Preparation Of Graphene Oxide Research Articles

Graphene oxide–lithium-ion batteries: inauguration of an era in energy storage technology

Abstract A significant driving force behind the brisk research on rechargeable batteries, particularly lithium-ion batteries (LiBs) in high-performance applications, is the development of portable devices and electric vehicles. Carbon-based materials, which have finite specific capacity, make up the anodes of LiBs. Many attempts are being made to produce novel nanostructured composite anode materials for LiBs that display cycle stability that is superior to that of graphite using graphene oxide. Therefore, using significant amounts of waste graphene oxide from used LiBs represents a fantastic opportunity to engage in waste management and circular economy. This review outlines recent studies, developments and the current advancement of graphene oxide-based LiBs, including preparation of graphene oxide and utilization in LiBs, particularly from the perspective of energy storage technology, which has drawn more and more attention to creating high-performance electrode systems.

Thiourea modulated supercapacitive behavior of reduced graphene oxide

In this report, we investigated the role of the concentration of nitrogen and sulfur containing thiourea in modulating the electrochemical properties of reduced Graphene Oxide (rGO) by controlling the percentage of heteroatoms on the rGO surface. The synthesis route involved the preparation of Graphene Oxide (GO) using an improved method of synthesis in an economical way by reducing the volume of concentrated acids used. Furthermore, GO is reduced by using different mass proportions of thiourea via a simple reflux method. Characterization of the rGO samples by Fourier Transform Infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDAX) and elemental analysis through CHNS analyzer exhibited successful doping and impact of nitrogen and sulfur atoms on the graphene framework. The comparative electrochemical performance from Cyclic Voltammograms (CV), Galvanostatic Charge Discharge (GCD) profiles and Electrochemical Impedance Spectroscopy (EIS) measurements on the various rGO samples revealed the superiority of 1:8rGO having 15.190 wt% of nitrogen and 26.849 wt% of sulfur and S/N ratio of 1.768, in delivering highest specific capacitance of 465.21 F·g−1 at 1 mV·s−1 scan rate with a remarkable cyclic stability exhibiting a capacitive retention of 119 % and offering lowest charge transfer resistance and diffusion resistance. The study also demonstrated detrimental effect of excess thiourea on electrochemical properties of rGO. This work suggests an effective and simple approach for optimizing the nitrogen and sulfur content in rGO to enhance its electronic properties using thiourea.

Freshly Prepared Graphene Oxide Nanoparticles’ Wound-Healing Potential and Antibacterial Activity Specifically Against Staphylococcus aureus: In Vivo Efficacy and Clinical Isolate Evaluation

Freshly Prepared Graphene Oxide Nanoparticles’ Wound-Healing Potential and Antibacterial Activity Specifically Against Staphylococcus aureus: In Vivo Efficacy and Clinical Isolate Evaluation

Investigation on Structural, Optical, and Thermal Properties of Graphene Oxide (GO) Nanoparticles

The aim of the study , A nanoparticles of graphene oxide (GO) was synthesized by modified Hummer’s method. A new approach to synthesis graphene is oxidizing graphite powder with mixture with concentrated Sulphuric acid (H2SO4), Sodium Nitrate (Na NO3) and Potassium permanganate (KMnO4), Currently,an improved method for the preparation of graphene Oxide was most common one. The Graphene Oxide (GO) was characterized by X-Ray diffractration, FT-IR Spectroscopy, UV Visible Spectroscopy , Raman Spectroscopy and TGA analysis. The X-ray diffractration (XRD) results of Graphene oxide nanoparticles was found to be 12.9 nm with a hexagonal crystal structure. Key Words: Graphene oxide, Hummer’s method,Graphite, X-ray diffratcration, FI-IR analysis,UV-Visible spectroscopy ,Raman spectroscopy and TGA-DTA analysis

Microwave assisted self-repairable vitrimeric coating for anti-corrosive applications

Vitrimeric coatings are revolutionary and most widely emerging materials for metal corrosion inhibition. As harsh environmental conditions damages polymer-derived protective films and results into micro cracks and corroded metal surfaces. In this work, an active microwave responsive vitrimeric epoxy coating embedded with weathering resistant properties is introduced along with systematic comparative study for the effect of ortho and para position of amine in hardening agent. The developed microwave radiation responsive coating system felicitates self-healing due to disulfide exchange mechanism and corrosion inhibition properties in marine environments. Compared to conventional coatings, prepared graphene oxide (GO) incorporated vitrimeric network showed more promising protection against corrosion in offshore applications with 95.4 % protection efficiency and hydrophobicity with 96-degree contact angle. This study covers the self-healing properties, thermal mechanical study, hydrophobicity measurement, and thorough corrosion examination of synthesized material coated on 304 grade SS substrate. The coating reports excellent self-healing efficiency, reliable mechanical strength (storage modulus-129GPa and loss modulus-83GPa), fast stress relaxation and low activation energy (63KJ/mol) for dynamic disulfide exchange reaction, furthermore low corrosion rate of 1.20 × 10−3mm/y was observed for the coating. Thus, demonstrates its importance for self-healable anti-corrosive application for the marine environment.

Development of an efficient, low-operating-pressure graphene oxide/polyethersulfone nanofiltration membrane for removing various water contaminants

Conventional wastewater treatment technologies tend to be high-capex, energy-intensive solutions that lack specificity for different pollution classes, and do not lend themselves to wide-scale deployment, particularly in areas of the world where industrial wastewater discharge is a significant environmental problem. In tandem, solid waste pollution arising, particularly plastic containing waste, is a persistent and serious pollution issue. This work focuses on the concept of "waste treating waste" and a multidisciplinary effort ranging from materials science and environmental management to sustainable water treatment, in addition to production of graphene oxide from mineral water waste bottles using a simple synthetic procedure that can be economically scaled up for use as a cost-effective adsorbent. Prepared graphene oxide was supported on a polyethersulfone (PES) membrane, and batch filtration studies were performed to examine its performance in the removal of methylene blue (MB) dye, Gentimicin sulphate (GMS) antibiotic, and Na2SO4 and MgSO4 salts from an aqueous solution. Operating parameters such as initial pollutant concentration, time, and solution pH were investigated and optimized using a response surface methodology (RSM) model. The results confirm the significant efficiency of the filtration process, with a maximum rejection of about 91% for MB, 93% for GMS, 67% for Na2SO4, and 64% for MgSO4, with maximum water flux of 1322, 1367, 1225, and 1059 LMH, respectively. Density functional theory calculations were considered for the GO, PES membrane, and GO/PES membrane with a GGA/PBE optimization level. Adsorption annealing locator analysis was performed for the GO/PES membrane, and the process was recalculated for MB as adsorbate. In conclusion, the adsorption effect employing produced GO/PES membrane is the most important removal, followed by Donnan exclusion and steric hindrance effect. Therefore, it is possible to build new eco-friendly membranes for nanofiltration that are affordable, stable, and effective in removing various pollutants from water systems.

The role of organic solvent and nano-additives loading in preparing and characterizing graphene oxide based polystyrene nanocomposites

ABSTRACT In this work, two types of organic solvents: namely, dimethylformamide (DMF) and tetrahydrofuran (THF); were investigated individually to prepare graphene oxide (GO) based polystyrene (PS) nanocomposites. Both were effective exfoliation agents for GO nano-sheets using sonication process. However, DMF showed poor solubility for PS beads compared to THF due to its high boiling point, poor volatility, and the prevailing monomer–monomer interaction rather than monomer–solvent interaction. Hot pressing was not an efficient preparatory approach for those samples prepared by DMF. Hence, solution casting, and THF were adopted to prepare PS and its GO-based nanocomposites. (0.5 and 1.0) wt. % of GO were dispersed homogeneously in PS using different dispersive techniques. Range of properties were tested for the pure polymer and its GO-based nanocomposites prepared by THF. A good dispersion of GO nano-sheets in PS was observed by different microscopic techniques. A significant improvement of mechanical and thermo-mechanical (storage modulus) performances for the polymer nanocomposites (PNCs) were achieved compared to the pure polymer. Young’s modulus for PS/GO nanocomposites was improved by 122% and 143% for GO loadings of 0.5 and 1.0 wt. %; respectively, and storage modulus for the nanocomposites recorded a considerable promotion compared to the pure polymer.

Evaluating the physico-mechanical performance of cement mortar reinforced with metakaolin/graphene oxide dual nano-additives

Researchers interested in producing high-mechanical-performance cement-based structures follow many strategies to achieve this purpose; one of these is the dual addition of materials. The current study was used thermal activation and chemical exfoliation to successfully prepare nano-metakaolin (NMK), whereas Hummers’ traditional technique was followed to prepare graphene oxide (GO). The key aim of this investigation was to promote the mechanical performance of cement mortars by incorporating both NMK and GO in the same matrix, where very few studies have examined the usage of both NMK and GO in the same cement matrix. For this purpose, six groups of plain and blended mortars were cast, with the cement being partially replaced with 10% NMK and GO being added at ratios of 0.01–0.04 wt.% of cement. The pore size distribution of the prepared mortars was studied using the nitrogen adsorption method, while phase composition/decomposition analysis was recognized by TGA and XRD. The microstructure was investigated by SEM. The obtained results revealed a great enhancement of splitting tensile strength by about 71% and about 20% for compressive strength, in addition to the refinement of the pore structure and promotion of the hydration reaction as confirmed by XRD, TGA, and SEM analysis.

Optimisation of the glycerol acetylation process using graphene oxide catalyst

Glycerol diversification from biodiesel production can be improved by converting it into high-value acetin products, for example, glyceryl monoacetate (MAG), glyceryl diacetate (DAG) and glyceryl triacetate (TAG) via the glycerol acetylation process with graphene oxide as a catalyst synthesised from Multi-Walled Carbon Nanotubes (MWCNT). Hummer's method was used to prepare graphene oxide. The acidity of the catalyst was examined, as well as FTIR, BET, XRD and SEM-EDX. This research aims to improve the glycerol acetylation to produce high glycerol conversion and acetins selectivity depending on the reaction circumstances. Process optimisation employs Response Surface Methodology (RSM) in conjunction with the Box-Behnken Design (BBD) method with three repeats of the midpoint. Temperature, mole ratio and catalyst loading (%) were all evaluated factors. The RSM process was optimised using Design-Expert software version 13, which resulted in a glycerol conversion of 93.04%. Moreover, with the selectivity of MAG 47.65%, DAG 29.21%, and TAG 23.36% at a temperature of 110°C, the mole ratio of glycerol and acetic acid (1:9) and the catalyst loading are 5%.

A method for the preparation of graphene from spent graphite of retired lithium-ion batteries

Recycling spent graphite is significant for the sustainable development of the lithium-ion industry. In this study, due to the damaged structure of spent graphite, a modified Hummers' method combined with thermal reduction is proposed to achieve the preparation of graphene and the simultaneous removal of impurities from the spent graphite. In the preparation of graphene oxide, the results show that the optimum mass ratio of spent graphite to oxidizing agent (KMnO4) is 1:3, under which the C/O and ID/IG values of graphene oxide are 1.99 and 1.52, respectively. The residual contents of various metal impurities in graphene oxide are lower than 100 ppm, and the impurities removal efficiency is better than that by acid leaching with the same acid dosage. After thermal reduction, reduced graphene oxide with a disordered few-layer structure is successfully prepared. It shows that spent graphite as a raw material for the preparation of graphene is superior to commercial graphite in terms of cost, and processing one ton of spent graphite yields a profit of $52,651.4. Our research can realize the diversified and efficient utilization of spent graphite and has a broad industrial application prospect.

Oxidative Desulfurization of Simulated Diesel Fuel by Synthesized Tin Oxide Nano-Catalysts Support on Reduced Graphene Oxide

The modified Hummers method was applied to prepare graphene oxide (GO) from the graphite powder. Tin oxide nanoparticles with different loading (10-20 wt.%) supported on reduced graphene oxide were synthesized to evaluate the oxidative desulfurization efficiency. The catalyst was synthesized by the incipient wetness impregnation (IWI) technique. Different analysis methods like FT-IR, XRD, FESEM, AFM, and Brunauer-Emmett-Teller (BET) were utilized to characterize graphene oxide and catalysts. The XRD analysis showed that the average crystal size of graphene oxide was 6.05 nm. In addition, the FESEM results showed high metal oxide dispersions on the rGO. The EDX analysis shows the weight ratio of Sn is close to its theoretical weight. The reduction of metal oxide and (GO) has occurred in one step at temperatures of 400 °C for 2 hours. The performance of the catalysts for dibenzothiophene (DBT) removal using H2O2 as an oxidizing agent was determined under a range of different operating conditions. The results showed that the maximum desulfurization was 71.68% in the best conditions (DBT concentration = 385 ppm, time = 90 min, temperature = 60 oC, catalyst dosage = 0.04g, and amount of oxidant = 0.375 ml).

Graphene oxide a promising formaldehyde scavenger of phenolic resin‐bonded plywood: From elaboration to evaluation

AbstractA long‐standing manufactured and most frequently used resin is phenol‐formaldehyde resin, which has currently reached new horizons by incorporating nano reinforcements, even at lower loadings. Nanostructured materials, particularly graphene, have gained considerable interest in recent years because of their fascinating characteristics. Herein, this study explores for the first time the potential of prepared graphene oxide (GnO) as an effective formaldehyde scavenger in the development of plywood panels containing PF resins. The addition of 1% of GnO to the system resulted in a significant improvements in the mechanical properties by more than 45% in the shear strength (SS), 35% in modulus of elasticity, and 25% in modulus of rupture when compared with the reference panel. While the moisture resistance of panels were found to remarkably enhanced showing an increase in SS by 25% and 37% After 24 h in cold water (20°C) and 12 h of immersion in boiling water, respectively. The results also demonstrated that GnO exhibited exceptional formaldehyde capture efficiency, surpassing 60% reduction compared with the control. This innovative research not only unveils the novel potential of GnO in improving the performance of PF resins but also ushers in a new way of developing eco‐friendly wood‐based materials.

Application of Graphene Technology in the Removal of Heavy Metal Ions in Wastewater

Nowadays, heavy metal pollution has become a serious problem. Toxic heavy metal ions can result in extreme damage to the environment and human society. Under that situation, methods that can remove the heavy metal ions in water have been required. Graphene technology can be widely applied to the removal of heavy metal ions. This article will explain the preparation of graphene oxide and reduced graphene oxide and the efficiency and influence factors of the method applied in water treatment. The method can remove many kinds of mainly occurring toxic heavy metal ions with very high efficiency. Also, large-scale production of graphene oxide can be achieved. The removal of heavy metal ions in water by graphene technology can be a practical method in the water treatment field.

Synthesis of M-type hexaferrite reinforced graphene oxide composites for electromagnetic interference shielding

This study focused on addressing the increasing demand for materials that can effectively shield against electromagnetic interference. In particular, Ba0.7Mn0.3Nd0.1Fe11.9O19 M-type hexaferrite was synthesized using the sol–gel auto-combustion method and sintered at 1050 °C. The modified Hummer process was used to prepare graphene oxide (GO), and three composites were then synthesized with the ultrasonication method, which were denoted as C-1 (90 % M-ferrite + 10 % GO), C-2 (80 % M-ferrite + 20 % GO), and C-3 (70 % M-ferrite + 30 % GO). X-ray diffraction (XRD) analysis confirmed the formation of the hexagonal phase of the M-type barium hexaferrite and GO. A prominent peak at an angle of 8.82° corresponding to the (001) reflection was observed by XRD analysis for the GO sample and it confirmed the effective oxidation of graphite and formation of GO. Scanning electron micrographs of M-type hexaferrite demonstrated the formation of platelet-like grains with hexagonal shapes, which were suitable for microwave absorption. The direct current electrical resistivity at room temperature was determined as 2.08 × 10−8 Ω-cm for the M-type ferrite, and the resistivity of the composites decreased as the concentration of GO increased due to the superior conductivity of GO compared with the ferrite. The dielectric properties of all samples followed the Maxwell–Wagner model. The dielectric characteristics increased in magnitude as the GO content increased. The AC magnetic susceptibility decreased for the M-type ferrite and three composites as the temperature increased to eventually reach a steady state at a specific temperature known as the Curie temperature. Except for GO, the Curie temperatures of all samples were within the range of 348 K–450 K. Coupling magnetic ferrite with GO allows the magneto-electrical characteristics to be tuned, with possible uses in electronic devices, electromagnetic shielding, supercapacitors, and water purification.

Synthesis Of Graphene Oxide Modified Polyaniline And Its Electrochemical Application For Detection of Nitric Oxide

Nitric oxide plays a crucial and important role in cellular physiology and also functions as a human cancer signaling molecule. Nitric oxide (NO) also exhibits antimicrobial and antitumor properties. However, conventional detection methods have their own limitations in the detection of NO at low concentrations because of its high reactivity and low lifetime. Here, we report a strategy to graphene oxide (GO)-modified polyaniline with efficiency to detect NO at a low concentration by electrocatalytic method. For this study we prepared graphene oxide polyaniline (GO-PANI) which has higher stability and stronger catalytic activity towards the oxidation of nitric oxide (NO).The synthesized compound was characterized by field emission scanning electron microscopy (FESEM) and UV-visible spectroscopy. With further modification of Nafion, the determination of NO in PBS with different concentration .This investigation offers a different method for determination of NO.

Green synthesis of reduced graphene oxide anchored Fe3O4‐Pd hetero‐nanostructure: An efficient, magnetically separable and reusable catalyst for Beckmann rearrangement of aldoximes to amides

The multifaceted Fe3O4‐Pd@rGO nanocomposite (NC) has been synthesized successfully by a biogenic method using Ocimum tenuiflorum leaf extract. The preparation of graphene oxide (GO) was done by the well‐known modified Hummer method. The as‐synthesized Fe3O4‐Pd@rGO NC was extensively characterized by various analytical techniques, namely, Fourier transform infrared (FTIR), X‐ray diffraction (XRD), field emission scanning electron microscopy‐energy‐dispersive X‐ray spectroscopy (FESEM‐EDX), high‐resolution transmission electron microscopy (HRTEM), inductively coupled plasma‐atomic emission spectrometry (ICP‐AES), X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM) and Brunauer–Emmett–Teller (BET) surface area analysis. The absence of peak corresponding to υ(CO) at 1732 cm−1 in the FTIR spectrum of Fe3O4‐Pd@rGO enumerates the reduction of GO to reduced graphene oxide (rGO) during Fe3O4‐Pd nanoparticle (NP) synthesis with O. tenuiflorum leaf extract. The XRD pattern reveals the existence of rGO, cubic‐phased spinel‐structured Fe3O4 along with the formation of metallic Pd NP without any impurities. The FESEM image designates the spherical and flake‐like morphology of the NC. The crystallite size of the NC was calculated employing the Debye–Scherrer equation and was found to be 3.45 nm corresponding to the (220) plane. The average particle size of Fe3O4‐Pd NPs as estimated from the particle size distribution curve was ascertained as 3.03 nm. The utmost saturation magnetization value of the NC as evaluated by VSM study has appeared at 0.6219 emu g−1 having coercivity value of 335.1 Oe and remanent magnetization value of 0.0767 emu g−1, suggesting the existence of a ferromagnetic material in the synthesized NC. It was a stable and highly efficient catalyst for Beckmann rearrangement of aldoximes using in an environment‐friendly medium. It afforded up to 99% isolated yield of the preferred products under acid‐free condition, avoiding the use of any harsh chemicals that will be beneficial for future industrial applications. Finally, the magnetic component of the NC allowed for easy recovery of the catalyst, thereby eliminating the chance of leaching of metal atoms, and was reusable till six successive cycles without apparent loss of its catalytic performance.

Preparation of graphene oxides functionalized with ferrocene for the thermal decomposition of ammonium perchlorate

Ferrocene (Fc)-based compounds as the burning rate catalysts (BRCs) for the thermal decomposition of ammonium perchlorate (AP), a vital oxidizer in composite solid propellants (CSPs), were received extensive attention due to its excellent catalytic effect. However, most of them are easy to migrate and the in situ produced metal oxide nanoparticles at high temperature tend to agglomerate, affecting the catalytic efficiency. Herein, a series of GOs functionalized with Fc were fabricated and studied as BRCs in this work. The results showed that these compounds can accelerate AP decomposition and enhance the combustion performance of CSPs, which was ascribed to the good thermal conductivity, electrical conductivity, larger steric hindrance and specific surface area. Among them, GOCu-AMTZ-Fc showed the best catalytic performance. The pyrolysis temperature of AP was reduced from 420.9 °C to 337.6 °C. Meanwhile, the burning rate of propellant was increased from 1.64 mm/s to 2.20 mm/s and the related pressure index was decreased by nearly half. Moreover, their anti-migration ability was improved greatly. The work indicated that GOs functionalized with Fc have a potential application as BRCs in CSPs.

Investigation on spilled oil absorption ability of graphene oxide coated melamine sponge

In this 21stcentury due to rise in population there is a great demand for the energy rise in domestic and industrial sector most of our energy demand is meet through fossil fuels. The fossil fuels are non-renewable energy sources such as coal, crude oil and natural gas. The crude oil and other petroleum products are available in large quantities under the ocean. These crude oil is extracted by drilling under the deep ocean through oilrigs and transported the oil and natural gas through container ships. There is a lot of chance for the accidents to occur during transporting oil and the spillage of crude oil causes serious environmental pollution. To reduce the damage to marine ecosystem caused due to oil spill Fabrication of cost-effective and robust hydrophobic and oileophilic sponge for easy clean-up of oil spills is a highly desired way. Here we developed a novel porous melamine sponge coated with reduced graphene oxide. The reduced graphene oxide is synthesized via modified hummer’s method. The sponge is fabricated by using dip coating method. The prepared graphene oxide sponge has to be characterized by scanning electron microscope. The dip coating process increases the absorption capacity of the prepared graphene oxide sponge and the absorption capacity of RGOMS has been tested by using motor oil, pump oil, gasoline, and diesel.

Easy-to-prepare graphene-based inkjet-printed electrodes for diclofenac electrochemical sensing

Inkjet-printed electrodes (IPEs) from flexible Kapton® as substrate and easy to prepare graphene oxide (GO)-based inks (K/GO) were prepared using a standard desktop printer. Subsequently, they were submitted to a post-processing thermal treatment (K/GO_TR400) and assessed as disposable working electrodes (WEs) for diclofenac (DCF) indirect electrochemical detection at pH 7.0 (close to physiological pH value). DCF monitoring is attracting much interest, due to its classification as contaminant of emerging concern in water sources. The performance of the printed active sensor material was compared to that of thermally reduced (at 400 °C) graphene oxide (TRGO-400, in a powder form), which has been successfully used as glassy carbon electrode (GCE) modifier for the detection of DCF. This electrode worked linearly within the concentration range between 5 and 25 μM with an LOD value of 2.25 μM. Moreover, the morphology and chemical composition of the obtained IPEs were characterized by means of scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) and compared with GCE/TRGO-400. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements using a miniaturized 3-electrode cell of the post-processed IPEs showed a promising electrochemical performance for DCF sensing. Thus, this study demonstrated the effective partial recovery of the valuable properties of graphene on the IPEs after the thermal treatment and the successful production of flexible and disposable electrodes for target analyte detection. Therefore, this is a promising alternative to conventional modified GCEs, as it offers a facile approach for the fabrication of cutting edge graphene-based electrodes and widens the available portfolio of electrochemical sensors towards detection of water contaminants of emerging concern.

Preparation of graphene oxide composited zinc oxide films by electrostatic spray deposition for humidity sensors

This work aimed to study the preparation of graphene oxide (GO) and zinc oxide (ZnO) composited films by electrostatic spray deposition for use in fabricated humidity sensors. The physical properties of prepared films were examined with X-ray diffraction, Raman spectroscopy, and scanning electron microscope. Subsequently, a humidity sensor was fabricated using a low-cost interdigitated electrode pattern with the print circuit board. The humidity sensing behaviors were assessed with fixed humidity levels in a saturated aqueous salt solution in the humidity range of 11 – 93%RH. The impedance value of the device was obtained with a precision LCR meter. It was found that the composited film of 0.50 %wt. GO demonstrated the highest humidity response with optimized humidity sensitivity, hysteresis error, and response/recovery times of 2.68 ´ 103, 4.89%, and 228/19 s, respectively. Moreover, the equivalent circuits for the prepared device at various humidity levels were acquired with impedance spectroscopy to propose the mechanism for the humidity sensing of the device.