Graphene Oxide Content Research Articles

Layered double hydroxide (LDH)-derived zinc oxide (ZnO) nanorod on exfoliated graphene oxide (GO) nanosheet for photocatalytic dye degradation and hexavalent chromium reduction

A new low-temperature facile chemical decomposition of layered double hydroxide (LDH) has been developed for the large-scale controlled synthesis of zinc oxide (ZnO) nanorod on exfoliated graphene oxide (GO) nanosheet. ZnAl-LDH/GO composite precursor was prepared via in situ growth of the LDH on the exfoliated GO nanosheets. Thermo-chemical decomposition of ZnAl-LDH/GO composite at 80 °C produced highly dispersed ZnO nanorods on GO nanosheets. Although, neat ZnAl-LDH produces ZnO nanoparticle aggregates in the absence of GO. The morphology and properties of ZnO nanorods/GO nanocomposite was studied by X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The band gap engineering of the nanocomposite was evaluated by varying GO content. The ZnO/GO nanocomposites materials exhibited excellent photo-catalytic activity towards the degradation of methylene blue (MB) and Cr(VI) reduction under the irradiation of direct sunlight at ambient condition. GO plays a crucial role in the directional growth of nanorods and enhances the photocatalytic activity of ZnO nanorods via the synergistic hole formation and electron transfer effect for the potential remediation of waste water.

3D Bioprinting of Biomimetic Alginate/Gelatin/Chondroitin Sulfate Hydrogel Nanocomposites for Intrinsically Chondrogenic Differentiation of Human Mesenchymal Stem Cells.

3D-printed hydrogel scaffolds biomimicking the extracellular matrix (ECM) are key in cartilage tissue engineering as they can enhance the chondrogenic differentiation of mesenchymal stem cells (MSCs) through the presence of active nanoparticles such as graphene oxide (GO). Here, biomimetic hydrogels were developed by cross-linking alginate, gelatin, and chondroitin sulfate biopolymers in the presence of GO as a bioactive filler, with excellent processability for developing bioactive 3D printed scaffolds and for the bioprinting process. A novel bioink based on our hydrogel with embedded human MSCs presented a cell survival rate near 100% after the 3D bioprinting process. The effects of processing and filler concentration on cell differentiation were further quantitatively evaluated. The nanocomposited hydrogels render high MSC proliferation and viability, exhibiting intrinsic chondroinductive capacity without any exogenous factor when used to print scaffolds or bioprint constructs. The bioactivity depended on the GO concentration, with the best performance at 0.1 mg mL-1. These results were explained by the rational combination of the three biopolymers, with GO nanoparticles having carboxylate and sulfate groups in their structures, therefore, biomimicking the highly negatively charged ECM of cartilage. The bioactivity of this biomaterial and its good processability for 3D printing scaffolds and 3D bioprinting techniques open up a new approach to developing novel biomimetic materials for cartilage repair.

Graphene oxide nanocellulose composite as a highly efficient substrate-free room temperature gas sensor

This study introduces the development of novel, flexible gas sensors operating at room temperature (RT), utilizing a graphene oxide (GO) via the modified Hummers' method and bacterial nanocellulose (BNC) composite to enhance gas detection in industrial and environmental settings. The composite materials, denoted as GO@BNC, were synthesized with varying GO concentrations ranging from 2 % to 30 %, aiming to investigate their responsiveness to gases such as carbon dioxide (CO2), oxygen (O2), acetone (Ac), and ethanol (Eth). The prepared nanomaterials were characterized using FT-IR, Raman, TGA, SEM, and AFM techniques. The bandgap of Go ranges from 4.19, 3.47, 3.16, 2.79, and 2.48 eV for 2, 5, 10, 20, and 30 % GO concentrations, respectively. Notably, the sensor containing wt % of 20 % GO concentration exhibited remarkable sensitivity to Ac, achieving a 270 % increase in resistance at a concentration of 250 μL/L. Conversely, the sensor with a wt % of 30 % GO composition showed superior sensitivity to Eth, with a 420 % signal enhancement under similar conditions. Further modification of GO@BNC through mild reduction resulted in the formation of reduced graphene oxide (rGO@BNC) composites intended to assess the functional groups' impact on sensing performance. Our findings underscore the potential of GO@BNC composites as sustainable and efficient materials for fabricating eco-friendly flexible gas sensors and devices for detecting organic compounds.

Physiological and transcriptomic responses of silkworms to graphene oxide exposure

The growing use of nanomaterials has sparked significant interest in assessing the insect toxicities of nanoparticles. The silkworm, as an economically important insect, serves as a promising model for studying how insects respond to harmful substances. Here, we conducted a comprehensive investigation on the impact of graphene oxide (GO) on silkworms using a combination of physiological and transcriptome analyses. GO can enter the midguts and posterior silk glands of silkworms. High GO concentrations (> 25 mg/L) significantly (P < 0.01) inhibited larval growth. Additionally, GO (> 5 mg/L) significantly reduced the cocooning rate, and GO (> 15 mg/L) hindered oviduct development and egg laying in silkworms. GO increased the reactive oxygen species content and regulated catalase activity, suggesting that it may affect insect growth by regulating reactive oxygen detoxification. The transcriptome data analysis showed that 35 metabolism-related genes and 20 ribosome biogenesis-related genes were differentially expressed in response to GO, and their expression levels were highly correlated. Finally, we propose that a Ribosome biogenesis–Metabolic signaling network is involved in responses to GO. The research provides a new perspective on the molecular responses of insects to GO.

Preparation and Properties of Environmentally Friendly, Hydrophobic, Corrosion-Resistant, Multifunctional Composite Coatings

With the continuous exploitation of the marine resources, the equipment should meet the marine complex working environment. In this study, a type of environmentally friendly coating was prepared. Based on low surface energy environmental protection and anti-fouling, a film forming material with water-based epoxy-modified silicone resin emulsion was prepared. And industrial fillers were added to give it both inorganic and organic properties. Meanwhile, various contents of graphene oxide (GO) were added in the coating system. The coating properties were comprehensively analyzed, and the optimal GO content was obtained as 0.1 wt. %. The composite coating was studied by seawater immersion experiments, and the failure process of the coating in was proposed. The composite coating prepared in the present study has both environmental protection and hydrophobic anti-fouling characteristics, and its comprehensive performance is excellent through various performance evaluations, i.e., it meets the requirements of long-term coating, environmental friendliness and anti-fouling and corrosion resistance.

Exfoliation of Graphite into Graphene Oxide and Reduction by Plant Extract to Synthesize Graphene

Graphene oxide (GO) is a demand material in industrial field for many applications such as electronic devices, capacitor and sensor. This is due to its unique structures and excellent properties. The GO sheets were exfoliated from graphite rod in electrochemical exfoliation. To reduce GO, an electrochemical reduction of GO using green tea was carried out in this research. The conventional chemical reduction method consumed highly toxic and strongly hazardous chemicals such as hydrazine to reduce GO to reduced GO (RGO). Therefore, a green synthesis method was proposed by using green tea leaves extract as the reducing agent to synthesize RGO. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) results show that low amount of oxygen-containing functional groups was remained after green tea reduction due to weak reduction capability by green tea. In addition, EDX indicates that oxygen content of GO was decreased from 23.23 to 16.89 Mass% after green tea reduction.

A physicochemically reformed nanostructured graphene oxide-doped indium magnesium oxide film with enhanced electrical properties

Brush-coated graphene oxide (GO)-doped indium magnesium oxide (InMgO) films were produced in this study. The GO concentration was adjusted to 0, 5, and 15 wt%. The hybrid films were constructed using a one-step facile brush-coating process. The formed hybrid film had an oriented anisotropic morphology with a micro/nanogroove structure due to the shear stress induced by the brush hair movement. This anisotropic structure was used as a liquid crystal (LC) alignment layer. Polarized optical microscopy and pretilt angle analysis revealed the presence of a uniform and homogeneous LC alignment on the hybrid film. The film exhibited excellent light control with the LCs, as well as stable and high optical transmittance in the visible region. The GO doping of InMgO increased its polar anchoring energy and decreased its hysteresis characteristics for LC electronic device applications. These results demonstrate the potential of doping metal oxide films with GO and brush coating them for use in next-generation LC devices.

Evaluation of the mechanical properties and degradation behavior of chitosan-PVA-graphene oxide nanocomposite scaffolds in vitro

ObjectivesChitosan (CTS) has been a popular option for scaffold fabrication because of its biocompatibility, biodegradability, antimicrobial and nonimmunogenic effects. However, it is of limited function, due to its low mechanical strength and its solubility in acidified media. These limitations could be overcome by its blending with PVA and incorporation with bioactive materials to improve its mechanical properties and tissue regeneration capability. MethodsCarbon based nanomaterials, such as graphene oxide (GO) incorporated with CTS/PVA blend to improve composite-scaffold stability. GO nanoparticles were chemically prepared and fully characterized. Different concentrations of both CTS and nano-GO were used for the fabrication of CTS/PVA/GO nanocomposite films through the solvent-casting method. The mechanical properties, thermal stability biodegradation, and swelling of the nanocomposite films were evaluated after characterization by XRD, FTIR and SEM, to detect the effect of GO incorporation in the scaffold to select the suitable dental application. ResultsA better performance was observed in thermal stability, biodegradation, and water resistance after GO addition into CTS/PVA scaffolds. Regarding mechanical properties, groups were assessed by Kruskal Wallis test afterward Dunn’s post hoc test. There was no significant difference in tensile strength between the nanocomposite films of CTS (2%) and CTS (3%). The tensile strength decreased after addition of nano-GO at different concentrations. The elastic modulus significantly increased when (1%) GO was added into the 1CTS (2%):1PVA. ConclusionsCTS/PVA/GO nanocomposite can be used in dental hard tissue engineering, as the incorporation of GO into the CTS/PVA polymer blend improves its properties which is regarded as the critical concentrations of CTS and GO.

The effect of reduced graphene oxide concentration on the wear behaviour of reduced graphene oxide–nickel–boron (Ni–B–rGO) electroless coatings

In this article, the electroless nickel-boron coatings containing different rGO concentrations (0,6, 20.5, 35 and 40 mg/L) were deposited on AISI 4140 steel. Their structural properties were examined using X-ray diffraction, Raman spectroscopy, infrared spectroscopy, scanning electron microscopy and hardness analysis. Moreover, their friction coefficient and wear properties were studied using a pin-on-disc test. The results showed that as the rGO concentration increased, the structure of the coating changed from amorphous to semi-crystalline. Adding rGO up to 20.5 mg/L increased the hardness of the as-plated NiB coating from 519 to 863 Hv and reduced its specific wear rate from 1.28 × 10−9 to 0.68 × 10−9 kg/Nm. However, increasing the rGO concentration to 40 mg/L led to rGO agglomeration and increased the specific wear rate of the coating.

Graphene/graphene oxide and melamine as synergistic additives for polyester nanocomposite coatings

Ensuring mechanical robustness is crucial for polyester coatings on pre-coated metal (PCM). The incorporation of nanofillers such as graphene nanoplatelets (GNP) and graphene oxide (GO) has demonstrated potential in enhancing mechanical properties of polymeric nanocomposites. However, the utilisation of these nanofillers in saturated polyester systems remains largely unexplored. Therefore, this study developed polyester-based nanocomposite coatings incorporating GNP or GO and systematically investigated the effects of the nanofiller loading and the hexa (methoxymethyl)melamine (HMMM)/polyester ratio on the properties of the coatings. Adding nanofillers led to the reduction of both glass transition temperature (Tg) and hardness (H) of the coating. Specifically, at a 1:5 HMMM/polyester ratio, Tg reduced from 29.9 °C for plain polyester (Blank) to 26.1 °C and 22.0 °C for polyesters with 5 wt% GNP (A-5.0GNP) and GO (A-5.0GO) respectively; H values also decreased from 274 MPa for Blank polyester to 222 MPa and 143 MPa for A-5.0GNP and A-5.0GO, respectively. The hydroxyl groups on the nanofillers affected crosslinking between HMMM and polyester by reacting with HMMM, thereby reducing the crosslink density of the cured coatings. Increasing nanofiller loading led to a more significant reduction in crosslink density, resulting in decreased Tg and H values. At the same loading level, the significantly higher hydroxyl content of GO had a more pronounced effect in reducing crosslink density compared to GNP. Furthermore, an increase in HMMM compensated for the HMMM loss to GO and facilitated the polyester crosslinking reactions, leading to significant increase in both Tg and H. Specifically, for the 2 wt% GO nanocomposites, Tg increased significantly from 24.7 °C to 32.1 °C with a rise in the HMMM/polyester ratio from 1:5 to 1:2, while the H value increased notably from 193 MPa to 452 MPa.

Synthesis of BaAl2Ge2O8 by the Pechini method, using graphene oxide as stabilizing agent

In this study, BaAl2Ge2O8 (BAG) synthesis was performed using the Pechini method for the first time. Graphene oxide (GO), used as a precursor agent to obtain the pure phase of BAG, was incorporated to the precursor powders before heath treatment at 1300 °C. The pure BAG phase was obtained with a cation:citric acid molar ratio of 8:1, a pH = 8, and a mass concentration of GO from 0.5 wt%. The incorporation of 2 wt% of GO promoted the formation of irregular-shaped BAG flakes with a size smaller than 3 µm. The pure BAG phase exhibited a band gap of 5.12 eV.

Preparation and separation performance of biomimetic polycaprolactone/graphene oxide composite membrane

The treatment of oil and water pollutants generated in industrial production and daily life is an urgent issue that needs to be addressed globally. Inspired by superhydrophobic self-cleaning lotus leaves, durable and sturdy superhydrophobic water-filled barriers, and lightweight bird bones with hollow structures, researchers can obtain superhydrophobic surfaces by creating rough surfaces of layered micro- and nanostructures. In this study, hydrophobic polycaprolactone (PCL) membranes with layered structures were prepared by electrospinning. The surface roughness of the PCL membrane was improved by compounding graphene oxide (GO) functional components on the PCL membrane surface, thereby enhancing its hydrophobicity. The infrared spectrum of the PCL/GO membrane shows that PCL and GO are physically mixed, and no chemical changes occur during the electrospinning process. Scanning electron microscopy (SEM) images of the composite fibre membranes reveal the interconnections between fibres. Fourier transform infrared spectroscopy (FTIR) provides information on the chemical components of the membranes. Thermogravimetric analysis (TGA) was employed to assess the thermal stability of the membranes. The oil-water separation test demonstrated that the PCL/GO membrane exhibited a separation efficiency of 99.94% for hexane-water mixtures. In the oil adsorption test, the maximum adsorption capacity of the membrane for n-hexane was 35.8 g/g. In the contact angle measurement experiment, the water contact angle of the nanofiber membrane increased from 120.12° to 140.15° with increasing GO content, indicating that the composite membrane exhibited enhanced hydrophobicity.

Multi-layer shearing induced high orientation of graphene oxide sheets towards high-performance macrostructures

The orientation of graphene nanosheets in microstructures is directly related to the mechanical properties and thermal conductivity of graphene-based macrostructures. However, efficient and scalable modulation of the orientation of 2D graphene nanosheets remains challenging. Herein, a simple and effective approach was proposed by introducing a multi-layer shearing field in thick graphene oxide (GO) gel coatings to improve the total orientation of GO films. Hydrodynamic simulations were performed via the lattice-Boltzmann method to reveal the microscale mechanism of the flow profile in improving the orientation of GO nanosheets. The result was experimentally verified by fast Fourier transform (FFT) of the cross-section scanning electron microscope (SEM) images of freeze-dried GO films and wide-angle X-ray scattering (WAXS) patterns of 16 various samples under different shearing line distances, velocities, and GO concentrations. The obtained GO films exhibit high orientation (Herman's orientation factor ƒ = 0.922), high strength (419.2 MPa), and high modulus (26.2 GPa), respectively, which are 1.06, 5.57, and 3.49 times higher compared to GO films prepared through the frequently used doctor blade method. The good orientation of GO is remained and further improved to the ultra-high orientation (ƒ = 0.968) after being graphitized at 3150 °C and roll pressing, and the oriented thick graphene films achieved the highest thermal conductivity (1629 W m−1 K−1 for 86 μm and 1593 W m−1 K−1 for 110 μm) compared to other graphene films mentioned in the literature as having a similar thickness. The multi-layered shearing strategy represents a facile technology for assembling two-dimensional (2D) nanoscale building blocks into a macroscopic structure with good orientation and high performance.

The effect of graphene oxide content on the photocatalytic activity of (ZnCdS/MnFe2O4/GO) nanocomposite

Novel ternary Zinc cadmium sulfate/Manganese ferrite/Graphene oxide (ZnCdS/MnFe2O4/GO) nanocomposites were synthesized via a hydrothermal process in this study, with a focus on optimizing the graphene oxide (GO) content. Characterization techniques such as X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), UV–visible spectroscopy, photoluminescence (PL) spectroscopy, and N2 physisorption were employed. The investigation revealed that nanocomposites with 3 wt% GO content exhibited superior adsorption capacity and visible-light photocatalytic activity for the removal of Methylene blue (MB) from wastewater. The ZnCdS/MnFe2O4/GO 3 % composite demonstrated exceptional stability and efficiency, achieving nearly 96 % MB removal within 220 min. Moreover, the ZnCdS/MnFe2O4/GO 3 % nanocomposites displayed promising reusability with sustained photocatalytic activity over multiple degradation-regeneration cycles. These findings highlight the potential of ternary GO/ZnCdS/MnFe2O4 nanocomposites as effective photocatalysts for the practical remediation of organic pollutants in wastewater systems.

Covalently assembling multi-dimensional carbon-based nanoclay composites via ionic liquid linkers into PVA membrane for molecular separation

The application of membrane-based separation technology in purifying azeotropic solutions plays a crucial role in minimizing energy consumption during reactive distillation. The strategic integration of multi-dimensional structural composites within mixed matrix membranes (MMMs), characterized by a robust framework and efficient molecular transport channels, poses challenges but demonstrates significant potential for advancing the development of high-performance membrane fabrication. Herein, we proposed a novel strategy to covalently assemble halloysite nanotubes (HNTs) and graphene oxide (GO) using ionic liquids (ILs) as linkers. When incorporated into the polyvinyl alcohol (PVA) matrix, the ILs@HNTs@GO (IHGO) composites exhibit excellent interfacial compatibility, and ILs also enhanced the composite’s selective transfer ability to water molecules. The optimal separation performance for pervaporation dehydration from a ternary solution was respectively 2.57 (selectivity) and 1.74 (permeability) times higher than those of the pristine PVA membrane. The structural stability of the MMMs and their separation mechanism has been comprehensively validated by adjusting the content of GO in IHGO composites and conducting simulations. This study holds significant theoretical and practical implications for organic compounds purification, while simultaneously paving new avenues for the fabrication of structurally robust and high-performance MMMs with optimal filler effectiveness.

The absorption effect and mechanism of graphene oxide removal from aqueous solution by basalt stone power

Graphene oxide (GO) is a novel carbon material utilized extensively for diverse industrial applications. When exposed to environmental elements like sunlight and chlorination, GO can undergo a series of physical and chemical transformations, and its presence in water and the environment can endanger ecosystems. Therefore there is a need for methods that can effectively remove GO from water. Accordingly, we delve into the efficacy of basalt stone powder (BSP) as an adsorption medium for purifying aqueous solutions of GO. We examine the impact of various experimental parameters—namely pH, initial solution concentration, adsorbent mass, contact duration, and ambient temperature—on GO adsorption, employing the method of controlled variables. The adsorption efficacy is notably influenced by the pH level. At an acidic pH of 3, an initial GO concentration of 80 mg/L, an adsorbent dosage of 50 mg, and a temperature of 303 K (approximately 30 °C), the adsorption removal efficiency reaches an impressive 99 %, boasting a maximum adsorption capacity of 112 mg/g. Dynamically, the adsorption kinetics align most closely with a pseudo-first-order model, achieving equilibrium after 24 h. Thermodynamic analyses reveal that the Langmuir isotherm model most accurately describes the adsorption behavior, indicating an enhancement in BSP's adsorption capacity for GO as temperature rises. Based on thermodynamic equations, the adsorption of GO onto BSP is deduced to be a spontaneous process. Our findings illustrate BSP's considerable potential in the treatment and removal of GO from water, and therefore it may prove useful in environmental remediation efforts.

Immunogenic and toxic effects of graphene oxide nanoparticles in mouse skeletal muscles and human red blood cells

To investigate immunogenic and toxic effects of graphene oxide (GO) nanoparticles in mouse skeletal muscles and in human blood in vitro. GO nanoparticles prepared using a probe sonicator were supended in deionized H2O or PBS, and particle size and surface charge of the nanoparticles were measured with dynamic light scattering (DLS). Different concentrations (0.5, 1.0 and 2.0 mg/mL) of GO suspension or PBS were injected at multiple sites in the gastrocnemius muscle (GN) of C57BL/6 mice, and inflammatory response and immune cell infiltrations were detected with HE and immunofluorescence staining. We also examined the effects of GO nanoparticles on human red blood cell (RBC) morphology, hemolysis and blood coagulation using scanning electron microscope (SEM), spectrophotometry, and thromboelastography (TEG). GO nanoparticles suspended in PBS exhibited better colloidal dispersity, stability and surface charge effects than those in deionized H2O. In mouse GNs, injection of GO suspensions dose- and time-dependently resulted in sustained muscular inflammation and myofiber degeneration at the injection sites, which lasted till 8 weeks after the injection; immunofluorescence staining revealed obvious infiltration of monocytes, macrophages, dendritic cells and CD4+ T cells around the injection sites in mouse GNs. In human RBCs, incubation with GO suspensions at 0.2, 2.0 and 20 mg/mL, but not at 0.002 or 0.02 mg/mL, caused significant alterations of cell morphology and hemolysis. TEG analysis showed significant abnormalities of blood coagulation parameters following treatment with high concentrations of GO. GO nanoparticles can induce sustained inflammatory and immunological responses in mouse GNs and cause RBC hemolysis and blood coagulation impairment, suggesting its muscular toxicity and hematotoxicity at high concentrations.

Strengthening effect of monolayer graphene oxide on the impact mechanical properties of concrete and the mechanism analysis based on fractal theory

Graphene oxide (GO), a new nanomaterial with excellent properties, having the prospect of improving the performance of cementitious composites. Graphene oxide reinforced concrete (GORC) was prepared and the impact tests were performed through a φ100 mm SHPB test apparatus, to investigate the effects of impact velocity and GO content on the impact mechanical properties of concrete. The effects of GO on the pore structure and microscopic morphology of concrete were analyzed by MIP and SEM tests. Furthermore, the pore structure fractal dimension and fragment fractal dimension were calculated to quantitatively relate the microscopic pore structure to the macroscopic impact mechanical properties, and the enhancement mechanism of GO was investigated from microstructure optimization and stress dispersion mechanism. The results show that GO promotes the growth and aggregation of cement hydration products, and significantly improves the quasi-static and impact mechanical properties of concrete through filling-compacting effect and anticracking-unloading effect. When the GO content is 0.06 wt %, GO shows the best improvement effect. Compared with plain concrete (PC), the quasi-static compressive strength, dynamic compressive strength, elastic modulus, DIF, peak strain, ultimate strain and impact toughness are increased by a maximum of 29.95 %, 52.27 %, 9.79 %, 75 %, 51.54 %, 59.6 % and 86.2 % respectively. GORC has an obvious strain rate effect in the impact velocity range of 5.5 m/s-9.5 m/s, and the average particle size of specimen fragments satisfies a logarithmic relationship with the impact velocity. In addition, the pore structure fractal dimension and fragment fractal dimension satisfy a positive correlation. Larger pore structure fractal dimension indicates more defects in concrete and worse mechanical properties of it.

Emergence of enhanced photocatalytic response in GO-hBN nanocomposites with tuned non-linear optical and surface electronic properties

The hexagonal Boron Nitride (hBN) nanostructures with tuned physicochemical properties find huge applications in optoelectronic devices. Herein, we have synthesized nanocomposite of hBN with graphene oxide (GO) in various ratios to acquire composition-dependent variation in their structural, surface electronic, linear, and non-linear optical properties. The insertion of GO in hBN nanosheets has modified their strain landscape, the electronic charge transfers from GO to hBN, increased the working time of free charge carriers, and suppressed electron-hole recombination, thus modifying its work function (WF). GO-hBN nanocomposites observed to have reduced bandgap where creation of defect induced mid-gap states lead to enhancement in non-linear absorption of two photons. Herein, we have established a linear relationship between Urbach energy (Eu), a measure of disorders and non-linear absorption coefficient (αNL). Additionally, we have observed that the tuned bandgap of the nanocomposites has significantly enhanced their performance as high-performance photocatalysts for the degradation of methyl orange, compared to bare hBN or GO. As a result, we discovered that Eu, αNL, WF and photodegradation activity of GO-hBN nanocomposites exhibit analogous variations in response to changes in the content of GO. Thus, by strategically prioritizing the modification of a single parameter while considering the potential effects on other relevant properties for application purpose, GO-hBN can effectively harness large spectrum areas for catalytic and optoelectronic applications.

In-situ crosslinking reaction of graphene oxide & waterborne epoxy resin to construct continuous phase anticorrosive coating

The mechanism of using graphene oxide as a two-dimensional filler to increase the path length of the corrosive medium to the metal surface is limited to improving the corrosion resistance of the coating. This study propose novel dispersion and in-situ crosslinking reaction mechanism for constructing water-based heavy-duty anticorrosive coatings by using graphene oxide (GO) and waterborne epoxy resin (WEP). The results showed that GO can be uniformly dispersed directly into WEP without complex functional modifications. Oxygen-containing functional groups on moleculars structure of GO&WEP co-polymerized with diethylenetriamine (DETA) forming a continuous phase film which improved the density of the coating. Characterization techniques such as Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal conductivity measurement instrument, pencil hardness tester, adhesion tester, salt spray corrosion test chamber, and electrochemical impedance spectroscopy (EIS) were used to evaluate coating structure and performance properties. The results showed that graphene characteristics enhanced physical properties and anti-corrosion performance of composite coatings. The construction mechanism of the coating is different from that of the current GO modified and dispersed in the coating as a two-dimensional filler to extend the path length of the corrosive medium to the metal surface. The coatings prepared by adding the optimum mass ratio of 0.1–0.2 % GO to WEP have the best physical properties and anti-corrosion properties. When the GO content is 0.2 wt%, the thermal conductivity increases by 86.0 %. After added 0.025 wt% GO, the coating hardness is increased by two grades directly from 2B to HB. With the addition of GO concentration increased to 0.05 wt%, the adhesion is increased from 2 to level 1.When the GO content exceeds 0.05 %, the coating will not bulge off after 4 months of salt water immersion experiment.