Ftir spectra of iron oxide nanoparticles synthesized via thermal decomposition. Noncolvalent functionalization of graphene with end. The strong peak at corresponds to an interlayer spacing of about 0. Morphological transformation of gold nanoparticles on.
On the other hand, ccg, or partially reduced colloid of graphene oxide, uses the remnant oxygencontaining groups for displaying the stability of mildly oxidised graphene oxide sheets. Graphene oxide flakes with a low oxidation degree and decorated with iron oxide have been obtained in one. Xray diffraction of graphene oxide and reduced graphene oxide synthesized by chemical reduction of exfoliated and intercalated graphite oxide is presented in figure 2. Uvvis absorbance spectra of reduced graphene oxide rgo or graphene uvvis absorbance spectra of reduced graphene oxide rgo or graphene 200 250 300 350 400 450 500 550 5 4 3 2 1 intensity wavelength nm 270nm.
Uv vis absorption spectra of as prepared graphene oxide dispersed in different four solvents by means of bath sonication. Insets of digital images of goqds under excitation of 365 nm. Sandhya murali et al international journal of chemtech research, 2018,1103. The powder was characterized by xray diffraction, scanning electron microscopy, transmission electron microscopy, selectedarea electron diffraction, uvvis optical absorption, and photoluminescence spectroscopy analyses. Ultravioletvisible uvvis spectroscopic data show that fewlayer go dispersions can be distinguished from multi and thicklayer dispersions by a more intense peak at 230 nm. Uvvisible spectra recorded in distilled water at different reaction time. Figure 2a, indicates that go and ngo have an absorption band at. Figure 2 shows the uvvis absorbance spectra of ansg and graphite oxide in water. K2feo4 fevibased compound, obtained from a dry synthesis, has been used as a green oxidant of graphite to produce graphene oxide, avoiding the use of the toxic permanganates. Comparison of the aqueous dispersion of graphite oxide and ansg are shown in the.
Advanced chemical reduction of reduced graphene oxide. Graphene oxide go was reduced by a rapid, effective and ecofriendly electrochemical method of repetitive cathodic cyclic potential cycling, without using any reducing reagents. Zno nanoparticles have been synthesized by precipitation method from zinc nitrate. Xray photoelectron spectra xps show that the change of uvvis absorption intensity of. The first main ingredient for the synthesis of rgozno composite is graphene oxide. Synthesis and characterization of iron oxide nanoparticle. Goqd resulted as a better support than rgoqd because of the presence of higher functional. The optical absorption spectra was recorded by using shimadzupharmaspec17000 uvvis.
The structure of graphene oxide was generally the same as graphene except for some oxygencontaining functional groups, such as epoxy group, hydroxyl and carboxyl 69. For clarity, c 1 s and o 1 s spectra and their fits are shown after shirley background subtraction and vertically offset from the fitting components. The preparation of graphene oxide was controlled by reaction temperature, reaction time and concentration of kmno 4. Xray photoelectron spectra xps show that the change of uvvis absorption intensity of go is caused by a conjugative effect related to chromophore aggregation. Uvvis spectra show that rgo has much higher optical adsorption than go in both the uv and visible ranges, consistent with their colors shown in b. Onepot green synthesis of highly reduced graphene oxide. Uvvis absorbance spectra of reduced graphene oxide rgo. The uvvis absorbance spectrum of zinc oxide nanopartic. But much higher amount of graphene oxide can leads to incomplete reduction and thus bad quality final product. Graphene oxide quantum dots as the support for the.
Uvvis spectrum of graphene oxide raman spectrum of graphene oxide. Graphene and graphite oxide have gained vast popularity and become wonder materials in the present context of research and development. Figure 2 optical properties of nanographene oxide sheets. Synthesis and characterization of graphene thin films by. Ultravioletvisible spectroscopy of graphene oxides aip publishing. Pdf ultravioletvisible spectroscopy of graphene oxides. Surface functional groups of go layers and the oxidative debris od stacked on them were investigated after od was extracted. Uv visible spectrums obtained as a result of laser irradiation and mixing go with ammonia. The znonps were dispersed in ethanol with concentration of 0. Graphene oxide go layers are the individual sheets of conventional graphite oxide cgo synthesized from graphene.
Over the span of years, improvements over various synthesis methods of graphene are constantly pursued to provide safer and more effective alternatives. The prepared graphene oxide and reduced graphene oxide were characterized by uvvisible spectroscopy, ftir spectroscopy, and xrd. Goqd and rgoqd were used as supporting agents for the in situ generation of gold nanoparticles, avoiding the use of additional stabilizers. Uvvis spectroscopy absorbance mode is the most commonly used. Analysis was performed successfully using fourier transform. The fast electronhole recombination in mesoporous carbon nitride mcn photocatalyst has spurred a great interest to improve its efficiency with addition of various modifiers. Nanocomposites a lot of research works have been reported on graphene or rgo andor go.
Having unique properties, graphene layers are a quite interesting nanomaterial for industrial applications. The absorption peak at 292 nm which indicates n transitions of co. The spectra in figures 2a and 2b show two peaks corresponding to graphene oxide and graphene. Preparation of waterdispersible graphene by facile. Pdf comparison on graphite, graphene oxide and reduced. Femtosecond laser interaction with graphene oxide aqueous. In this work, the go nanosheets were prepared by a chemical exfoliation technique. Xray powder diffraction patterns of pristine graphite, graphene oxide before and. The shoulder peak at 302 nm is started diminishing in less than 8 h of exposure to sunlight and completely vanished a er 16 h. Both graphene oxide and reduced graphene oxide were characterized by uvvisible spectroscopy, ftir spectroscopy, and xrd techniques. Graphene oxide quantum dot goqd and reduced good rgoqd were synthetized using a simple and straight methodology based on an oxidative treatment and sonication. Graphene can be obtained in the form of reduced graphite oxide.
Graphene oxide go and reduced graphene oxide rgo are known to have superior properties for various applications. Synthesis, characterization, and spectroscopic properties. Sem images for a asprepared go and b irradiated rgo 10 figure 23. Xrd patterns showed that zno nanoparticles have hexagonal unit cell structure. Dispersions containing fewlayer layers go can be distinguished from those containing multilayer 410 layers and thicklayer 10 layers go by the intense peak in their uvvis spectra at 230 nm. Preparation and characterization of graphene oxide. Facile reduction of graphene oxide suspensions and films. The xrd patterns of graphite oxide in figure 2, showed that a strong diffraction peak at 9.
Graphene oxide was synthesized by a onestep environmentally friendly mechanochemistry process directly from graphite and characterized by raman, ftir and uvvis spectroscopies, atomic force. High yield controlled synthesis of nanographene oxide by. Uv vis spectrum for graphene oxide and graphene uvvis spectra of go figure 2 before and after irradiation at 35 kgy, shows that there are two absorption peak which appears at 292 nm and 237 nm. Ftir spectra observed of zinc oxide nanoparticles in their investigation. The electrochemically reduced graphene oxide ergo was characterized by uvvis, eis and zetapotential measurements. As the colloid is titrated with naohhcl, the ensuing change in. All answers 18 uvvis absorption spectra of graphene oxide should have peak at about 230 nm related to transitions of the aromatic cc bond and a shoulder at about 300 nm correspond to n. Graphene oxide go has recently attracted great attention due to its unique chemical and physical properties.
Doping nanoparticles doping nanoparticles onto graphene or go has been done for the following works brenner, 2012. This article presents the influence of capping ligand and surface interaction types on the coarsening or reshaping behavior of surfaceimmobilized gold nanoparticles with different core size and shape. Synthesis, characterization, chemical reduction and. This work compares the properties of go and rgo with graphite. Graphene oxideiron oxide nanocomposites for water remediation. Synthesis of graphene oxide go by modified hummers. 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. Thermal decomposition and coprecipitation 33 figure 18.
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. Xrdhta, uv visible, ftir and sem interpretation of. The afm images of a graphene oxide and b reduced graphene oxide flake 9 figure 22. Original article the preparation of reduced graphene oxide. Uvvis diffuse reflectance spectroscopy uvvis drs using a uvvis spectrophotometer cary500, varian co. Pure graphite oxide showed a strong absorption peak at 230 nm which shifted to 262 nm in ansg, suggesting the restoration of electronic conjugation within the graphene sheets 9. Controlled synthesis, characterization and reduction of graphene. Research article preparation and characterization of graphene oxide jianguosong, 1 xinzhiwang, 1 andchangtangchang 2 college of environment and materials engineering, yantai university, qingquan road, laishan district, yantai, china. The strong quantum confinement effect as well as abundant edges and oxygen functional groups enable nanographene oxide ngo a variety of intriguing applications such as catalysis, bioimaging, drug delivery and photovoltaic devices. The structural and optical properties of the asprepared go nanosheets were characterized by raman, ftir, uvvis and photoluminescence spectroscopy.
The obtained graphene oxide was reduced to reduced graphene oxide by ascorbic acid. Graphite oxide uvvis spectrum reveals two new absorbance peaks at 312 nm and 361 nm in addition to the graphene oxide and graphene dispersion peaks. Uvvis spectrum of iron oxide nanoparticles synthesized by two methods. Graphene and its oxides have attracted much attention because of their interesting electronic properties. Uvvisible spectroscopy the optical characterization of the sample was recorded on uvvis absorption spectrophotometer figure 4 a shows the uvvisible absorption spectra of zno. Graphene oxide and nanographene oxide optical properties uvvis absorbance spectra and photoluminescence emission were obtained. Ultravioletvisible spectroscopy of graphene oxides. However, the generation of graphene layers from graphite is quite expensive, but can be achieved at lower cost via controlled oxidation of graphite. Dispersions of fewlayer layers, multilayer 410 layers and thicklayer 10 layers graphene oxide go were prepared by a modified hummers method with different mass ratios of kmno4 to graphite. Xrdhta, uv visible, ftir and sem interpretation of reduced.
Green preparation and characterization of graphene oxide. Reduced graphene oxidemesoporous carbon nitride as. Research article preparation and characterization of. Figure 3 shows the uvvis absorption spectra for go, agrgo and agrgoaa composites. In the present study, the mcn was modified by reduced graphene oxide rgo that was synthesized via a novel photocatalytic reduction method with different ratios of go to mcn to produce rgomcn composites. The uv vis spectrum of polystyrene functionalized graphene in tetrahydrofuran shows a strong absorption peak around 275 nm, which is comparable to reduced graphene oxide after the conjugated graphitic structure has been restored by chemical reduction. However, the development of ngo is severely hindered because of the difficulty in controlled mass production. Ultravioletvisible spectra were recorded for aqueous solutions of graphite oxide by using uv1800, shimadzu spectrophotometer.
Controlled synthesis, characterization and reduction of. Graphene oxide quantum dots derived from coal for bioimaging. What is your opinion about this uvvis absorption spectra. Graphene oxide ngo was usually prepared by oxidation of gra phene. Nanographene oxide for cellular imaging and drug delivery. To our knowledge these peaks were not observed before. Uvvis absorption spectra of go aqueous dispersions before 1 and after. A simple ozone bubbling procedure for the preparation of. Graphene oxideiron iiivi oxides nanocomposites have been produced with a fast and onepot synthesis. Research article aqueous colloidal stability of graphene.
Please reduce the thickness of film or dilute the go in case you are using cuvette. The room temperature uvvis absorption spectra of znonps are shown in figure 4. Graphite oxide was synthesized from graphite power spectral pure, sinopharm chemical reagent co. Synthesis, characterization, chemical reduction and biological application of graphene oxide by xiguang gao a thesis presented to the university of waterloo. Characterization of graphene oxide and reduced graphene. Sonochemical preparation of functionalized graphenes. As much concentration we take initially, that much amount rgo we get at the end of the process.
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