Graphene oxide go and reduced graphene oxide rgo are known to have superior properties for various applications. The absorption peak at 292 nm which indicates n transitions of co. Graphene oxide go was reduced by a rapid, effective and ecofriendly electrochemical method of repetitive cathodic cyclic potential cycling, without using any reducing reagents. The functionalization of graphene oxide go with diazonium salt diazoniumgo was conducted for enhancing the dispersibility of go in distilled water. It means existence of a competition between nanofiller and photoinitiator in absorbing uv which results in a less effective curing process. Ultrasensitive selfpowered large area planar gan uvphotodetector using reduced graphene oxide electrodes nisha prakash 1,2, manjri singh 1,2, gaurav kumar 1, arun barvat 1,2, kritika anand 1,2, prabir pal 1,2, surinder p. Extraordinary enhancement of uv absorption in tio2. Controlled synthesis, characterization and reduction of graphene. Despite the fact that there have been many studies of graphite exfoliation, none really addresses the issue of starting form of graphite. Nirvisuv lightresponsive actuator films of polymer. The uv vis spectrum of graphene oxide is also shown in figure 2. Uvvisible spectrometers can be used to measure the absorbance of ultra violet or visible light by a sample, either at a single wavelength or perform a scan over a range in the spectrum. Uvassisted photocatalytic synthesis of tio2reduced.
Development of tio2reduced graphene oxide nanocomposites and. Pegylated nanographene oxide as a nanocarrier for delivering. Sensing formaldehyde using graphene oxide as sensing material. Ultrasensitive selfpowered large area planar gan uv.
Pdf an optical absorbance study using ultravioletvisible uvvis spectrophotometer device has been conducted on graphene oxide go in. Uv vis absorbance spectra of reduced graphene oxide rgo or graphene uv vis 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. To take full advantage of sunlight for photomechanical materials, nirvisuv lightresponsive actuator films of polymerdispersed liquid crystal pdlcgraphene oxide go nanocomposites were fabricated. Graphene is a twodimensional nanomaterial which is composed of monolayers of sp2bounded carbon atoms. Titanium dioxide nanoparticles tio 2 nps graphene oxide go composite layers were deposited by spincoated method the photocatalytic decomposition of both organic dye solutions and domestic wastewater was investigated under simulated sun uv vis light irradiation. Graphene oxide go layers are the individual sheets of conventional graphite oxide cgo. Uv vis spectrum for graphene oxide and graphene uv vis 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. Graphene circuit etching by graphene oxide reduction with.
Uvvis absorbance spectra of reduced graphene oxide rgo. Enhanced uv vis photodegradation of nanocomposite reduced graphene oxideferrite nanofiber films prepared by laserassisted evaporation by albert queralto 1, eniko gyorgy 2, raluca ivan 3, angel perez del pino 2, robert frohnhoven 1 and sanjay mathur 1. Graphene oxide go is often quantified via its uv absorption, typically at around 230 nm. All measurements were made at room temperature with. The reduced material was characterized by xray diffraction xrd, attenuated total reflectance atr ftir, ultraviolet visible uv vis, atomic force microscopy afm and raman spectroscopy which confirm the oxidation of graphite and reduction of graphene oxide into graphene sheet. A mixture of graphene oxide go and tio 2 nanocomposites was reduced photocatalytically by uvirradiation and applied as interfacial layer between a fluorine doped tin oxide fto layer and a nanocrystalline tio 2 film. The uvvisible absorbance spectral analysis was performed using a varian cary 50 uv vis spectrophotometer. Chemically bonded tio2 npgnd composites exhibit highly tunable uv absorption, achieving over 243% enhancement of molar extinction coefficient at 336 nm. A novel highperformance selfpowered uv vis nir photodetector based on a cds nanorod arrayreduced graphene oxide film heterojunction and its piezophototronic regulation xiangxiang yu, a hong yin, a haixia li, a han zhao, a chong li a and mingqiang zhu a. Sensing formaldehyde using graphene oxide as sensing. Pdf comparison on graphite, graphene oxide and reduced.
Synthesis of graphene oxide go figure 1 shows the synthesizing process of graphene oxide go from the graphite powder by using a modified hummers method 12. The prepared samples were characterized by scanning electron. Titanium dioxide nanoparticles tio 2 nps graphene oxide go composite layers were deposited by spincoated method the photocatalytic decomposition of both organic dye solutions and domestic wastewater was investigated under simulated sun uv vis. Preparation and characterization of graphene oxide. This work compares the properties of go and rgo with graphite. Silver nanoparticles graphene oxide nanocomposite for. Kottegoda 1 1 materials technology section of industrial technology institute, no. Sep 20, 2018 the lowtemperature 80 c heating of the go aqueous suspension in the presence of the quartz wafer does not result in the deoxygenation of graphene oxide, as shown by uv vis, ftir and xps. Reference titania sample tio2c was prepared by the same method without graphene addition. Data are presented on the absorbance of small hydrodynamic diameter 1. On the other hand, exfoliated graphene oxide go is the ideal alternative for the production of solution processable graphene, as it can be synthesized in large quantities from inexpensive. 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 department of environmental engineering, ilan university, no.
Xray diffraction analysis of graphite, graphite oxide, and the reduced graphene oxide was carried out using rigaku ultima iv xray diffractometer with cu ka 1 radiation. To investigate the preparation of reduced graphene oxide reducedngo and its photothermal therapy of gliomas in vivo and in vitro. Morphological transformation of gold nanoparticles on. Transparent and conductive graphene oxide polyethylenglycol diacrylate coatings obtained by photopolymerization m. The graphenetio 2 interfacial layer effectively reduced the contact between i 3. Uv vis measurement was performed for the unmodified znonps and go. Xray powder diffraction patterns of pristine graphite, graphene oxide before and. The technique can be used both quantitatively and qualitatively. Uvassisted reduction of graphite oxide to graphene by.
Introduction to ultraviolet visible spectroscopy uv. However, applying graphene to electronic devices via a facile method has proven to be difficult. Ultravioletvisible uv vis spectroscopic data show that fewlayer go dispersions can be distinguished from multi and thicklayer dispersions by a more intense peak at 230 nm. Ultravioletvisible spectroscopy of graphene oxides. Graphene and graphene oxide for biosensing springerlink. Xrdhta, uv visible, ftir and sem interpretation of reduced graphene oxide synthesized from high purity vein graphite c. Controlled synthesis, characterization and reduction of. Here, we have fabricated graphene by reducing graphene oxide go under a 395 nm ultraviolet uv.
Laser synthesis was used for onestep synthesis of titaniagraphene composites gtio2 c from a suspension of 0. Graphite oxide uv vis spectrum reveals two new absorbance peaks at 312 nm and 361 nm in addition to the graphene oxide and graphene dispersion peaks. Uv vis diffuse reflectance spectroscopy uv vis drs using a uv vis spectrophotometer cary500, varian co. Similar activities of both samples for other reactions, i. Ultravioletvisible spectra were recorded for aqueous solutions of graphite oxide by using uv1800, shimadzu spectrophotometer. Graphene oxide uses from supercapacitors, making functionalized graphene, and for a concrete strengthener. 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 strategy is based on phase transition of lcs from nematic to isotropic phase induced by combination of photochemical and photothermal processes in the pdlcgo nanocomposites. Xray photoelectron spectra xps show that the change of uvvis absorption intensity of go is caused by a conjugative effect related to chromophore aggregation. Xrdhta, uv visible, ftir and sem interpretation of. In the present article, the synthesis of tio 2 diazoniumgraphene oxide and its photocatalytic activity for methylene blue mb degradation have been demonstrated. Preparation of thiolfunctionalized graphene oxide tgo thiolfunctionalized graphene oxide was made by following the published procedure 22, 30, 32. The strategy is based on phase transition of lcs from nematic to isotropic phase induced by combination of photochemical and photothermal processes in the pdlcgo. Gnps and all graphitic nanocarbons, absorb light in uv region 98. Typical zno uv vis spectrum revealed two absorption bands centered near the wavelengths of 265 nm and 375 nm.
The structural and optical properties of the asprepared go nanosheets were characterized by raman, ftir, uv vis and photoluminescence spectroscopy. Herein, we report an extraordinary enhancement of uv absorption in tio2 nanoparticles nps incorporated with graphene nanodots gnds of low oxygen concentration. Original article the preparation of reduced graphene oxide. Nir vis uv lightresponsive actuator films of polymer. Ftir spectra of the graphene oxide revealed these oh and cooh functional groups were formed on the graphene surface. Synthesis and characterization of graphene oxide and.
Oct, 2015 similar in structure to the pristine graphene, reduced graphene oxide rgo is derived from graphite powder. Materials free fulltext carbongraphenemodified titania. Doping nanoparticles doping nanoparticles onto graphene or go has been done for the following works brenner, 2012. To take full advantage of sunlight for photomechanical materials, nirvisuv lightresponsive actuator films of polymerdispersed liquid crystal pdlc graphene oxide go nanocomposites were fabricated. Study of ultravioletvisible light absorbance of exfoliated. The prepared graphene oxide and reduced graphene oxide were characterized by uvvisible spectroscopy, ftir spectroscopy, and xrd. Scalable production of reduced graphene oxide rgo from. New sustainable approach for the production of fe3o4.
Uv vis spectroscopy was performed on a shimadzu uv2401pc uv vis spectrometer. Synthesis of reduced graphene oxidetitanium rgotio2. In different graphite forms two major absorbance peaks are. Fabbri3 1 politecnico di torino, dipartimento di scienza dei materiali e ingegneria chimica, corso duca degli abruzzi 24, 10129 torino, italy. However, the generation of graphene layers from graphite is quite expensive, but can be achieved at lower cost via controlled oxidation of graphite. To address this issue various graphite forms solid, powder and sooth and graphite oxide powder are exfoliated in acetonitrile and studied via ultravioletvisible uv vis spectroscopy. Uvvis absorption spectra of go aqueous dispersions before 1 and after. The morphological transformation of gold nanoparticles and nanorods on graphene oxide upon heating at temperatures ranging from 50 to 200 c was investigated.
In this study, the nanocomposite of silver nanoparticles and graphene oxide were produced via insitu synthesis and with the addition of chitosan to investigate the formation of silver nanoparticles on the graphene oxide sheets. Graphene oxide was synthesized by a onestep environmentally friendly mechanochemistry process directly from graphite and characterized by raman, ftir and uv vis spectroscopies, atomic force. Graphite powder were added into concentrated h 2 so 4, p 2 o 5 and k 2 s 2 o 8 then undergo the mixture, filter and wash process and dried overnight. Paper open access related content a prototype ultraviolet.
Hydrazine hydrate reduction method was used to reduce graphene oxide ngo. Ultravioletvisible spectroscopy of graphene oxides aip publishing. Nanocomposites a lot of research works have been reported on graphene or rgo andor go. The aggregation and coarsening behaviors of spherical nanoparticles on graphene oxide were slightly affected by the core size of nanoparticles 1, 3, and 10 nm. At the same time, the exfoliated graphene exhibits very low solubility in common organic solvents 7, due to the essential addition of a stabilizer as the exfoliation liquid medium 8.
Ultraviolet visible uv vis spectroscopic data show that fewlayer go dispersions can be distinguished from multi and thicklayer dispersions by a more intense peak at 230 nm. Conversely, the transparent graphene oxide exhibits a. The uv absorption of graphene oxide is sizedependent. Crystals free fulltext enhanced uvvis photodegradation. Uvreduction of graphene oxide and its application as an. Xrdhta, uv visible, ftir and sem interpretation of reduced. Graphene oxide go is often quantified via its uv absorption, typically at. Various formulations of a novel gold graphene oxide iron oxide augofe3o4 hybrid nanoparticle system were created and subjected to uv vis spectroscopy to determine optimal.
Uv lightresponsive actuator films of polymerdispersed liquid crystalgraphene oxide nanocomposites zhangxiang cheng, tianjie wang, xiao li, yihe zhang, and haifeng yu, beijing key laboratory of materials utilization of nonmetallic minerals and solid waste, national laboratory of mineral materials, school of materials sciences and technology, china. Jun 14, 2017 xray diffraction analysis of graphite, graphite oxide, and the reduced graphene oxide was carried out using rigaku ultima iv xray diffractometer with cu ka 1 radiation. 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 kmno 4 to graphite. Generally, an electron energy gap could be varied by oxidation of graphene, and the value of the energy gap depends on oxidization degree. Raman spectra was recorded with a labram hr800 microraman spectroscope horiba jobinyvon, france operated at 4. Xrd patterns also showed the formation of graphene oxide material. Uvvis light induced photocatalytic activity of tio2graphene. Nanographene oxide for cellular imaging and drug delivery. Reduced graphenetio 2 solution was spin coated over fto glass 15. Graphene oxide go sheets, a single layer of carbon atoms which can be served as substrates for fabricating metallic nanoparticlesgo nanocomposites. The morphology, diameter, stability and uv vis absorbance of reducedngo were detected firstly. On the other hand, exfoliated graphene oxide go is the ideal alternative for the production of solution processable graphene. Ultrasensitive selfpowered large area planar gan uv photodetector using reduced graphene oxide electrodes nisha prakash 1,2, manjri singh 1,2, gaurav kumar 1, arun barvat 1,2, kritika anand 1,2, prabir pal 1,2, surinder p. The strong peak at corresponds to an interlayer spacing of about 0.
Transparent and conductive graphene oxidepolyethylenglycol diacrylate coatings obtained by photopolymerization m. This is convenient but the effect of the size of go on the accuracy of this method has been ignored so far. Aug 18, 2019 exfoliation experiments were conducted both for odcontaining graphene oxide and odstripped graphene oxide samples, basewashed go bwgo, in order to detect the effect of oxidative debris on agglomeration of graphene layers. Research article preparation and characterization of. Xray diffraction of graphene oxide and reduced graphene oxide synthesized by chemical reduction of exfoliated and intercalated graphite oxide is presented in figure 2. Graphene oxide go has recently attracted great attention due to its unique chemical and physical properties. As a derivatives of graphene, graphene oxide go, which could be detected to have hydroxyl, carbonyl, carboxyl and epoxide functional groups on thesurfaces of each shee 3. Jul 27, 2017 in this work, different sizes of graphite flakes for preparation of graphene oxide go were tested and the final characterization of the resulting go was focused on a quick and reliable methods such as raman and uv vis spectroscopy, atomic force microscopy, and surface plasmon resonance.
Transparent and conductive graphene oxidepolyethylenglycol. Having unique properties, graphene layers are a quite interesting nanomaterial for industrial applications. In this work, the go nanosheets were prepared by a chemical exfoliation technique. Xray photoelectron spectra xps show that the change of uvvis absorption intensity of. Advanced chemical reduction of reduced graphene oxide. The resulted rgo nanoparticles were characterized using ultravioletvisible spectrophotometry uvvis, xray powder diffraction. Effective strategy was studied to produce graphene. Uvassisted reduction of graphene oxide was performed by 450 w xenon arc lamp for about 2 h. Both graphene oxide and reduced graphene oxide were characterized by uv visible spectroscopy, ftir spectroscopy, and xrd techniques. Uv assisted photocatalytic synthesis of tio2reduced graphene oxide with enhanced photocatalytic activity in decomposition of sarin in gas phase. Impedance spectra implied a decreased backtransport reaction of electrons.
Electrochemically reduced graphene oxide sheets for use in. According to the absorbance spectra, the main spectrum of graphene oxide has an strong absorption peak at 233 nm, attributed to transition of the cc conjugated aromatic domains and weak absorption shoulder at 305 nm due to. 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. The authors report that the molar absorbance of go is sizedependent. Uvvis light induced photocatalytic activity of tio2. Synthesis of reduced graphene oxidetitanium rgotio 2 composite using a solvothermal and hydrothermal methods and characterized via xrd and uv vis huzaikha awang, nurul infaza talalah ppstums sabah malaysia, uitm pahang malaysia, jengka, pahang, malaysia abstract nowadays, carbon capture and conversion ccc method one of the alis ter. Reducing graphene oxide is a costeffective and scalable route for producing high quality carbon materials with tunable carbontooxygen co ratios. Fabrication and photocatalytic properties of tio2reduced. Synthesis and characterization of graphene thin films by. The prepared samples were characterized by scanning. Abstract tio2reduced graphene oxide rgo composite are successfully prepared by uvassisted photocatalytic reduction of graphite oxide by tio2 nanoparticles in ethanol. According to the absorbance spectra, the main spectrum of graphene oxide has an strong absorption peak at 233 nm, attributed to transition of the cc conjugated aromatic domains and. Pdf ultravioletvisible spectroscopy of graphene oxides. The spectra in figures 2a and 2b show two peaks corresponding to graphene oxide and graphene.
The result showed that better oxidation degree of graphite powder was obtained by treating 0. However, once most of the oxygen groups are removed, the reduced graphene oxide rgo obtained is more difficult to. In different graphite forms two major absorbance peaks are observed at 223 nm and 273 nm corresponding to graphene oxide and graphene dispersions, respectively. Graphene and its oxides have attracted much attention because of their interesting electronic properties.
The uv region ranges from 190 to 400 nm and the visible region from 400 to 800 nm. Surface activation of graphene oxide nanosheets by. Graphene oxide and reduced graphene oxide were characterized by. Graphene oxide was synthesised by modified hummers method. These nanocomposites prepared with different ratios of graphene oxide go were characterized by scanning electron microscopy, transmission electron microscopy, xray diffraction spectroscopy, uv vis. Conversely, the transparent graphene oxide exhibits a weaker absorption band centered nearby 290 nm. Uvassisted photocatalytic synthesis of tio2reduced graphene. The absorption or graphene in uv to visible region has been investigated by uv vis spectroscopy which is shown in figure 8. Figure 2 optical properties of nanographene oxide sheets. To address this issue various graphite forms solid, powder and sooth and graphite oxide powder are exfoliated in acetonitrile and studied via ultraviolet visible uv vis spectroscopy. Research article preparation and characterization of graphene. Nahid pervez 1,2,3, wei he 1, tiziano zarra 2, vincenzo naddeo 2, and yaping zhao 1, 1 school of ecological and environmental science, shanghai key laboratory for urban ecological process and ecorestoration, east china normal university. Since aunps anchored on graphene families could exhibit interesting catalytic, electrical and optical activities 2, 5, 8, 10, 11, 20, understanding the nature and extent of morphological transformation of gold nanoparticlegraphene oxide aunpgo hybrids could maximize their potentials for many practical applications 1823. The electrochemically reduced graphene oxide ergo was characterized by uv vis, eis and zetapotential measurements.
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