Cross-Linking With Diamine Monomers to Prepare Graphene Oxide Composite Membranes With Varying D-Spacing for Enhanced Desalination Properties

As a new type of membrane material, graphene oxide (GO) can easily form sub-nanometer interlayer channels, which can effectively screen salt ions. The composite membrane and structure with a high water flux and good ion rejection rate were compared by the cross-linking of GO with three different diamine monomers: ethylenediamine (EDA), urea (UR), and p-phenylenediamine (PPD). X-ray photoelectron spectroscopy (XPS) results showed that unmodified GO mainly comprises π-π interactions and hydrogen bonds, but after crosslinking with diamine, both GO and mixed cellulose (MCE) membranes are chemically bonded to the diamine. The GO-UR/MCE membrane achieved a water flux similar to the original GO membrane, while the water flux of GO-PPD/MCE and GO-EDA/MCE dropped. X-ray diffraction results demonstrated that the covalent bond between GO and diamine can effectively inhibit the extension of d-spacing during the transition between dry and wet states. The separation performance of the GO-UR/MCE membrane was the best. GO-PPD/MCE had the largest contact angle and the worst hydrophilicity, but its water flux was still greater than GO-EDA/MCE. This result indicated that the introduction of different functional groups during the diamine monomer cross-linking of GO caused some changes in the performance structure of the membrane.

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Chemically Cross-Linked Graphene Oxide as a Selective Layer on Electrospun Polyvinyl Alcohol Nanofiber Membrane for Nanofiltration Application

Nanomaterials ◽

10.3390/nano11112867 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2867

Author(s):

Myoung Jun Park ◽

Grace M. Nisola ◽

Dong Han Seo ◽

Chen Wang ◽

Sherub Phuntsho ◽

...

Keyword(s):

Graphene Oxide ◽

Polyvinyl Alcohol ◽

Self Assembly ◽

Water Flux ◽

Composite Membranes ◽

Cross Linking ◽

Support Surface ◽

Eosin Y ◽

Selective Layer ◽

Assembly Technique

Graphene oxide (GO) nanosheets were utilized as a selective layer on a highly porous polyvinyl alcohol (PVA) nanofiber support via a pressure-assisted self-assembly technique to synthesize composite nanofiltration membranes. The GO layer was rendered stable by cross-linking the nanosheets (GO-to-GO) and by linking them onto the support surface (GO-to-PVA) using glutaraldehyde (GA). The amounts of GO and GA deposited on the PVA substrate were varied to determine the optimum nanofiltration membrane both in terms of water flux and salt rejection performances. The successful GA cross-linking of GO interlayers and GO-PVA via acetalization was confirmed by FTIR and XPS analyses, which corroborated with other characterization results from contact angle and zeta potential measurements. Morphologies of the most effective membrane (CGOPVA-50) featured a defect-free GA cross-linked GO layer with a thickness of ~67 nm. The best solute rejections of the CGOPVA-50 membrane were 91.01% for Na2SO4 (20 mM), 98.12% for Eosin Y (10 mg/L), 76.92% for Methylene blue (10 mg/L), and 49.62% for NaCl (20 mM). These findings may provide one of the promising approaches in synthesizing mechanically stable GO-based thin-film composite membranes that are effective for solute separation via nanofiltration.

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The Variations of Structure and Water Flux Performance of Porous Alumina Supported Graphene Oxide Membrane During Heat Treatment Process

Nanoscience and Nanotechnology Letters ◽

10.1166/nnl.2019.2920 ◽

2019 ◽

Vol 11 (5) ◽

pp. 611-620

Author(s):

Xinying Qiao ◽

Jianguo Huang ◽

Weidong Li ◽

Mintao Gou ◽

Yangyang Han ◽

...

Keyword(s):

Heat Treatment ◽

Graphene Oxide ◽

Thermal Treatment ◽

Pure Water ◽

Water Flux ◽

Composite Membranes ◽

Ceramic Substrate ◽

Oxide Ceramic ◽

X Ray ◽

Oxide Membrane

Graphene oxide membrane was fabricated based on a silane-modified Al2O3 ceramic substrate via a parallel dip-coating method. The effect of thermal treatment on the structure and performance of graphene oxide membranes was mainly studied in this paper. The thermal behaviours of graphene oxide powder and membranes were analysed by thermogravimetry (TG) and differential scanning calorimetry (DSC). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were applied for micro-morphology analysis. The category and content of chemical bonds were studied by fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS), and the interplanar spacing was investigated by X-ray diffraction (XRD). It was found that the thermal treatment temperature should not exceed 350 °C in order to ensure the integrity of the graphene oxide basic structure. The content of functional groups in graphene oxide was altered along with various temperatures, which led to changes in the contact angle and hydrophilicity. The pure water flux reached 15 L m–2 h –1 under 0.2 MPa pressure when the ceramic substrate was coated with 0.5 mg/mL graphene oxide dispersion and treated at 190 °C. The study indicates that the performance of the graphene oxide/ceramic composite membranes can be optimized by heat treatment.

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Covalent Functionalization of Graphene Oxide with Fructose, Starch, and Micro-Cellulose by Sonochemistry

Polymers ◽

10.3390/polym13040490 ◽

2021 ◽

Vol 13 (4) ◽

pp. 490

Author(s):

María Montserrat Cruz-Benítez ◽

Pablo Gónzalez-Morones ◽

Ernesto Hernández-Hernández ◽

José Roberto Villagómez-Ibarra ◽

Javier Castro-Rosas ◽

...

Keyword(s):

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Organic Molecules ◽

Chemical Characterization ◽

Covalent Bond ◽

X Ray Diffraction ◽

X Ray ◽

Ultrasound Waves ◽

Short Time

In this work, we report the synthesis of graphene oxide (GO) nanohybrids with starch, fructose, and micro-cellulose molecules by sonication in an aqueous medium at 90 °C and a short reaction time (30 min). The final product was washed with solvents to extract the nanohybrids and separate them from the organic molecules not grafted onto the GO surface. Nanohybrids were chemically characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy and analyzed by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). These results indicate that the ultrasound energy promoted a chemical reaction between GO and the organic molecules in a short time (30 min). The chemical characterization of these nanohybrids confirms their covalent bond, obtaining a grafting percentage above 40% the weight in these nanohybrids. This hybridization creates nanometric and millimetric nanohybrid particles. In addition, the grafted organic molecules can be crystallized on GO films. Interference in the ultrasound waves of starch hybrids is due to the increase in viscosity, leading to a partial hybridization of GO with starch.

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Long-Term Stable 1-butyl-3-methylimidazolium Hexafluorophosphate/Ag Metal Composite Membranes for Facilitated Olefin Transport

Membranes ◽

10.3390/membranes10080191 ◽

2020 ◽

Vol 10 (8) ◽

pp. 191 ◽

Cited By ~ 1

Author(s):

Sang Wook Kang

Keyword(s):

Ionic Liquid ◽

Phase Separation ◽

Composite Membrane ◽

Photoelectron Spectroscopy ◽

Composite Membranes ◽

Separation Performance ◽

Metal Composite ◽

X Ray ◽

Long Term Stability

For the preparation of long-term stable ionic liquid/Ag nanoparticles composites, we compared the separation performance of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM+BF4−)/Ag, and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM+PF6−)/Ag composite membranes with time. Separation performance showed that the BMIM+PF6−/Ag metal composite membrane was more stable than the BMIM+BF4−/Ag metal composite membrane for more than 160 h. These differences in long-term stability in BMIM+PF6−/Ag and BMIM+BF4−/Ag metal composite membranes was attributable to the phase separation between ionic liquid and nanoparticles. In particular, the phase separation between ionic liquid and silver nanoparticles was not observed with time in hydrophobic ionic liquid BMIM+PF6−, confirmed by X-ray photoelectron spectroscopy.

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X-ray Photoelectron Spectroscopy Analysis of Chitosan–Graphene Oxide-Based Composite Thin Films for Potential Optical Sensing Applications

Polymers ◽

10.3390/polym13030478 ◽

2021 ◽

Vol 13 (3) ◽

pp. 478

Author(s):

Wan Mohd Ebtisyam Mustaqim Mohd Daniyal ◽

Yap Wing Fen ◽

Silvan Saleviter ◽

Narong Chanlek ◽

Hideki Nakajima ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Functional Group ◽

Optical Sensing ◽

Composite Thin Films ◽

Cobalt Ions ◽

X Ray ◽

Sensing Applications

In this study, X-ray photoelectron spectroscopy (XPS) was used to study chitosan–graphene oxide (chitosan–GO) incorporated with 4-(2-pyridylazo)resorcinol (PAR) and cadmium sulfide quantum dot (CdS QD) composite thin films for the potential optical sensing of cobalt ions (Co2+). From the XPS results, it was confirmed that carbon, oxygen, and nitrogen elements existed on the PAR–chitosan–GO thin film, while for CdS QD–chitosan–GO, the existence of carbon, oxygen, cadmium, nitrogen, and sulfur were confirmed. Further deconvolution of each element using the Gaussian–Lorentzian curve fitting program revealed the sub-peak component of each element and hence the corresponding functional group was identified. Next, investigation using surface plasmon resonance (SPR) optical sensor proved that both chitosan–GO-based thin films were able to detect Co2+ as low as 0.01 ppm for both composite thin films, while the PAR had the higher binding affinity. The interaction of the Co2+ with the thin films was characterized again using XPS to confirm the functional group involved during the reaction. The XPS results proved that primary amino in the PAR–chitosan–GO thin film contributed more important role for the reaction with Co2+, as in agreement with the SPR results.

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Enhanced Water Resistance of Recycled Newspaper/High Density Polyethylene Composite Laminates via Hydrophobic Modification of Newspaper Laminas

Polymers ◽

10.3390/polym13030421 ◽

2021 ◽

Vol 13 (3) ◽

pp. 421

Author(s):

Binwei Zheng ◽

Weiwei Zhang ◽

Litao Guan ◽

Jin Gu ◽

Dengyun Tu ◽

...

Keyword(s):

Stearic Acid ◽

Photoelectron Spectroscopy ◽

Composite Laminates ◽

High Density Polyethylene ◽

Water Resistance ◽

Laminated Composite ◽

High Strength ◽

High Water ◽

High Density ◽

X Ray

A high strength recycled newspaper (NP)/high density polyethylene (HDPE) laminated composite was developed using NP laminas as reinforcement and HDPE film as matrix. Herein, NP fiber was modified with stearic acid (SA) to enhance the water resistance of the NP laminas and NP/HDPE composite. The effects of heat treatment and SA concentration on the water resistance and tensile property of NP and composite samples were investigated. The chemical structure of the NP was characterized with X-ray diffractometer, X-ray photoelectron spectroscopy and attenuated total reflectance Fourier transform infrared spectra techniques. The surface and microstructure of the NP sheets were observed by scanning electron microscopy. An expected high-water resistance of NP sheets was achieved due to a chemical bonding that low surface energy SA were grafted onto the modified NP fibers. Results showed that the hydrophobicity of NP increased with increasing the stearic acid concentration. The water resistance of the composite laminates was depended on the hydrophobicity of the NP sheets. The lowest value of 2 h water absorption rate (3.3% ± 0.3%) and thickness swelling rate (2.2% ± 0.4%) of composite were obtained when the SA concentration was 0.15 M. In addition, the introduction of SA can not only enhance the water resistance of the composite laminates, but also reduce the loss of tensile strength in wet conditions, which shows potential in outdoor applications.

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Polyvinylamine/graphene oxide/PANI@CNTs mixed matrix composite membranes with enhanced CO2/N2 separation performance

Journal of Membrane Science ◽

10.1016/j.memsci.2019.117246 ◽

2019 ◽

Vol 589 ◽

pp. 117246 ◽

Cited By ~ 12

Author(s):

Yonghong Wang ◽

Long Li ◽

Xinru Zhang ◽

Jinping Li ◽

Chengcen Liu ◽

...

Keyword(s):

Graphene Oxide ◽

Matrix Composite ◽

Composite Membranes ◽

Separation Performance ◽

Mixed Matrix

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X-Ray Photoelectron Spectroscopy Study on Reduction of Graphene Oxide with Hydrazine Hydrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.539 ◽

2011 ◽

Vol 287-290 ◽

pp. 539-543 ◽

Cited By ~ 5

Author(s):

Wen Shi Ma ◽

Jun Wen Zhou ◽

Xiao Dan Lin

Keyword(s):

Graphene Oxide ◽

Hydrazine Hydrate ◽

Photoelectron Spectroscopy ◽

Reduction Rate ◽

Reduction Reaction ◽

Chemical Compositions ◽

Total Oxygen ◽

Graphene Oxides ◽

X Ray ◽

Oxygen Groups

Graphene oxide was prepared through Hummers' method，then different reduced graphenes were prepared via reduction of graphene oxide with hydrazine hydrate for 1h、12h and 24h. X-ray photoelectron spectroscopy (XPS) was used for the characterization of graphene oxide and the reduced graphenes. The variation of the contents of carbon in carbon and oxygen functional groups and chemical compositions of graphene oxides were investigated through analysis the content of different carbon atoms in different reduced graphenes. The results showed that the reduction reaction was very fast in the first 1 h, the content of total oxygen bonded carbon atoms decreased from 83.6% to 22.1%, and then after the reduction rate became very slow. After 12h, the content of total oxygen bonded carbon atom is 19.56%, only 2.54% lower than that of 1h’s. At the same time, C-N was introduced in the graphene oxides; this increased the stereo-hindrance for hydrazine hydrate attacking the C-Oxygen groups, thus reduced the reduction rate. After reduction for 24h, there still exists 16.4% oxygen bonded carbon atoms and the total conversion ratio of graphene approaches 70%.

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Ternary Composite of Molybdenum Disulfide-Graphene Oxide-Polyaniline for Supercapacitor

Journal of The Electrochemical Society ◽

10.1149/1945-7111/ac3f1e ◽

2021 ◽

Author(s):

Ke Qu ◽

Yuqi Bai ◽

Miao Deng

Keyword(s):

Graphene Oxide ◽

Molybdenum Disulfide ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Light Emitting Diode ◽

Rate Capability ◽

Energy Storage And Conversion ◽

Carbon Paper ◽

Power Sources ◽

X Ray

Abstract The ever-increasing need for small and lightweight power sources for use in portable or wearable electronic devices has spurred the development of supercapacitors as a promising energy storage and conversion system. In this work, a simple, facile and easy-to-practice method has been developed to employ carbon paper (CP) as the support to coat molybdenum disulfide (MoS2) and graphene oxide (GO), followed by electrodeposition of polyaniline (PANI) to render CP/MoS2-GO-PANI. The preparation parameters, such as amounts of MoS2, GO and number of aniline electropolymerization cycles, have been optimized to render CP/MoS2-GO-PANI the best capacitive performance. The as-prepared optimal CP/MoS2-GO-PANI is characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive spectroscopy, and X-ray photoelectron spectroscopy. The supercapacitive properties of CP/MoS2-GO-PANI as an electrode have been evaluated electrochemically via cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy testing. CP/MoS2-GO-PANI delivers a specific capacitance of 255.1 F/g at 1.0 A/g and exhibits excellent rate capability under larger current densities. Moreover, a symmetrical supercapacitor is assembled and three are connected in series to power a light-emitting diode for ~15 minutes, demonstrating the promising application potential of CP/MoS2-GO-PANI-based supercapacitor.

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Characterization of X-ray irradiated graphene oxide coatings using X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy

Powder Diffraction ◽

10.1017/s0885715613000109 ◽

2013 ◽

Vol 28 (2) ◽

pp. 68-71 ◽

Cited By ~ 40

Author(s):

Thomas N. Blanton ◽

Debasis Majumdar

Keyword(s):

Atomic Force Microscopy ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

High Energy ◽

X Ray Diffraction ◽

Carbon Phase ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Before And After

In an effort to study an alternative approach to make graphene from graphene oxide (GO), exposure of GO to high-energy X-ray radiation has been performed. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) have been used to characterize GO before and after irradiation. Results indicate that GO exposed to high-energy radiation is converted to an amorphous carbon phase that is conductive.

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