Incorporation of reduced graphene oxide into faceted flower-like {001} TiO
            2
            for enhanced photocatalytic activity

Anatase TiO 2 with {001} facets is much more active than that with {101} facets, which has been verified via experiments and theoretical calculations. Graphene has garnered much attention since it was initially synthesized, due to its unique properties. In this study, reduced graphene oxide (RGO)/{001} faceted TiO 2 composites were fabricated via a solvothermal method. The composites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectrophotometry, photoluminescence and Raman analysis. The results revealed that the graphene oxide was reduced during the preparation process of the {001} faceted TiO 2 , and combined with the surface of {001} TiO 2 . The photocatalytic activities of the composites were evaluated through the degradation of basic violet, under both white light ( λ > 390 nm) and visible light ( λ = 420 nm) irradiation. The results indicated that the photocatalytic activities of the {001} faceted TiO 2 were significantly improved following the incorporation of RGO, particularly under visible light irradiation. Theoretical calculations showed that the band structure of the {001} faceted TiO 2 was modified via graphene hybridization, where the separation of photoinduced electron–hole pairs was promoted; thus, the photocatalytic activity was enhanced.

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Reduced Graphene Oxide–Epoxy Grafted Poly(Styrene-Co-Acrylate) Composites for Corrosion Protection of Mild Steel

Coatings ◽

10.3390/coatings9100666 ◽

2019 ◽

Vol 9 (10) ◽

pp. 666

Author(s):

Xinchuan Fan ◽

Yue Hu ◽

Yijun Zhang ◽

Jiachen Lu ◽

Xiaofeng Chen ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

X Ray Diffraction ◽

Corrosion Properties ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Scanning Electron

Reduced graphene oxide–epoxy grafted poly(styrene-co-acrylate) composites (GESA) were prepared by anchoring different amount of epoxy modified poly(styrene-co-acrylate) (EPSA) onto reduced graphene oxide (rGO) sheets through π–π electrostatic attraction. The GESA composites were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The anti-corrosion properties of rGO/EPSA composites were evaluated by electro-chemical impedance spectroscopy (EIS) in hydroxyl-polyacrylate coating, and the results revealed that the corrosion rate was decreased from 3.509 × 10−1 to 1.394 × 10−6 mm/a.

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Facile Fabrication of CeO2/Electrochemically Reduced Graphene Oxide Nanocomposites for Vanillin Detection in Commercial Food Products

Nanomaterials ◽

10.3390/nano10071356 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1356 ◽

Cited By ~ 2

Author(s):

Xue Nie ◽

Rui Zhang ◽

Zheng Tang ◽

Haiyan Wang ◽

Peihong Deng ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Linear Sweep Voltammetry ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Electrochemically Reduced Graphene Oxide ◽

Wide Range ◽

Facile Fabrication

In this paper, CeO2 nanoparticles were synthesized by the solvothermal method and dispersed uniformly in graphene oxide (GO) aqueous solution by ultrasonication. The homogeneous CeO2-GO dispersion was coated on the surface of a glassy carbon electrode (GCE), and the CeO2/electrochemically reduced graphene oxide modified electrode (CeO2/ERGO/GCE) was obtained by potentiostatic reduction. The results of X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) showed that CeO2 nanocrystals were uniformly coated by gossamer like ERGO nanosheets. The electrochemical behavior of vanillin on the CeO2/ERGO/GCE was studied by cyclic voltammetry (CV). It was found that the CeO2/ERGO/GCE has high electrocatalytic activity and good electrochemical performance for vanillin oxidation. Using the second derivative linear sweep voltammetry (SDLSV), the CeO2/ERGO/GCE provides a wide range of 0.04–20 µM and 20 µM–100 µM for vanillin detection, and the detection limit is estimated to be 0.01 µM after 120 s accumulation. This method has been successfully applied to the vanillin detection in some commercial foods.

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Ce2O3/BiVO4 Embedded in rGO as Photocatalyst for the Degradation of Methyl Orange under Visible Light Irradiation

J ◽

10.3390/j4020013 ◽

2021 ◽

Vol 4 (2) ◽

pp. 154-168

Author(s):

Damian C. Onwudiwe ◽

Boitumelo M. Phadi ◽

Opeyemi A. Oyewo

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Graphene Oxide ◽

Methyl Orange ◽

Visible Light ◽

Reduced Graphene Oxide ◽

Visible Light Irradiation ◽

Light Irradiation ◽

Reduced Graphene ◽

Degradation Of Methyl Orange

A p–n heterojunction semiconductor structure composed of Ce3O4 and BiVO4 has been synthesized and then incorporated into reduced graphene oxide (rGO) by the hydrothermal method. The ternary composites were characterized by X-ray diffraction, transmission electron microscopy (TEM), scanning electron microscopy (SEM), electron diffraction spectroscopy (EDS), and UV–vis spectroscopy. The efficiency of the composites as photocatalysts was determined by studying the oxidative degradation of methyl orange in aqueous solution under visible light irradiation. The effect of parameters such as pH, catalyst loading, and concentration of the dye solution was examined in order to determine their influence on the photocatalytic activity of the composites. The composite incorporated into reduced graphene oxide presented the highest percentage (above 90%) in 2 h time, attributed to the effect of the increased surface area. The process of the enhanced photocatalytic activity has been discussed based on the energy band positions of the nanoparticles within the composite.

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Ionic liquid-assisted hydrothermal synthesis of Bi2WO6–reduced graphene oxide composites with enhanced photocatalytic activity

RSC Advances ◽

10.1039/c4ra11276h ◽

2014 ◽

Vol 4 (108) ◽

pp. 63238-63245 ◽

Cited By ~ 18

Author(s):

Hua Lv ◽

Yumin Liu ◽

Jiayuan Hu ◽

Zijin Li ◽

Yan Lu

Keyword(s):

Ionic Liquid ◽

Photocatalytic Activity ◽

Graphene Oxide ◽

Hydrothermal Synthesis ◽

Visible Light ◽

Reduced Graphene Oxide ◽

Visible Light Irradiation ◽

Reduced Graphene ◽

Photocatalytic Activities ◽

Oxide Composites

Due to the synergistic contributions of graphene and ionic liquid, the as-prepared RGO–Bi2WO6 samples exhibited the remarkably enhanced photocatalytic activities under visible light irradiation.

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Solvothermal preparation of phthalocyanine nanorod/rGO composites and their application to visible-light-responsive photocatalysts

Functional Materials Letters ◽

10.1142/s1793604716500648 ◽

2016 ◽

Vol 09 (05) ◽

pp. 1650064 ◽

Cited By ~ 1

Author(s):

Shuai Zhang ◽

Yongting Lu ◽

Fan Zhang ◽

Jie Qu ◽

Bencai Lin ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Graphene Oxide ◽

Visible Light ◽

Average Diameter ◽

Amorphous Structure ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Reduced Graphene ◽

Solvothermal Preparation

Phthalocyanine (Pc) nanorod/reduced graphene oxide (rGO) composites were prepared by a simple solvothermal method, in which Pc nanosheet and graphene oxide (GO) suspensions were mixed in methanol. As characterized by scanning electron microscopy, transmission electron microscopy, and selected area electron diffraction, Pc nanorods with an amorphous structure and an average diameter of 250[Formula: see text]nm are partially covered by rGO sheets. In the photodegradation experiments, all the composites with different rGO content show enhanced photocatalytic activity for Rhodamine B decomposition under visible-light compared to pure Pc nanorods or rGO sheets. The enhanced photocatalytic activity shall be ascribed to the large surface area offered by rGO and the charge-transfer from Pc to rGO as indicated by the photoluminescence measurement, in which fluorescence intensity of the composites is much weaker than that of Pc nanorods.

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Zirconia Reduced Graphene Oxide Nano-Hybrid Structure Fabricated by the Hydrothermal Reaction Method

Materials ◽

10.3390/ma13030687 ◽

2020 ◽

Vol 13 (3) ◽

pp. 687 ◽

Cited By ~ 4

Author(s):

Anton Smirnov ◽

Nestor Washington Solís Pinargote ◽

Nikita Peretyagin ◽

Yuri Pristinskiy ◽

Pavel Peretyagin ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Hydrothermal Reaction ◽

Hybrid Structure ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Nanocomposite Powders

In this work, we report an available technique for the effective reduction of graphene oxide (GO) and the fabrication of nanostructured zirconia reduced graphene oxide powder via a hydrothermal method. Characterization of the obtained nano-hybrid structure materials was carried out using a scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR). The confirmation that GO was reduced and the uniform distribution of zirconia nanoparticles on graphene oxide sheets during synthesis was obtained due to these techniques. This has presented new opportunities and prospects to use this uncomplicated and inexpensive technique for the development of zirconia/graphene nanocomposite powders.

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Reduced graphene oxide supported C3N4 nanoflakes and quantum dots as metal-free catalysts for visible light assisted CO2 reduction

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.44 ◽

2019 ◽

Vol 10 ◽

pp. 448-458 ◽

Cited By ~ 5

Author(s):

Md Rakibuddin ◽

Haekyoung Kim

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Visible Light ◽

Reduced Graphene Oxide ◽

Hybrid Materials ◽

Photoelectron Spectroscopy ◽

X Ray ◽

Metal Free ◽

Reduced Graphene ◽

Vis Spectroscopy

The visible light photocatalytic reduction of CO2 to fuel is crucial for the sustainable development of energy resources. In our present work, we report the synthesis of novel reduced graphene oxide (rGO)-supported C3N4 nanoflake (NF) and quantum dot (QD) hybrid materials (GCN) for visible light induced reduction of CO2. The C3N4 NFs and QDs are prepared by acid treatment of C3N4 nanosheets followed by ultrasonication and hydrothermal heating at 130–190 °C for 5−20 h. It is observed that hydrothermal exposure of acid-treated graphitic carbon nitride (g-C3N4) nanosheets at low temperature generated larger NFs, whereas QDs are formed at higher temperatures. The formation of GCN hybrid materials was confirmed by powder X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy (TEM), and UV–vis spectroscopy. High-resolution TEM images clearly show that C3N4 QDs (average diameter of 2–3 nm) and NFs (≈20–45 nm) are distributed on the rGO surface within the GCN hybrid material. Among the as-prepared GCN hybrid materials, GCN-5 QDs exhibit excellent CO2 reductive activity for the generation of formaldehyde, HCHO (10.3 mmol h−1 g−1). Therefore, utilization of metal-free carbon-based GCN hybrid materials could be very promising for CO2 photoreduction because of their excellent activity and environmental sustainability.

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Pd Nanoparticles Incorporated Within a Zr-Based Metal–Organic Framework/Reduced Graphene Oxide Multifunctional Composite for Efficient Visible-Light-Promoted Benzyl Alcohol Oxidation

Australian Journal of Chemistry ◽

10.1071/ch18387 ◽

2019 ◽

Vol 72 (5) ◽

pp. 334

Author(s):

Ting Li ◽

Tian Tian ◽

Fangyuan Chen ◽

Xiang Liu ◽

Xiaohua Zhao

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Graphene Oxide ◽

Visible Light ◽

Benzyl Alcohol ◽

Reduced Graphene Oxide ◽

Pd Nanoparticles ◽

Oxidation Reactions ◽

Reduced Graphene ◽

Metal Organic

Metal–organic frameworks (MOFs) in photocatalysis oxidation reactions have been arousing great interest because of their unique properties. Zr-based MOFs (mainly 1,4-dicarboxybenzene MOF (UiO-66)) appear to be very attractive candidates. In this study, a Pd@UiO-66/reduced graphene oxide (rGO) nanocomposite was successfully prepared via a facile solvothermal method and was characterised by several techniques, including field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), nitrogen adsorption–desorption isotherms, and photoluminescence (PL) spectroscopy. Subsequently, the as-obtained Pd@UiO-66/rGO composite was used as a photocatalyst for the selective oxidation of benzyl alcohol to benzaldehyde with O2 under visible light irradiation (>420nm); it exhibited superior photocatalytic activity due to the synergistic effect of coupling Pd nanoparticles (NPs) with UiO-66 and rGO. Importantly, the Pd@UiO-66/rGO composite showed high stability and considerable recyclability to preserve most of its initial photocatalytic activity after five cycles of the oxidation reaction.

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Hydrogen Peroxide Assisted Photocatalytic Dye Degradation Over Reduced Graphene Oxide Integrated ZnCr2O4 Nanoparticles

10.21203/rs.3.rs-794253/v1 ◽

2021 ◽

Author(s):

Kartik Tantubay ◽

Piu Das ◽

Moni Baskey (Sen)

Keyword(s):

Electron Microscopy ◽

Hydrogen Peroxide ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Dye Degradation ◽

Structural Morphology ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Zinc Chromite

Abstract Zinc chromite nanoparticles (NPs) and zinc chromite-reduced graphene oxide (ZnCr2O4-rGO) nanocomposite have been synthesized by the combined effect of reflux condensation and calcination process. The structural properties were characterised by X-ray diffraction (XRD), Fourier transform infrared (FTIR), UV-visible studies etc. Structural morphology was investigated by field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) that indicates the formation of particles in nanometre regime. The catalytic effects of synthesized materials were studied in presence of visible light assisted by hydrogen peroxide (H2O2) and they show excellent photo activity which supports the band gap value and photoluminescence outcome. The presence of the elements Zn, Cr, O and C has been confirmed by Energy dispersive X-ray spectroscopy (EDX) images which show the purity of the synthesized products.

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Few-Layered MoS2 Nanostructures for Highly Efficient Visible Light Photocatalysis

NANO ◽

10.1142/s1793292016501149 ◽

2016 ◽

Vol 11 (10) ◽

pp. 1650114 ◽

Cited By ~ 5

Author(s):

Dan Li ◽

Jianwei Li ◽

Caiqin Han ◽

Xinsheng Zhao ◽

Haipeng Chu ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Visible Light ◽

Electrochemical Impedance ◽

X Ray Diffraction ◽

Electron Hole ◽

Electrochemical Impedance Spectra ◽

X Ray ◽

Transmission Electron ◽

Electron Hole Pair

Few-layered MoS2 nanostructures were successfully synthesized by a simple hydrothermal method without the addition of any catalysts or surfactants. Their morphology, structure and photocatalytic activity were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, electrochemical impedance spectra and UV-Vis absorption spectroscopy, respectively. These results show that the MoS2 nanostructures synthesized at 180[Formula: see text]C exhibit an optimal visible light photocatalytic activity (99%) in the degradation of Rhodamine B owing to the relatively easier adsorption of pollutants, higher visible light absorption and lower electron–hole pair recombination.

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