Free-Standing Graphene Oxide and Carbon Nanotube Hybrid Papers with Enhanced Electrical and Mechanical Performance and Their Synergy in Polymer Laminates

Hybrid nanomaterials fabricated by the heterogeneous integration of 1D (carbon nanotubes) and 2D (graphene oxide) nanomaterials showed synergy in electrical and mechanical properties. Here, we reported the infiltration of carboxylic functionalized single-walled carbon nanotubes (C-SWNT) into free-standing graphene oxide (GO) paper for better electrical and mechanical properties than native GO. The stacking arrangement of GO sheets and its alteration in the presence of C-SWNT were comprehensively explored through scanning electron microscopy, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction. The C-SWNTs bridges between different GO sheets produce a pathway for the flow of electrical charges and provide a tougher hybrid system. The nanoscopic surface potential map reveals a higher work function of the individual functionalised SWNTs than surrounded GO sheets showing efficient charge exchange. We observed the enhanced conductivity up to 50 times and capacitance up to 3.5 times of the hybrid structure than the GO-paper. The laminate of polystyrene composites provided higher elastic modulus and mechanical strength when hybrid paper is used, thus paving the way for the exploitation of hybrid filler formulation in designing polymer composites.

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Synthesis and Characterization of Graphene Oxide/Chitosan Composite Aerogels with High Mechanical Performance

Polymers ◽

10.3390/polym11050777 ◽

2019 ◽

Vol 11 (5) ◽

pp. 777 ◽

Cited By ~ 7

Author(s):

Yang Gong ◽

Yingchun Yu ◽

Huixuan Kang ◽

Xiaohong Chen ◽

Hao Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Mechanical Performance ◽

X Ray Diffraction ◽

X Ray ◽

Composite Aerogels ◽

Mercury Porosimeter ◽

Chitosan Composite

Chitosan, a semi-crystalline biomolecule, has attracted wide attention due to its high synthesis flexibility. In this study, to improve the mechanical properties of chitosan aerogels (CSAs), graphene oxide (GO) was extracted and introduced into chitosan aerogels as fillers. The porous CSAs/GO composite aerogels were fabricated by an environmentally friendly freeze-drying process with different GO contents (0, 0.5, 1.0, 1.5, wt.%). The characteristics of the CSAs/GO were investigated by scanning electron microscopy (SEM), mechanical measurements and mercury porosimeter. The crystallinity of samples was characterized by X-ray diffraction (XRD). The mechanism of the effect of graphene oxide on chitosan was studied by Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The results show that the microstructure of the samples is developed in the network structure. The porosity of CSAs/GO aerogels is as high as 87.6%, and the tensile strength of the films increased from 6.60 MPa to 10.56 MPa with the recombination of graphene oxide. The crystallinity (CrI) of composite aerogels increased from 27% to 81%, which indicates that graphene oxide improves the mechanical properties of chitosan by chemical crosslinking.

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Fabrication of silane-grafted graphene oxide and its effect on the structural, thermal, mechanical, and hysteretic behavior of polyurethane

Scientific Reports ◽

10.1038/s41598-020-76153-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Joo Hyung Lee ◽

Seong Hun Kim

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Testing Machine ◽

Hysteretic Behavior ◽

Hexamethylene Diisocyanate ◽

Scanning Calorimetry ◽

Functionalized Graphene Oxide ◽

X Ray ◽

Ft Ir

Abstract Incorporation of nanofillers into polyurethane (PU) is a promising technique for enhancing its thermal and mechanical properties. Silane grafting has been used as a surface treatment for the functionalization of graphene oxide (GO) with numerous reactive sites dispersed on its basal plane and edge. In this study, amine-grafted GO was prepared using silanization of GO with (3-aminopropyl)triethoxysilane. The functionalized graphene oxide (fGO) was characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy. Next, it was introduced in PU fabricated using polycaprolactone diol, castor oil, and hexamethylene diisocyanate. The fGO–PU nanocomposites were in turn characterized by FT-IR, X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and a universal testing machine. The results obtained from these analyses showed changes in structural thermal properties, as well as improved thermal stability and mechanical properties because of the strong interfacial adhesion between the fGO and the PU matrix.

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Development of Trans-1,4-Polyisoprene Shape-Memory Polymer Composites Reinforced with Carbon Nanotubes Modified by Polydopamine

Polymers ◽

10.3390/polym14010110 ◽

2021 ◽

Vol 14 (1) ◽

pp. 110

Author(s):

Chuang Zhang ◽

Long Li ◽

Yuanhang Xin ◽

Jiaqi You ◽

Jing Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Thermal Stability ◽

Shape Memory ◽

Polymer Composites ◽

Photoelectron Spectroscopy ◽

Memory Performance ◽

Shape Memory Polymer ◽

Structure And Properties ◽

X Ray

In this study, which was inspired by mussel-biomimetic bonding research, carbon nanotubes (CNTs) were interfacially modified with polydopamine (PDA) to prepare a novel nano-filler (CNTs@PDA). The structure and properties of the CNTs@PDA were studied using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The CNTs and the CNTs@PDA were used as nanofillers and melt-blended into trans-1,4 polyisoprene (TPI) to create shape-memory polymer composites. The thermal stability, mechanical properties, and shape-memory properties of the TPI/CNTs and TPI/CNTs@PDA composites were systematically studied. The results demonstrate that these modifications enhanced the interfacial interaction, thermal stability, and mechanical properties of TPI/CNTs@PDA composites while maintaining shape-memory performance.

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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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Investigation of Carbon Nanotube Grafted Graphene Oxide Hybrid Aerogel for Polystyrene Composites with Reinforced Mechanical Performance

Polymers ◽

10.3390/polym13050735 ◽

2021 ◽

Vol 13 (5) ◽

pp. 735

Author(s):

Yanzeng Sun ◽

Hui Xu ◽

Zetian Zhao ◽

Lina Zhang ◽

Lichun Ma ◽

...

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Rational Design ◽

Large Scale ◽

Carbon Nanomaterials ◽

Mechanical Performance ◽

Polymer Matrix Composites ◽

Three Dimensional ◽

Scale Production

The rational design of carbon nanomaterials-reinforced polymer matrix composites based on the excellent properties of three-dimensional porous materials still remains a significant challenge. Herein, a novel approach is developed for preparing large-scale 3D carbon nanotubes (CNTs) and graphene oxide (GO) aerogel (GO-CNTA) by direct grafting of CNTs onto GO. Following this, styrene was backfilled into the prepared aerogel and polymerized in situ to form GO–CNTA/polystyrene (PS) nanocomposites. The results of X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy indicate the successful establishment of CNTs and GO-CNT and the excellent mechanical properties of the 3D frameworks using GO-CNT aerogel. The nanocomposite fabricated with around 1.0 wt% GO-CNT aerogel displayed excellent thermal conductivity of 0.127 W/m∙K and its mechanical properties were significantly enhanced compared with pristine PS, with its tensile, flexural, and compressive strengths increased by 9.01%, 46.8%, and 59.8%, respectively. This facile preparation method provides a new route for facilitating their large-scale production.

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Structure, Mechanical and Electrochemical Properties of Thermally Reduced Graphene Oxide-poly (Vinyl Alcohol) Foams

Periodica Polytechnica Chemical Engineering ◽

10.3311/ppch.11148 ◽

2017 ◽

Cited By ~ 1

Author(s):

Wenxiu Wang ◽

Hui Xu ◽

Jian Chen ◽

Yuanfang Shen ◽

Imre Bertóti ◽

...

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Vinyl Alcohol ◽

Lithium Ion ◽

Thermal Reduction ◽

Poly Vinyl Alcohol ◽

Structure Stability ◽

X Ray ◽

Wide Range

Graphene oxide foams with a wide range of poly (vinyl alcohol) contents were synthesized by freeze casting, and then thermally reduced at 300ºC in argon atmosphere. Their thermal stability, microstructure, composition and chemical states of constituents, mechanical and electrical properties were investigated by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, thermogravimetry, compressive testing and electrochemical analysis. The results indicated that the PVA content highly influenced the crystallinity and microstructure, resulting in different mechanical properties. After thermal reduction, not only graphene oxide was reduced to graphene, but also PVA was subjected to partial pyrolysis. With the increase of the PVA content, the intensity of the sp2 C-C bond decreased while the sp3 C-C bond increased. Although the mechanical properties decreased after thermal reduction, the composite foams still showed high cyclic structure stability up to 18 % compression strain. Meanwhile, the reduced foams exhibited high electrical conductivity. Applying as anodes in lithium ion battery, the initial discharge capacity for the foams can reach 1822 mA h g-1 and it remained more than 330 mA h g-1 after 50 cycles.

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Highly active carbon nanotube–promoted Rh-Mn-Li/SiO2 catalysts for the synthesis of C2+ oxygenates from syngas

Journal of Chemical Research ◽

10.1177/1747519820984728 ◽

2021 ◽

pp. 174751982098472

Author(s):

Jun Yu ◽

Ying Han ◽

Guoqing Chen ◽

Xiuzhen Xiao ◽

Haifang Mao ◽

...

Keyword(s):

Carbon Nanotubes ◽

Photoelectron Spectroscopy ◽

Co Hydrogenation ◽

X Ray ◽

Highly Active ◽

Transmission Electron ◽

Co Insertion ◽

Temperature Programmed Surface Reaction ◽

Temperature Programmed ◽

Oxygenate Synthesis

The effect of carbon nanotubes on the catalytic properties of Rh-Mn-Li/SiO2 catalysts was investigated for CO hydrogenation. The catalysts were comprehensively characterized by means of X-ray power diffraction, N2 sorption, transmission electron microscope, H2–temperature-programmed reduction, CO–temperature-programmed desorption, temperature-programmed surface reaction, and X-ray photoelectron spectroscopy. The results showed that an appropriate amount of carbon nanotubes can be attached to the surface of the SiO2 sphere and can improve the Rh dispersion. Moderate Rh-Mn interaction can be obtained by doping with the appropriate amount of carbon nanotubes, which promotes the formation of strongly adsorbed CO and facilitates the progress of CO insertion, resulting in the increase in the selectivity of C2+ oxygenate synthesis.

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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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Functional Bionanocomposite Fibers of Chitosan Filled with Cellulose Nanofibers Obtained by Gel Spinning

Polymers ◽

10.3390/polym13101563 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1563

Author(s):

Sofia Marquez-Bravo ◽

Ingo Doench ◽

Pamela Molina ◽

Flor Estefany Bentley ◽

Arnaud Kamdem Tamo ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Performance ◽

Cellulose Nanofibers ◽

Microstructural Characterization ◽

Fiber Formation ◽

Fiber Direction ◽

Composite Fibers ◽

X Ray Diffraction ◽

Gel Spinning ◽

X Ray

Extremely high mechanical performance spun bionanocomposite fibers of chitosan (CHI), and cellulose nanofibers (CNFs) were successfully achieved by gel spinning of CHI aqueous viscous formulations filled with CNFs. The microstructural characterization of the fibers by X-ray diffraction revealed the crystallization of the CHI polymer chains into anhydrous chitosan allomorph. The spinning process combining acidic–basic–neutralization–stretching–drying steps allowed obtaining CHI/CNF composite fibers of high crystallinity, with enhanced effect at incorporating the CNFs. Chitosan crystallization seems to be promoted by the presence of cellulose nanofibers, serving as nucleation sites for the growing of CHI crystals. Moreover, the preferential orientation of both CNFs and CHI crystals along the spun fiber direction was revealed in the two-dimensional X-ray diffraction patterns. By increasing the CNF amount up to the optimum concentration of 0.4 wt % in the viscous CHI/CNF collodion, Young’s modulus of the spun fibers significantly increased up to 8 GPa. Similarly, the stress at break and the yield stress drastically increased from 115 to 163 MPa, and from 67 to 119 MPa, respectively, by adding only 0.4 wt % of CNFs into a collodion solution containing 4 wt % of chitosan. The toughness of the CHI-based fibers thereby increased from 5 to 9 MJ.m−3. For higher CNFs contents like 0.5 wt %, the high mechanical performance of the CHI/CNF composite fibers was still observed, but with a slight worsening of the mechanical parameters, which may be related to a minor disruption of the CHI matrix hydrogel network constituting the collodion and gel fiber, as precursor state for the dry fiber formation. Finally, the rheological behavior observed for the different CHI/CNF viscous collodions and the obtained structural, thermal and mechanical properties results revealed an optimum matrix/filler compatibility and interface when adding 0.4 wt % of nanofibrillated cellulose (CNF) into 4 wt % CHI formulations, yielding functional bionanocomposite fibers of outstanding mechanical properties.

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