is explained from a quantum chemical standpoint.
Leereduced graphene oxide by chemical graphitization. Graphitization of graphene oxide films under pressure. Synthesis of reduced graphene oxide rgo via chemical reduction alpana thakur, sunil kumar, and v. Synthesized products were then obtained in the form of thin films. Moon i k, lee j, ruoff r s and lee h 2010 reduced graphene oxide by chemical graphitization nat. Synthesis of graphene oxide go by modified hummers. Abstract reduced graphene oxides rgos have attracted considerable interest, given their potential applications in electronic and optoelectronic devices and circuits.
Evaluation of solutionprocessed reduced graphene oxide. An antisolvent for graphene oxide go, hexane, is introduced to increase the surface area and the pore volume of the nonstacked go reduced go 3d structure and allows the formation of a highly crumpled nonstacked go powder, which clearly shows ideal supercapacitor behavior. Potts a, aruna velamakanni a, shanthi murali a, rodney s. Green preparation of reduced graphene oxide for sensing. 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 impact of graphene oxide particles on viscosity.
Reduced graphene oxides rgos have attracted considerable interest, given their potential applications in electronic and optoelectronic devices and circuits. Chemical reduction of graphene oxide rgo was thought to be a promising approach, as graphene oxide go can be easily exfoliated through sonication in liquid phase,15, 16 and chemical. Among all studies on the chemistry of go, the largest portion focused on the reduction of go back to graphene, mainly due to its high relevance to graphene and the gold rush of graphene research over the last decade. The formation of different types of oxygen containing functional groups in go, and their influences on its structure were analyzed using xray diffraction xrd, fourier transform infrared spectra, xray photoelectron spectra xps, zeta potential analysis and raman spectroscopy. A subsequent hightemperature heat treatment improved atomic. Graphene oxide, highly reduced graphene oxide, and. Pdf reduced graphene oxides rgos have attracted considerable interest, given their potential applications in electronic and optoelectronic devices. Tuning the nonlinear optical absorption of reduced. Xps, ftir, raman and electrical conductivity analysis showed that all reductants except dglc without the addition of ammonia were effective to convert go into rgo. By combining density functional theory dft, ab initio molecular. The excellent mechanical and electronic properties of the resulting materials are highlighted with a forward outlook on their applications. The maximally oxidized bulk product is a yellow solid with c. Graphene, single layer graphene, single layer graphene oxide, few layer graphene, few layer graphene oxide, slg, slgo, flg, flgo cas number. Anomalous restoration of graphitic layers from graphene.
Preparation of graphene nanolayer by chemical graphitization of. Graphene oxide is a form of graphene that includes oxygen. Graphite oxide itself is an insulator, almost a semiconductor, with differential conductivity between 1 and 5. 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. Xray diffraction of graphene oxide and reduced graphene oxide synthesized by chemical reduction of exfoliated and intercalated graphite oxide is presented in figure 2. The c contents of the graphene oxide and reduced graphene oxide are 53. The spectra in figures 2a and 2b show two peaks corresponding to graphene oxide and graphene. Chemical structures of hydrazinetreated graphene oxide and.
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. Reduced graphene oxide by chemical graphitization nasaads. A simple method for the reduction of graphene oxide by sodium. Simultaneous nitrogendoping and reduction of graphene oxide xiaolin li, hailiang wang, joshua t. Hydrazinereduction of graphite and graphene oxide sungjin park a,b, jinho an a, jeffrey r. Reduction agent temperature c during reduction reduction time h electrical conductivity sm. Impermeable barrier films and protective coatings based on. Synthesis, properties, and applications of graphene oxidereduced. Rgo and it exhibits better electrochemical performance using an ether. As an atypical reductant, ethanol has recently been considered for reducing the oxygen concentration and restoring the graphitic structure in multilayered graphene oxide go during annealing su et al. 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.
However, very little is known regarding the chemically induced reduction method of graphene oxi. Preparation and characterization of graphene oxide reduced. Scientists are always looking for ways to increase the capacity and efficiency of energy storage, and advances in the processes to make graphene oxide have aided in this search. Normal care should be taken to avoid dust explosion risk through high concentrations of dust or finely suspended airborne particles. Nair1 1school of physics and astronomy, university of manchester, manchester m 9pl, uk 2school of earth, atmospheric and environmental sciences, university of manchester, manchester m 9pl, uk. Reduced graphene oxide and its natural counterpart.
Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed. Sep 21, 2010 reduced graphene oxide by chemical graphitization. Go powder thus obtained was dried at room temperature. Synthesis, characterization, structural, optical properties and catalytic activity of reduced graphene oxide copper nanocomposites. Reduced graphene oxide by chemical graphitization at room.
Chemical functionalization of graphene and graphene oxide a. Synthesis of graphene oxide go by modified hummers method. Ruoff, and hyoyoung lee reduced graphene oxide by chemical graphitization, nature communications. Synthesis and characterization of graphene thin films by. References electronic supplementary material esi for chemical communications.
Sigmaaldrich offers a number of reduced graphene oxide products. Water soluble graphene synthesis chemical science transactions. The chemical and structural analysis of graphene oxide with. The oxidation of graphite in protonated solvents leads to graphite oxide, which. Among the large number of chemical reducing agents used to prepare rgo or graphene, the most efficient reductant is hydrazine. Chemical graphitization from graphene oxide go to graphene has been introduced for mass production.
Graphene oxide sheets chemically crosslinked by polyallylamine. The unique structural features, such as large and planar sp2 hybridized carbon domain. Some reported examples of graphene oxide reduction include. However, being hydrophilic, graphite oxide disperses readily in water, breaking up into macroscopic flakes, mostly one layer thick. However, very little is known regarding the chemically induced reduction method of graphene oxide go in both solution and gas phases, with. The effect of surfactants and their concentrations on the. This study reports a new, green, and efficient reducing agent caffeic acidca for go reduction. Lightweight, flexible graphite foils that are chemically inert, hightemperature resistant, and highly electrically and thermally conductive can be used as component materials in numerous applications.
We report a new approach to making highly dense, oriented, and crystalline graphite films from heattreated and pressed graphene oxide go. Dec 14, 2015 the process involved preparation of graphene oxide and its chemical reduction with different reductants to obtain reduced graphene oxide. The calculations are supported by infrared and xray photoelectron spectroscopy measurements. 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 electronics, graphene oxide can be used in light emitting diodes leds and solar cell devices. Large scale production of graphene can also be effectively realized through chemical reduction of graphene oxide. Apr 21, 2014 excellence in research 2011 prepared on july 2012. Sigmaaldrich offers a number of graphene oxide products. The objective of this work is to investigate the feasibility of using ammonia as the. Pdf reduced graphene oxide by chemical graphitization. In this work, we presented a novel route to synthesize boron doped reduced graphene oxide rgo by using the dielectric barrier discharge dbd plasma technology under ambient conditions. The structure and properties of go are much dependent on the particular synthesis method and degree of oxidation. Membranes made from graphene and its chemical derivative called graphene oxide 1,2,3 go show a range of unique barrier properties 4,5,6,7,8. Plasmainduced highly efficient synthesis of boron doped.
Chemical reduction of graphene oxide using green reductants. Finally, the exfoliated go graphene oxide was reduced to graphene by the. Preparation of graphene nanolayer by chemical graphitization of graphite oxide. Fabrication and characteristics of reduced graphene oxide. Redfern,4 and guozhen yang1,3 1beijing national laboratory for condensed matter physics, in stitute of physics, chinese academy of sciences, po box 603, beijing 100190, china 2department of micro and nanosciences, aalto. Graphene oxide vs graphene property go rgo graphene composition c 2 o c 5 o c 100 o c sheet thickness 1 nm 0.
Since graphene was first reported in 2004, made using. Tuning the nonlinear optical absorption of reduced graphene oxide by chemical reduction hongfei shi, 1 can wang,1, zhipei sun,2 yueliang zhou, kuijuan jin,1,3,5 simon a. Graphite oxide with large lateral dimensions has an exfoliation yield of 100%, but it has not been possible to completely remove the oxygen functional groups so that the reduced form of graphene oxide go. Antisolvent derived nonstacked reduced graphene oxide for. Pdf synthesis, characterization, structural, optical. We spincoated go thinfilms on quartz and characterized their sheet resistance and optical transparency using different reduction treatments.
Buy graphene oxide graphene oxide products acs material. Synthesis and characterization of reduced graphene oxide. Reduced graphene oxide by chemical graphitization nature. Doctoral thesis, nanyang technological university, singapore. Towards full repair of defects in reduced graphene oxide. Graphene oxide go has been initially prepared by a modified hummersmethod. This paper presents a comparative study on gassensing behavior of reduced graphene oxide rgo synthesized by chemical and green synthesis route. Solventfree mechanochemical reduction of graphene oxide into. Graphenic foils can be prepared by thermally transforming graphene oxide films. Graphene oxide film as a template for the creation of threedimensional lamellar metal oxides and reduced graphene oxide metal oxide hybrids volume 4 issue 4 xiguang gao, mahyar mazloumi, louis cheung, xiaowu shirley tang. Graphene oxide products sort by featured best selling alphabetically, az alphabetically, za price, low to high price, high to low date, new to old date, old to new grid view list view.
Read thiol functionalized reduced graphene oxide as a base material for novel graphene nanoparticle hybrid composites, chemical engineering journal on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Reduce graphene oxide has suitable functional groups such as carboxyl, epoxyl and hydroxyl, go produced by vigorous oxidation of graphite by hummers method, is an ideal nanocarrier for efficient drug and gene delivery. Infrared photodetectors based on reduced graphene oxide nanoparticles and graphene oxide. In this chapter, we discuss a variety of chemical reactions introduced for go. Reduced graphene oxide by chemical graphitization mendeley. To restore the graphene lattice, graphene oxide is reduced through thermal annealing or chemical treatment to form reduced graphene oxides 24, 25. A thermal graphitization procedure was most effective, producing films with sheet resistances as low as 102. Recent advances in chemical modifications of graphene. Highly ordered and dense thermally conductive graphitic.
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