Thermogravimetric analysis tga analysis shows the nanocomposites have an enhanced thermal stability over the original components. The change in the weight of the substance is recorded as a function of temperature or time. After being dried at 50 c, the polymeric films were tested using tga. To unveil the mechanisms underlying these contradictions, we performed antibacterial assays under comparable conditions. The number of layers present has been estimated by comparing the area of the d and g peaks to the area of the silicon substrate peak ca 950 cm1. A raman spectrometer nrs3100, jasco with a 532 nm nd. Azobenzene derivatives have fast light response characteristics. Graphene oxides gos with large sheets and more perfect aromatic structure were prepared by a novel modified hummers method.
Thereafter, graphene oxide go was pre pared by the exfoliation of the graphite oxide in distilled water in an ultrasonicator. The crystal structures and surface atomic compositions were analyzed using an x. Potts a, aruna velamakanni a, shanthi murali a, rodney s. Graphene oxide go has been initially prepared by a modified hummersmethod. The high dispersion stability of graphite oxide enables it to form a single graphene oxide layer on any substrate so that it can be applied to numerous devices such as flexible displays, transparent conducting films, and transistors for large area electronics. Tga spectra of graphite, graphene oxide, and graphenea. Thermal degradation of graphene based mineral oil lubricants was studied using thermogravimetric analysis tga. Graphite oxide was synthesized by an improved hummers method. Synthesis of graphene oxide, polydopaminereduced graphene oxide, and reduced graphene oxide. Graphene oxide reinforced polycarbonate nanocomposite films. Promising applications of graphene and graphenebased. Graphite oxide go is an interesting material because of its excellent solubility in water, unlike graphite.
Jul 26, 2007 indeed, as the moisture content of graphene oxide paper decreases with increasing temperature see thermogravimetric analysis curve, supplementary information 6, the modulus increases from 17 to. Due to its unique properties, graphene oxide has become one of the most studied materials of the last decade and a great variety of applications have been reported in areas such as sensors, catalysis and biomedical applications. The oxidation step was performed using h 2 so 4 and kmno 4 graphite. Apr 30, 2020 thermogravimetric investigation of the formation electrochromic layers of nickel oxide this is then heated and held isothermally for a certain time at a particular temperature i. Over the span of years, improvements over various synthesis methods of graphene are constantly pursued to provide safer and more effective alternatives. The thermal reduction process has been analyzed with the help of fourier transform infrared spectroscopy, thermogravimetric analysis, and thermal degradation kinetics. To produce this nanocomposite with go surface, glycine with.
Structural analysis of graphene oxidesilver nanocomposites. Pdf rapid and mild thermal reduction of graphene oxide go to. This comprehensive volume systematically describes the fundamental aspects and applications of graphene oxide. New additions will be communicated via the gographene blog. Thermogravimetric analysis tga of polymers is conducted to measure weight changes as a function of temperature and time. Graphite 1 g, grade 3061, asbury carbon and sodium nitrate 0. In this work, we synthesized graphene oxideglycine gog nanocomposite. Graphene oxide was synthesized by a onestep environmentally friendly mechanochemistry process directly from graphite and characterized by raman, ftir and uvvis spectroscopies, atomic force microscopy, xray diffraction, scanning electron microscopy, energydispersive xray spectroscopy and thermogravimetric analysis. To produce this nanocomposite with go surface, glycine with known concentration was added to go suspension in ethanol solvent. Go was later reduced thermally to obtain reduced graphene oxide rgo. Design and characterization of chitosangraphene oxide.
Tga spectra of graphite, graphene oxide, and graphenea openi. Thermogravimetric analysis curves of graphene oxide, re. Thermogravimetric analysis curves of graphene oxide, re openi. Graphene ag nanocomposites gnsagnps were fabricated via a green and facile method, employing graphite oxide go as a precursor of graphene, agno3 as a precursor of ag nanoparticles, and sodium. Mechanical and thermal properties of graphene oxide. The optical bandgap, as calculated by taucs analysis shows a progression from. Having unique properties, graphene layers are a quite interesting nanomaterial for industrial applications.
We report the modification of graphene oxide go by thermal reduction to obtain reduced graphene oxide rgo and subsequent modification by sulfophenyl groups as well as the characterization of these materials by thermogravimetric analysis coupled with mass spectroscopy tgams. Thermogravimetric analysis advanced techniques for better. Initially graphite oxide was prepared by oxidizing the purified natural flake graphite nfg by the modified hummers method. The other temperatures used in this study were selected from the thermogravimetric analysis tgadtg of the graphite oxide exfoliated by sonication figure 3b. The results showed that the residual gum content of the hemp using go bath is lower. In thermogravimetric analysis, the sample is heated in a given environment air, n2, co2, he, ar, etc. Morphology, crystallinity, and molecular weight of poly.
Fast and fullyscalable synthesis of reduced graphene oxide. This set features volumes 1, 2, 3, 4, 5, 6, 7, and 8 of the handbook of graphene. In this study, we use our recently prepared graphene oxide go with an almost intact 0 framework of catoms aigo to probe the thermal stability of. Graphene oxide was synthesized using hummers method as this method yields more compared to other modified chemical exfoliation techniques. Thermal gravity analysis for the study of stability of graphene oxide. Yag laser was employed for quantifying molecular vibrations. Both composites were carefully investigated by scanning electron microscopy sem, fourier transform infrared spectroscopy ftir, and thermogravimetric analysis tga. Visualization of defect densities in reduced graphene oxide.
The initial discharge and charge capacities of rgbv 2 o 5 composite were 282 and 280 ma h g. Understanding the behaviour of graphene oxide in portland. The temperature is increased at a constant rate for a known initial weight of. The weight changes of polymeric materials can be caused by decomposition and oxidation reactions as well as physical processes such as sublimation, vaporization, and desorption. The gocs nanocomposite was covalently bonded and was characterized by fourier transform infrared spectroscopy ftir, xray photoelectron spectroscopy xps, thermogravimetric analysis tga, scanning electron microscopy sem, atomic force microscopy afm and by dynamic light scattering dls.
Pdf in this study, graphene oxide go was synthesized from graphite. Uniform decoration of vanadium oxide nanocrystals on. Surface functional groups of go layers and the oxidative debris od stacked on them were investigated after od was extracted. One step mechanosynthesis of graphene oxide directly from.
Graphene oxide go powders were prepared through a modified hummers method according to our previous publication. Eds analyzer and thermogravimetricdifferential thermal analysis. Here we report the synthesis and characterization of a novel cathode for magnesium secondary batteries based on graphene oxide go and vanadium v active species. Preparation and characterization of graphene oxide paper nature. Synthesis of polyanilinegraphene oxideazobenzene composite. Superexpansion of assembled reduced graphene oxide. We report on the structural analysis of graphene oxide go by transmission electron microscopy tem. Assynthesized graphene sheets of 8, 12, and 60 nm thick and engine oil formulations 20w50 sncf and 20w50 sjcf were used for synthesizing various test samples.
Microwaveassisted onestep degumming and modification of. The book is designed as an introduction to the topic, so. Pdf preparation of graphene by the rapid and mild thermal. Study of thermal stability by tga showed that thermal stability of go was more than that of the gog nanocomposite. Although graphite oxide is a multilayer system, monolayer flakes and fewlayer flakes can be found in a graphene oxide dispersion. In situ raman spectroscopy study of the formation of. The potential application for this technology was demonstrated by the use of rgotio 2.
An eightvolume set of handbooks on graphene research and applications. Each sample weighting approximately 8 mg was heated from 50 c to 600 c with a rate of 10 cmin under nitrogen. In saline, bare go sheets were intrinsically bactericidal, yielding a bacterial. Depending on the information we require, our analysis approach may be straight forward, however, more complex systems may require more indepth analysis. Preparation of coppercobaltnickel ferritegraphene oxide. Graphene, a monolayer of sp 2bonded carbon atoms has stimulated vast scientific interest due to its unique properties. Thermogravimetric analysis tg was carried out using a mettler toledo tgasdta851. Dynamic mechanical analysis, fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis were employed to study the mechanical properties in varied temperatures to infer the influence of graphene oxide on. Ruoff a, a department of mechanical engineering and the texas materials institute, the university of texas at austin, one university station c2200. Rgotio2, reduced graphene oxide titanium dioxide nanocomposite. Thermogravimetrydifferential scanning calorimetry tgdsc analysis was carried out using a thermal analyser sta6000 from perkinelmer.
Chapter 6 thermogravimetric tg dta analysis of snsefe x. The adsorbent was characterized using fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron. Study of graphene nanolubricant using thermogravimetric. Here we report, a detailed investigation of graphene oxide go, reduced graphene oxide rgo and sulfophenylmodi ed rgo srgo by thermogravimetric analysis coupled with mass spectrometry tgams analysis. In this work, we synthesized graphene oxide glycine gog nanocomposite. Analysis was performed successfully using fourier transform. Elucidating the chemistry behind the reduction of graphene. Synergistic effect composed of graphene oxide go and halloysite hnt to serve as a promising anticorrosion performance and to enhance flame retardant fr properties of epoxy nanocomposite coating nc is studied. Mechanical properties of the composite were tested. In this study, we have fabricated antibacterial, lightweight, transparent, and flexible graphene oxide go reinforced polycarbonate thin films by a facile and lowcost methodology. All these advantages make the reduced graphene oxide nanocrystalline. Pdf preparation and characterization of graphene oxide paper.
Preparation and characterization of graphene oxide paper. May 30, 2015 in this work, we synthesized graphene oxideglycine gog nanocomposite. Noncolvalent functionalization of graphene with end. We demonstrated that the graphite did not need to be oxidized to such a deep degree as described in hummers method because the space distance increased little when the oxidation proceeded to a certain extent and the obtained graphite oxides gtos could. Study of graphene nanolubricant using thermogravimetric analysis. Graphene oxide is a distorted graphene monolayer in which a fraction of carbon atoms have been oxidised into various functional groups, such as carbonyl and carboxyl. Thermogravimetric analysis tga, tg209 f3 was performed at a heating rate of 10 c min1 in air.
Due to the presence of oxygen functionalities, graphene oxide can easily disperse in. Thermogravimetric analysis tga, differential scanning calorimetry dsc, and mass spectroscopy were used complementary to raman spectroscopy to assist with the interpretation of the obtained data. Sulfurdoped alkylated graphene oxide as highperformance. Furthermore, graphene reduced graphene oxide rgo can be produced at a lower cost through largescale chemical synthesis 24,25.
However, the generation of graphene layers from graphite is quite expensive, but can be achieved at lower cost via controlled oxidation of graphite. Graphene oxide go layers are the individual sheets of conventional graphite oxide cgo synthesized from graphene. Thermogravimetric analysis tga of graphite, graphene oxide and reduced graphene was carried out under n2 flow using ta instrument thermogravimetric analyzer q50 usa and their masses were recorded as a function of temperature. Synthesis of reduced graphene oxide with adjustable. Electron diffraction shows that on average the underlying carbon lattice maintains the order and latticespacings of graphene. The incorporation of carbonaceous nanofillers into polymers can result in significant materials with improved physicochemical properties and novel composite functionalities. Raman spectroscopy is a powerful characterization tool for the analysis of carbon nanomaterials, such as graphene. 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.
Thermogravimetric analysis curves of graphene oxide, reduced graphene oxide, titanium dioxide, and reduced graphene oxide titanium dioxide nanocomposites. In this article, samples of phenolic resin reinforced with graphene oxide were prepared. Thermogravimetric analysis, structural and vibrational analyses, and highresolution. Spectroscopic analysis shows that the functional groups and oxygen.
Investigation of the thermal stability of the carbon. The weight changes of polymeric materials can be caused by decomposition. Vacuum filtration of colloidal dispersions of graphene oxide sheets through an anodisc membrane filter yielded, after drying, freestanding graphene oxide paper with thicknesses ranging from 1 to 30mm supplementary information 1. Though the extraction of graphene through hummers method is one of the oldest techniques yet it is one of the most suitable methods for the formation of bulk graphene. The interfacial heat transfer efficiency of graphene oxide. The purpose of this work is the structural analysis of graphene oxide go and by means of a new structural model to answer the questions arising from the lerfklinowski and the lee structural models.
However, very little is known regarding the chemically induced reduction method of graphene oxide go in both solution. Biofabrication of lysinibacillus sphaericusreduced graphene oxide in threedimensional polyacrylamidecarbon nanocomposite. Facile, mild and fast thermaldecomposition reduction of graphene. Graphene oxide has the potential to enhance the low tensile strength of portland cement matrices, but research is required to understand how it behaves in blends with cement and. Request pdf structural analysis of graphene oxide silver nanocomposites. Jun 28, 2019 a series of nanocomposites were prepared, incorporating different graphene oxide filler contents 0. Graphite oxide was synthesized from graphite power spectral pure, sinopharm chemical reagent co. The samples were heated from room temperature to 600 c at 5 cmin. Fabrication of a phosphorylated graphene oxidechitosan.
Microwaveassisted onestep degumming and modification of hemp fiber with graphene oxide go have been studied. Enhancement of the strength of biocomposite films via. Subsequently reduced graphene oxide rgo having few layer graphene is extracted from go by the thermal reduction of go. Request pdf structural analysis of graphene oxidesilver nanocomposites. The crosslinking of go with cs and the subsequent phosphorylation of the gocs composite were demonstrated by scanning electron microscopy sem, powder xray diffraction. Indeed, as the moisture content of graphene oxide paper decreases with increasing temperature see thermogravimetric analysis curve, supplementary information 6, the modulus increases from 17 to. Thermogravimetric analysis is a useful tool in our laboratory toolbox to look at the decomposition, sorption, desorption characteristics of our materials. Thermogravimetric analysis tga was employed to investigate the thermal stability of these nanocomposites. Availability of the basal planes of graphene oxide. Preparation and characterization of graphene oxidepmma. Results of characterization by sem and ftir showed that nanocomposite was created by the reaction between go and g. Preparation and characterization of fe3o4gallic acid. Thermogravimetric analysis has also been performed.
Graphene oxide go was prepared by oxidizing natural graphite powder sp, 320 mesh based on a modified hummers method as originally presented by kovtyukhova and colleagues. Herein, a new synthesis strategy was developed to synthesize a novel phosphorylated graphene oxide gochitosan cs composite denoted as gocsp for uvi removal. Go was reported to be bactericidal in saline, whereas its activity in nutrient broth was controversial. These results also reveal that single go sheets are highly electron. The tgams data con rmed the covalent gra ing of sulfophenyl groups on rgo. Thermal gravity analysis for the study of stability of. Mar 24, 2017 in this study, graphite oxide go is synthesized from natural graphite flakes by the modified hummers method. Aug 18, 2019 graphene oxide is an excellent material to solve this problem 4,5,6. Reduced graphene oxides rgos have attracted considerable interest, given their potential applications in electronic and optoelectronic devices and circuits. Synthesis of graphene oxide go by modified hummers. Hydrazinereduction of graphite and graphene oxide sungjin park a,b, jinho an a, jeffrey r.
Reduced graphene oxide improves moisture and thermal. The graphene content of the rgbv 2 o 5 composite, measured by thermogravimetric analysis, was approximately 5 wt %. The thermogravimetric analysis tga is applied to determine the alkylation efficiency of the reactions between the butylamine goc4, octylamine goc8, laurylamine goc12, octadecylamine goc18, and the sulfurdoped graphene oxide the oxidation time of the graphene oxide is. There are significant controversies on the antibacterial properties of graphene oxide go. Nano express open access highquality reduced graphene oxide. Adsorption of basic magenta on graphene oxide modified sugarcane bagasse renjin gao,a,b xiaoting shen,a a,b,cand liwei wang, a novel adsorbent was prepared using sugarcane bagasse modified with graphene oxide. Synthesis and characterization of sulfophenylfunctionalized. The prepared zngraphene oxide zngo and cugraphene oxide cugo fertilizers showed a biphasic dissolution behavior compared to that of commercial zinc sulfate and copper sulfate fertilizer granules, displaying desirable fast and slow micronutrient release. Using an epoxy as the matrix, goepoxy, hntepoxy, and hybrid gohntepoxy samples are prepared and the performance is characterized.
Adsorption of basic magenta on graphene oxide modified. Graphene oxide reinforced polycarbonate nanocomposite. Chrysalislike graphene oxide decorated vanadiumbased. Dec 20, 20 here we reported a novel route to synthesize a hierarchical nanocomposite panifrgo of polyaniline pani nanowire arrays covalently bonded on reduced graphene oxide rgo. 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. The thermal stability of coppercobaltnickel ferrite, graphene oxide, polyaniline and copper cobalt nickel ferritegraphene oxidepolyaniline composites at 0. The effect of vacancy defect on the thermal conductance of the interface is considered. Raman spectroscopy has shown that william blythes graphene oxide is fully oxidised with an idig ratio of about 1, which is fairly typical for graphene oxide. Article reduced graphene oxide improves moisture and thermal stability of perovskite solar cells huiseon kim,1,56 bowen yang,2 minas m.