Synergistic Effect Of Graphene Oxide Research Articles

Magnetic poly(ionic liquid)/graphene oxide/Fe3O4 composites with multiple loss mechanisms for microwave absorbing

Microwave-absorbing materials are very important to reduce electromagnetic interference and pollution. Combining multi-component materials with multiple loss mechanisms is a practical strategy for enhancing microwave absorption performance. In this work, we synthesize a magnetic poly(ionic liquid) (PVim[FeCl4]) with crosslinkable groups and prepare PVim[FeCl4]/graphene oxide (GO)/Fe3O4 composites by incorporating GO and Fe3O4 to enhance the microwave absorption property of the composites. The synergistic effect of GO and Fe3O4 is studied at different feeding ratios, the PVim[FeCl4]/10%GO/20%Fe3O4 composite shows better microwave absorption performance, with a minimum reflection loss (RLmin) of −49.54 dB at 17.31 GHz and 7.1 mm thickness, along with an effective absorption bandwidth (EAB) of 2.52 GHz. This enhancement can be attributed to the quarter-wavelength matching model, well-matched characteristic impedance, and multiple loss mechanisms originating from PVim[FeCl4], GO, and Fe3O4. The magnetic poly(ionic liquid) composites show promising prospects in microwave absorbing materials.

Novel modification strategy via GO and polyurethane for epoxy nanocomposites: Simultaneous enhancements of fracture toughness and liquid oxygen compatibility for cryotank applications

Fracture toughness and liquid oxygen (LOX) compatibility of epoxy nanocomposites for liquid oxygen composite cryotank applications are two main concerns. In this work, a novel rigid-and-soft hybrid-microstructure modification strategy is proposed to improve these two properties simultaneously. Graphene oxide (GO) nanosheets are physically incorporated, and polyurethane (PU) particles are formed through phase-separation process. When 10 parts of PU and 0.1 parts of GO are added into 100 parts of epoxy (i.e., 10 phr PU and 0.1 phr GO), the fracture toughness is enhanced by 207.26 % at room temperature and 243.02 % at 90 K, respectively. Meanwhile, no sensitivity phenomena such as explosion, burning, flash, or charring for the nanocomposite are observed during liquid oxygen impact testing. Consequently, experimental characterizations and multiscale finite element models are utilized to reveal the synergistic effects of GO and PU on fracture behaviors and impact energy absorption.

Synergistic effects of graphene oxide and fly ash on rheology, mechanical properties, and microstructure of highly-flowable cementitious grouts

Due to their excellent mechanical strength and low pric, cementitious grouts have emerged as the popular for grouting applications. However, excessive use of cement results in significant energy consumption and associated carbon emissions, which is a concern from a sustainability perspective. In this study, inexpensive industrial waste fly ash (FA) was used to enhance the performance of graphene oxide (GO)-based cementitious grouts. The influence of varying dosages of GO and FA on the rheology, mechanical strength, durability, and microstructure development of cementitious pastes was investigated. The results show that adding FA to GO-based cementitious grouts improves the workability of the paste. The high-flowability cementitious grouts with combined GO and FA exhibit Bingham's fluid behavior, indicating that the synergistic effect of GO and FA does not alter the flow behavior of the paste. Further, the relationship between the rheological parameters of the modified paste and time was developed. For 0.03 wt% GO and 20 wt% FA incorporation, the flexural and compressive strengths of the paste at 28 days increased by 28.5% and 30.4%, respectively, compared to the blank group. The chloride ion penetration coefficient at 180 days was 1.007, indicating that FA could effectively replace a portion of the cement while enhancing the durability of the grout. Microstructural investigations confirmed that the synergistic effect of GO and FA does not generate new hydration products. GO accelerates the hydration reaction and activates the secondary pozzolanic effect of FA, forming more hydration products and thereby enhancing the mechanical strength and durability of the grout.

Rheological and Flexural Strength Characteristics of Cement Mixtures through the Synergistic Effects of Graphene Oxide and PVA Fibers.

This study investigates the synergistic effects of incorporating graphene oxide (GO) and polyvinyl alcohol (PVA) fibers into cement paste mixtures, aiming to modify their rheological properties and flexural behaviors with resistance to crack formation. The relationship between static yield stress and critical shear strain was examined in ten cement paste mixtures with varying concentrations of 6 mm and 12 mm PVA fibers and 0.05% GO. Additionally, viscosity analyses were performed. For the specimens fabricated from these mixtures, flexural strength tests were conducted using the Digital Image Correlation (DIC) technique for precise strain analysis under load history. The results indicated a significant increase in static yield stress, viscosity, and critical shear strain due to the combined addition of GO and PVA fibers, more so than when added individually. Notably, in PVA fiber-reinforced cement mixtures, the integration of GO increased the crack initiation load by up to 23% and enhanced pre-crack strain by 30 to 50%, demonstrating a notable delay in crack initiation and a reduction in crack propagation. Microstructural analyses using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) revealed a concentrated presence of GO around and on the PVA fibers. This promotes increased C-S-H gel formation, resulting in a denser microstructure. Additionally, GO effectively interacts with PVA fibers, enhancing the adherence of hydration products at their interface.

Synergistic effect of graphene oxide and coloidalnano-silica on the microstructure and strength properties of fly ash blended cement composites

Synergistic effect of graphene oxide and coloidalnano-silica on the microstructure and strength properties of fly ash blended cement composites

The ion diffusion-directed self-assembled graphene oxide coating and its synergistic lubrication mechanism against environmental moisture

Graphene oxide (GO) is a layered lubricant with high performance, but its application is limited by complex synthesis and relatively low resistance to environmental moisture. In this study, a simple and versatile self-assembly method was developed to prepare GO coatings with thicknesses ranging from the nanometer to micrometer scale. The results indicate that tribological performance is significantly influenced by ambient humidity. During friction, water molecules tend to form hydrogen bonds with oxygen functional groups and defects on GO nanosheets, destroying the ordered layer structure and thus degrading tribological performance. In addition, the further incorporation of lubricating oil is beneficial for achieving lower friction attributed to the synergistic effect of GO coating and oil film that serves as a moisture repellent.

Synergistic effect of graphene oxide and partially hydrolyzed polyacrylamide for enhanced oil recovery: Merging coreflood experimental and CFD modeling approaches

The present study provides a comprehensive examination of GO-HPAM polymeric nanocomposite, contributing significantly to enhanced oil recovery (EOR). At the core of this investigation are a series of experimental tests and validations of simulations. The study examines the bonding effects, structural integrity, morphological interconnections, and stability of the GO-HPAM. The significance of reservoir and in-situ fluid conditions in the effort to improve EOR The GO-HPAM stabilization composite was developed, assessed, and examined for its extended core-flooding capabilities owing to its high energy characteristics. The simulation model was built on a Cartesian grid with fixed values for the bulk volume, injection rate, well completion, and rock-fluid properties using ANSYS Fluent. During the flooding experiment, the injections of 2 PV of brine, 0.50 PV of GO-HPAM, and 2 PV of chase water were precursors. The findings showed that 19.67% of the original oil could be recovered after injecting the nanocomposite fluid consisting of GO-HPAM. The GO-HPAM flooding gathered over 60% more oil than the traditional EOR polymer. Moreover, numerical modeling demonstrated a performance of the GO-HPAM combination comparable to the experimental results. The proposed synergetic fluid will assist researchers and industrialists in the design of an EOR process.

Polyvinyl Alcohol/Graphene Oxide Nanocomposite Membrane for Highly Efficient Oil/Water Mixture Separation

The growing amount of oily wastewater caused by frequent oil spill accidents poses a severe threat to the ecological environment. Therefore, the development of highly efficient oil/water separation methods is highly necessary. This work reports the preparation of a nanocomposite membrane using graphene oxide (GO)/polyvinyl alcohol (PVA) coated on steel meshes for oil/water mixture separation. PVA firmly anchors GO nanosheets onto the mesh surface through strong hydrogen bonds using glutaraldehyde (GA) as a crosslinker. This nanocomposite membrane exhibited superhydrophilic and underwater superoleophobic properties, with the highest oil contact angle of 158º due to its highly rough structure. The synergistic effects of GO and PVA further improved the superhydrophilicity of the prepared membrane, due to the hydrophilic nature of both GO and PVA. The separation efficiencies and water flux for a variety of oil/water mixtures were above 97.8% and 6000.0 L m−2 h−1, respectively. The prepared membrane showed excellent chemical resistance under harsh conditions without evident change in its surface wettability. Moreover, its underwater superoleophobicity was maintained after 10 cycles of abrasion testing.

A novel proton exchange membrane with long-range ordered proton transport pathways through modulation of interfacial interactions via amino-functionalized polyhedral oligomeric silsesquioxane-grafted graphene oxide

Nano octa-aminopropyl polyhedral oligomeric silsesquioxane (OA-POSS) was grafted into graphene oxide (GO) via covalent bonding to synthesize OA-POSS-g-GO. A novel SP/OA-POSS-g-GO proton exchange membrane was prepared by adding sulfonated poly (ether ether ketone) (SPEEK, SP). OA-POSS was well dispersed on GO to form an ordered acid-base pair with SPEEK, which facilitated the construction of continuous ion channels. GO as a carrier facilitated the construction of long-range proton conduction pathways in the membrane. The strong interactions between OA-POSS and SPEEK along with the synergistic effect of GO modulate the size of ionic clusters and increased the bound water ratio within the membrane. The conductivity of the SP/OA-POSS-g-GO-2 membrane (80 °C, 95% RH) reached 0.2096 S⋅cm−1, which was 1.7 times higher than that of the SPEEK membrane (0.1265 S⋅cm−1). The conductivity of the SP/OA-POSS-g-GO-2 membrane increased at 100 °C and 40% RH, while that of the SPEEK membrane decreased with the temperature increased above 80 °C. The maximum power density of the single cell assembled from the composite membrane reached 305.8 mW⋅cm−2 at 80 °C and 95% RH, which was 1.4 and 1.3 times higher than that of the SPEEK and Nafion 117 membrane, respectively.

Facile synthesis of a GO-g-C3N4/BaTiO3 ternary nanocomposites for visible-light-driven photocatalytic degradation of rhodamine B

Photogenerated charge carriers can undergo rapid recombination in conventional photocatalyst systems, reducing their photocatalytic efficiency. To address this bottleneck, a g-C3N4/BaTiO3 (CNB) heterojunction composite was decorated with different mass ratios of graphene oxide (GO) to form a novel visible-light responsive ternary GO-g-C3N4/BaTiO3 (GOCNB) nanocomposite using a facile fabrication method. The GOCNB photocatalyst exhibited significantly higher light absorption and greater charge transfer than CNB, g-C3N4, or BaTiO3. The photodegradation performance of GOCNB was optimized with a 2% mass loading of GO, and it achieved a degradation rate constant of 14.9 × 10−3 min−1 for rhodamine B with an efficiency of 94% within 180 min. The rate constant was 8-fold and 6-fold higher than that of bare BaTiO3 and CNB, respectively. The stronger photocatalytic activity was attributed to the synergistic effect of GO, g-C3N4, and BaTiO3, with g-C3N4 and BaTiO3 promoting charge transfer within a wider visible light range and GO promoting electron mobility and the photocatalyst's adsorption capacity. In particular, the proposed system maintained the spatial separation of photogenerated electron–hole pairs, which is vital for high photocatalytic activity. This study provides new insights into semiconductor-based photocatalytic systems and suggests a route for more environmentally sustainable technologies.

Synergistic effect of graphene oxide based nitrogen-doped nano-titanium oxide for effective adsorption and photo catalysis of dibutyl phthalate and organic pollutants from water

Synergistic effect of graphene oxide based nitrogen-doped nano-titanium oxide for effective adsorption and photo catalysis of dibutyl phthalate and organic pollutants from water

Comparative analysis of the synergistic effects of hybrid nanomaterial reinforcement in cementitious Composites: A perspective for pore refinement and thermal resistance

This study aimed to reveal the synergistic effects of graphene oxide (GO)/nanosilica (NS)/functionalized carbon nanotube (FCNT) hybrid nanomaterials on the thermal resistance and pore refinement of cementitious composites. The dispersion states and sizes of the nanomaterials in distilled water and Ca2+-rich solutions were assessed. In addition, the pore characteristics and thermal resistance of the nanomaterial-incorporated cementitious composites were analyzed. In the GO/NS/FCNT hybrid solution, a reinforcing effect of FCNT on the GO plate resulted in high resistance to wrinkling and agglomeration of GO; therefore, the stretched GO plate structure was advantageous for long-term dispersion maintenance, and well-dispersed NS enabled a more active pozzolanic reaction in cement paste. As a result, the triple-hybrid GO/NS/FCNT-reinforced cementitious composites demonstrated improved thermal resistance owing to their high residual strength after heating as well as homogenized pore structures with less elongated pore shapes and lower porosity than control specimens without nanomaterials.

Synergistic effect of graphene oxide and cathodic protection to enhance the long-term protective performance of organic coatings

Synergistic effect of graphene oxide and cathodic protection to enhance the long-term protective performance of organic coatings

A novel combination of graphene oxide/palladium integrated polycaprolactone nanocomposite for biomedical applications

To design a multi-biofunctional polymeric nanocomposite for therapeutic applications, biocompatible graphene oxide-palladium (GO-Pd) nanostructures were incorporated into a polycaprolactone (PCL) system. Metallic palladium nanoparticles were anchored over the graphene system through simple electrostatic interaction without reducing graphene oxide (GO). The XPS, XRD, SEM, TEM, EDAX, FTIR, and Raman spectral analysis divulged that the nanohybrid system consists of graphene layers embedded with spherically shaped palladium nanoparticles (PdNPs). Additionally, the optical characteristics of the hybrid system illustrate the surface plasmon resonance offered by metallic PdNPs on graphene. The hemocompatibility test corroborates the compatibility of nanostructures with biological systems. Multifunctional polymeric nanocomposites were obtained by integrating the GO-Pd nanoparticulate system into the PCL matrix. The PCL-GO-Pd nanocomposite was identified to be biodegradable and mechanically stable with enhanced surface wettability. Additionally, PCL-GO-Pd nanocomposite demonstrated distinguished bactericidal activity towards both S. aureus and E. coli due to the synergistic effect of GO and PdNPs, via oxidative stress and cell membrane disruption. Moreover, the hybrid nanocomposite showed remarkable antibacterial efficacy, biomineralization, and cell viability, affirming its bioactive behavior. Therefore, the current research introduces a biocompatible polymeric nanocomposite with considerable biological performance for various therapeutic applications, particularly for bone tissue regeneration.

Cytotoxicity and biocompatibility of Meropenem-loaded graphene oxide and its antibacterial effects against carbapenem-resistant Gram-negative bacteria

The rising prevalence of multidrug-resistant (MDR) bacteria, mainly Gram-negative bacteria, challenges their effective treatment. Graphene oxide (GO) represents antibacterial activities; however, the synergistic effect of GO with conventional antibiotics remains unclarified. Here, meropenem-loaded GO (Mrp-GO) was prepared and its physicochemical and biocompatibility properties along with its inhibitory effect against carbapenem-resistant Gram-negative bacteria were evaluated. Cytotoxicity of Mrp-GO on human bone marrow-derived mesenchymal stem cells (hBM-MSCs) was examined as well. The prepared nanoparticles had suitable and acceptable physicochemical properties. The antibacterial activity of Mrp-GO increased in comparison to the GO and Mrp alone. Moreover, the Mrp-GO had low hemolytic effects at the concentrations required for bacterial inhibition. The cell viability of hBM-MSCs at toxic Mrp-GO concentrations for bacterial isolates was almost 90–100%. The combination of nanostructure and conventional antibiotics can be a promising treatment modality against carbapenem-resistant Gram-negative bacteria.

Manipulation of mechanical and thermal properties of graphene oxide/nanoclay/unsaturated polyester hybrid nanocomposites by the surface chemistry and nanofiller composition

Dispersion of platelet-like nanominerals in low-viscous resins is a serious challenge; which arises from the strong interactions among the large surface area of the layers. Herein, we improved the dispersion of graphene oxide (GO) within unsaturated polyester (UP) resin and synergistically enhanced the mechanical and thermal properties of the resulting nanocomposites. In a multi-stage manner, GO was incorporated into a novel hybrid structure before adding to the polymer matrix alongside with benefited from the advantage of surface functionalization. Functional hybrid nanofiller skeletons comprising GO and nanoclay (NC) were designed and prepared at different composition ratios (25:75, 50:50 and 75:25) and different surface chemistries via modification with two thermal-resistant silane coupling agents, namely (3-Aminopropyl) triethoxysilane (APTES) and 3-(trimethoxysilyl) propyl methacrylate (MPS). The optimal loading of different hybrid structures into UP has been examined by applying three loading levels (0.25, 0.50 and 1.00 wt%). The results indicated the synergistic effects of GO and NC on the mechanical properties of UP, where the composition ratio of the hybrid constituents played a key role. Moreover, it was demonstrated that the range of composition ratio for the realization of synergistic reinforcement is strongly affected by the surface chemistry of the GO and NC. For UP matrix reinforced with APTES-modified hybrid nanofillers of GD:CD at 50:50 w/w composition, a higher tensile modulus compared to blank UP (≈+21.5%) was obtained due to boosted dispersion of nanoplatelets in UP matrix. The results of DMTA and TGA analyses suggested that there are two different UP/GO and UP/NC interfacial interactions in the composites containing unmodified hybrid nanofillers. However, after modification of hybrid nanofillers, the homogeneous dispersion of nanoplatelets boosted the interfacial interactions between nanofillers and polymer, such that higher properties were obtained.

Fabrication of graphene oxide/copper synergistic antibacterial coating for medical titanium substrate

Titanium (Ti) was an excellent medical metal material, but the lack of good antibacterial activity confined its further practical application. To solve this dilemma, a coating containing graphene oxide (GO) and copper (Cu) was prepared on the surface of Ti sheet (Ti/APS/GO/Cu). First, physical sterilization could be carried out through the sharp-edged sheet structure of GO. Second, the oxygen-containing functional group on the surface of GO and the released Cu2+ would generate reactive oxygen species for chemical sterilization. The synergistic effect of GO and Cu substantially enhanced the in vitro and in vivo antibacterial property of Ti sheet, thereby reducing bacterial-related inflammation. Quantitatively, the antibacterial rate of Ti/APS/GO/Cu against E. coli or S. aureus reached over 99%. Besides, Ti/APS/GO/Cu showed excellent biocompatibility and no toxicity to cell. Such work developed multiple sterilization avenues to design non-antibiotic, safe and efficient antibacterial implant material for the biomedical domain.

Efficacious Removal of Flonicamid Insecticide from Water by GO@functionalized Calix[4]pyrrole: Synergistic Effect in Adsorption

AbstractThe presence of a highly toxic pyridine carboxamide insecticide, namely flonicamid in water bodies poses a serious risk to both the aquatic ecosystem and human health. Therefore, a graphene oxide (GO) decorated with azo‐functionalized calix[4]pyrrole i. e. GO‐azocalix[4]pyrrole (GACP) was synthesized to study the removal of flonicamid insecticide through adsorption. The nano‐adsorbent was characterized by IR, XPS, TGA, Raman, SEM, and TEM data. The effect of concentration of flonicamid solution, contact time, adsorbent dosage, temperature, and pH was investigated in the batch adsorption process. Experimental data suggested that equilibrium was attained within 40 min and adsorption efficiency was 93.28 %. The synergistic effect of GO and azocalix[4]pyrrole played an important role in the adsorption. The Langmuir isotherm was followed and the maximum adsorption capacity was found to be 11.43 mg/g. The pseudo‐second‐order kinetic data was well obeyed and thermodynamic investigation suggested the feasible and spontaneous nature of flonicamid onto GACP nanocomposite.

Synergistic effect of graphene oxide on structural and electrical performance of PEDOT:PSS polymer

Synergistic effect of graphene oxide on structural and electrical performance of PEDOT:PSS polymer

Graphene oxide/methyl anthranilate modified anti-biofouling membrane possesses dual functions of anti-adhesion and quorum quenching

Biofouling has always been a persistent problem impeding the applications of membranes in water treatment. Quorum sensing (QS) inhibitors are able to interfere with bacterial cell-to-cell communication to alleviate membrane biofouling, among which, methyl anthranilate (MA) aims at disrupting the Pseudomonas quinolone signal (PQS)-mediated QS system to inhibit biofilm formation. In this study, we developed a novel anti-biofouling membrane via immobilizing MA on graphene oxide (GO) nanocarrier, which was then successfully coated onto a polyvinylidene fluoride (PVDF) membrane through layer-by-layer assembly method. The introduction of QS inhibitor MA suppressed the expression of PQS synthesis gene pqsABCDE, N-acyl homoserine lactones (AHL) synthesis gene lasI, rhamnolipid synthesis gene rhlA and PQS receptor gene pqsR, thereby mitigating biofilm formation on the modified membrane. GO on membrane surface contributed to the reduction of bacterial initial adhesion. The synergistic effect of GO and MA endowed the modified membrane with dual resistance to biofouling. Compared with the virgin membrane, the extracellular polymeric substances (EPS), ATP and total cell fluorescence on GO/MA-PVDF membrane (GO:MA = 1:3, 5 layers) were substantially reduced by 50%, 73% and 86%, respectively, illustrating its excellent anti-biofouling capability. Notably, the incorporation of GO/MA was still efficient when treating real secondary effluent, with the evidence of lower flux decline and restrained biofilm formation. Taken together, we believe that GO/MA-PVDF membrane with both anti-adhesion and anti-biofilm capability has broad prospects for biofouling control in water treatment.