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

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

Royal Society Open Science ◽

10.1098/rsos.180613 ◽

2018 ◽

Vol 5 (8) ◽

pp. 180613 ◽

Cited By ~ 3

Author(s):

Haijin Liu ◽

Peiyao Li ◽

Haokun Bai ◽

Cuiwei Du ◽

Dandan Wei ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Graphene Oxide ◽

Visible Light ◽

Reduced Graphene Oxide ◽

Theoretical Calculations ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Photocatalytic Activities

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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One-Step Solvothermal Synthesis of Tetranitro-Cobalt Phthalocyanine/Reduced Graphene Oxide Composite

NANO ◽

10.1142/s1793292015500459 ◽

2015 ◽

Vol 10 (03) ◽

pp. 1550045 ◽

Cited By ~ 5

Author(s):

Lijuan Zhang ◽

Hejun Li ◽

Qiangang Fu ◽

Zhanwei Xu ◽

Kezhi Li ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Rotating Disk ◽

Rotating Disk Electrode ◽

Cobalt Phthalocyanine ◽

Transmission Electron ◽

Reduced Graphene ◽

Wide Range ◽

One Step

Tetranitro-cobalt phthalocyanine/reduced graphene oxide (TNCoPc/RGO) composite was prepared using ethylene glycol as reducing agent and precursor. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the composite. The electrochemical performance of the composite was examined by cyclic voltammetry and rotating disk electrode. The SEM observation and UV-Vis absorption spectrophotometer reveal that TNCoPc nanoparticles are closely contacted with RGO. The results show that the composite has a larger peak current and a higher current density than TNCoPc for oxygen reduction in an alkaline medium. This work offers a simple and environmental route for the synthesis of metal phthalocyanine (MPc)/RGO, which is adaptable to a wide range of applications in fuel cells.

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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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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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Reduced Graphene Oxide Supported Molybdenum Oxide Hybrid Nanocomposites: High Performance Electrode Material for Supercapacitor and Photocatalytic Applications

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17779 ◽

2020 ◽

Vol 20 (7) ◽

pp. 4035-4046

Author(s):

Rengasamy Dhanabal ◽

Dhanasekaran Naveena ◽

Sivan Velmathi ◽

Arumugam Chandra Bose

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Hybrid Nanocomposites ◽

X Ray ◽

Supercapacitor Application ◽

Quenching Effect ◽

Reduced Graphene

Using a simple solution based synthesis route, hexagonal MoO3 (h-MoO3) nanorods on reduced graphene oxide (RGO) sheets were prepared. The structure and morphology of resulting RGO-MoO3 nanocomposite were characterized using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). The optical property was studied using UV-Visible diffuse reflectance spectroscopy (UV-Vis DRS) and photoluminescence spectroscopy (PL). The RGO-MoO3 nanocomposites were used as an electrode for supercapacitor application and photocatalyst for photodegradation of methylene blue (MB) and rhodamine B (RhB) under visible light irradiation. We demonstrated that the RGO-MoO3 electrode is capable of delivering high specific capacitance of 134 F/g at current density of 1 A/g with outstanding cyclic stability for 2000 cycles. The RGOMoO3 photocatalyst degrades 95% of MB dye within 90 min, and a considerable recyclability up to 4 cycles was observed. The quenching effect of scavengers test confirms holes are main reactive species in the photocatalytic degradation of MB. Further, the charge transfer process between RGO and MoO3 was schematically demonstrated.

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Facile Synthesis of Modified MnO2/Reduced Graphene Oxide Nanocomposites and their Application in Supercapacitors

NANO ◽

10.1142/s179329202050099x ◽

2020 ◽

Vol 15 (08) ◽

pp. 2050099

Author(s):

Lijun Chen ◽

Hongfeng Yin ◽

Yuchao Zhang ◽

Huidong Xie

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Specific Capacitance ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Electrode Materials ◽

Normal Pressure ◽

X Ray ◽

Assembly Method ◽

Reduced Graphene

Herein, KH-550 was used as surface modifier to prepare modified MnO2/reduced graphene oxide (M-MnO2/rGO) composite electrode materials by utilizing electrostatic interaction at low temperature and normal pressure. X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy were adopted to characterize the material’s phase, morphology, and valence state of elements. The electrochemical properties of the material were measured using a three-electrode system. The results indicate a decrease in the size of the modified MnO2 particles, and that they were uniformly distributed on the rGO sheets. The M-MnO2/rGO composite attained a specific capacitance of 326[Formula: see text]F[Formula: see text]g[Formula: see text] in a solution of 1[Formula: see text]mol[Formula: see text]L[Formula: see text] Na2SO4 at a current density of 0.5[Formula: see text]A[Formula: see text]g[Formula: see text]. The specific capacitance of the material was 92.4% after 1000 cycles. The electrostatic self-assembly method effectively solved the problem of reducing the cycling stability while improving the specific capacitance of the composite materials, and further improved the possibility of applying MnO2/rGO in the field of supercapacitors.

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Co3O4 Nanoparticles-Modified α-MnO2 Nanorods Supported on Reduced Graphene Oxide as Cathode Catalyst for Oxygen Reduction Reaction in Alkaline Media

NANO ◽

10.1142/s1793292016501265 ◽

2016 ◽

Vol 11 (11) ◽

pp. 1650126 ◽

Cited By ~ 16

Author(s):

GuanHua Jin ◽

Suqin Liu ◽

Yaomin Li ◽

Yang Guo ◽

Zhiying Ding

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Catalytic Activity ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Reduced Graphene Oxide ◽

Reduction Reaction ◽

Alkaline Media ◽

X Ray ◽

Reduced Graphene

Development of efficient electrocatalysts for the oxygen reduction reaction (ORR) remains a key issue for the commercialization of metal-air batteries. In this study, the novel structured Co3O4 nanoparticles-modified [Formula: see text]-MnO2 nanorods supported on reduced graphene oxide (Co3O4-MnO2/rGO) were synthesized with varying amounts of [Formula: see text]-MnO2 via a facile two-step hydrothermal method. The relationship between the physical properties and the electrochemical results was investigated using X-ray diffraction spectrum, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammograms, electrochemical impedance spectroscopy and rotating disk electrode. The as-prepared Co3O4–MnO2 nanohybrid exhibits enhanced catalytic activity for ORR under alkaline condition compared with MnO2/rGO and Co3O4/rGO. Furthermore, it mainly favors a direct 4e-reaction pathway for ORR, which is attributed to the well-designed structure, the synergistic effect between Co3O4 and [Formula: see text]-MnO2, and the covalent coupling between the Co3O4-MnO2 and reduced graphene oxide. The role of Co3O4 in Co3O4–MnO2 hybrid for catalyzing ORR also has been illustrated by varying the mass ratio of Co3O4 and MnO2, which reveals that the Co3O4–MnO2 with the ratio of 1:1 has better catalytic activity.

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Photocatalytic Degradation of Organic Pollutant using Reduced Graphene Oxide

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d1165.1284s219 ◽

2019 ◽

Vol 8 (4S2) ◽

pp. 870-872

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Photocatalytic Degradation ◽

Reduced Graphene Oxide ◽

Organic Pollutant ◽

X Ray Diffraction ◽

X Ray ◽

Reduced Graphene ◽

Vis Spectroscopy ◽

Scaning Electron Microscopy

A simple eco friendly preparation of reduced graphene oxide from graphene oxide using strawberry extract is reported. As prepared reduced graphene oxide were characterized by X-Ray Diffraction, UV-Vis spectroscopy, Scaning electron microscopy and degradation performane of MB. The reduced graphene oxide was effectively degradation of MB.

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Facile Synthesis of β-Lactoglobulin-Functionalized Reduced Graphene Oxide and Trimetallic PtAuPd Nanocomposite for Electrochemical Sensing

Nanomaterials ◽

10.3390/nano8090724 ◽

2018 ◽

Vol 8 (9) ◽

pp. 724 ◽

Cited By ~ 4

Author(s):

Bingkai Han ◽

Meixin Pan ◽

Jiexin Zhou ◽

Yingying Wang ◽

Zihua Wang ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Glucose Sensor ◽

Electrochemical Sensing ◽

Facile Synthesis ◽

Serum Samples ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Β Lactoglobulin

The use of graphene has leapt forward the materials field and the functional modification of graphene has not stopped. In this work, β-lactoglobulin (BLG) was used to functionalize reduced graphene oxide (RGO) based on its amphiphilic properties. Also, trimetallic PtAuPd nanoparticles were reduced to the surface of BLG-functionalized RGO and formed BLG-PtAuPd-RGO nanocomposite using facile synthesis. Transmission electron microscopy, energy-dispersive X-ray spectroscopy and Fourier transform infrared spectra were used to characterize the nanocomposite. Electrocatalytic analysis was evaluated through cyclic voltammetry and chronoamperometry methods. We developed a glucose sensor by fabricating GOD-BLG-PtAuPd-RGO/glassy carbon (GC) electrode. It presented a remarkable sensitivity of 63.29 μA mM−1 cm−2 (4.43 μA mM−1), a wider linear range from 0.005 to 9 mM and a lower detection limit of 0.13 μM (S/N = 3). Additionally, the glucose sensor exhibited excellent testing capability in human serum samples.

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