Graphene Oxide Flakes Research Articles

Large-Scale Self-Assembly of anisotropic graphene oxide films via blade Coating: Sustainable design and Stimuli-Responsive performance for biomimicry

Sustainable structural design, utilizing material to imitate natural biological systems, presents both promise and challenges. By avoiding interfacial problems encountered in composite counterparts, such designs offer self-adaptive materials for smart housing and green architecture, etc. In this study, we demonstrate the feasibility of large-scale self-assembly of graphene oxide (GO) flakes into anisotropic films through a simple blade coating technique. Through the application of blade coating to a highly concentrated nematic GO suspension, we successfully fabricate GO films with morphological gradient and patterning. Additionally, we propose a statistical analysis method utilizing scanning electron microscopy (SEM) images for the characterization of materials with macroscopic surface morphology. Furthermore, we explore the application of these GO films as low-dimensional soft actuators, revealing their outstanding stimuli-responsive performance and self-adaptation to environment. Such robust and flexible films can be used as integral building elements in the bioinspired design of sustainable smart housing facilitating remote robotization and sensing capabilities.

Enhanced interlayer adhesion of wetted graphene oxide by confined water bridge.

Graphene oxide (GO) sheets are widely used as building blocks in flexible electronic devices, structural materials, and energy storage technology owing to physicochemical flexibility and remarkable mechanical properties. GO exists as lamellar structures in these applications and, thus, it urges to enhance interface interaction to prevent interfacial failure. This study explores the adhesion of GO with and without intercalated water utilizing steered molecular dynamics (SMD) simulations. We find the interfacial adhesion energy (γ) depends on the synergistic effect of the types of functional groups, the degree of oxidation (c), and water content (wt). The intercalated monolayer water confined within GO flakes can improve the γ by more than 50% whereas the interlayer spacing is enlarged. The enhancement of adhesion is from the cooperative hydrogen bonding bridges between confined water and functional group on GO. Furthermore, the optimal water content wt = 20% and oxidation degree c = 20% are obtained. Our findings provide an experimentally available way to improve interlayer adhesion through molecular intercalation, which opens the possibility of high-performance laminate nanomaterial-based films for versatile applications.

Fabrication of graphene oxide-modified self-healing microcapsules for Cardanol-based epoxy anti-corrosion coatings

In this paper, graphene oxide (GO) modified microcapsules have been developed for use in self-healing Cardanol-based epoxy anti-corrosion coatings on steel substrates. The microcapsules had a polymethyl methacrylate (PMMA) shell, covered with aminated GO flakes and contained either of the two complementary healing agents mixed with nanosized GO flakes. One set of capsules contained epoxidized nanosized GO and Cardanol-based epoxy resin, while the other contained aminated nanosized GO and Cardanol-based amine curing agent. The microcapsules had a narrow size distribution with a peak value of 4 μm. The Cardanol-based coatings containing various fractions of up to 20 wt% microcapsules in their stoichiometric ratio showed excellent anti-corrosion and self-healing properties. FT-IR, XPS, AFM, and Raman spectroscopy were used to characterize the size and chemical composition of the GO. Optical microscopy and SEM were used for morphological characterization. Double cantilever test upon bulk samples showed an excellent load transfer across the fracture plane after only 1 day curing at room temperature. The anti-corrosion properties of the Cardanol-based coating containing the two-component microcapsules were tested using electrochemical impedance spectroscopy (EIS). It was found that, after 60-day immersion in 3.5 wt% NaCl solution, the low-frequency impedance modulus |Z|0.01Hz of the Cardanol-based coating containing GO-modified microcapsules was three orders of magnitude higher than that of the systems with capsules without GO. After scratching the coating containing 20 wt% GO-modified microcapsules and exposing it to an aqueous 3.5 wt% NaCl solution, the |Z|0.01Hz of the Cardanol-based coating returned over a period of 7 days to the original value.

Tuning Structural Defects on a Nominal Single-Layered Graphene Oxide Membrane for Selective Separation of Biomolecules.

Two-dimensional (2D) materials provide a great opportunity for fabricating ideal membranes with ultrathin thickness for high-throughput separation. Graphene oxide (GO), owing to its hydrophilicity and functionality, has been extensively studied for membrane applications. However, fabrication of single-layered GO-based membranes utilizing structural defects for molecular permeation is still a great challenge. Optimization of the deposition methodology of GO flakes could offer a potential solution for fabricating desired nominal single-layered (NSL) membranes that can offer a dominant and controllable flow through structural defects of GO. In this study, a sequential coating methodology was adopted for depositing a NSL GO membrane, which is expected to have no or minimum stacking of GO flakes and thus ensure GO's structural defects as the major transport pathway. We have demonstrated effective rejection of different model proteins (bovine serum albumin (BSA), lysozyme, and immunoglobulin G (IgG)) by tuning the structural defect size via oxygen plasma etching. By generating appropriate structural defects, similar-sized proteins (myoglobin and lysozyme; molecular weight ratio (MWR): ∼1.14) were effectively separated with a separation factor of ∼6 and purity of 92%. These findings may provide new opportunities of using GO flakes for fabricating NSL membranes with tunable pores for applications in the biotechnology industry.

Morphology and Dynamics in Hydrated Graphene Oxide/Branched Poly(ethyleneimine) Nanocomposites: An In Silico Investigation.

Graphene oxide (GO)-branched poly(ethyleneimine) (BPEI) hydrated mixtures were studied by means of fully atomistic molecular dynamics simulations to assess the effects of the size of polymers and the composition on the morphology of the complexes, the energetics of the systems and the dynamics of water and ions within composites. The presence of cationic polymers of both generations hindered the formation of stacked GO conformations, leading to a disordered porous structure. The smaller polymer was found to be more efficient at separating the GO flakes due to its more efficient packing. The variation in the relative content of the polymeric and the GO moieties provided indications for the existence of an optimal composition in which interaction between the two components was more favorable, implying more stable structures. The large number of hydrogen-bonding donors afforded by the branched molecules resulted in a preferential association with water and hindered its access to the surface of the GO flakes, particularly in polymer-rich systems. The mapping of water translational dynamics revealed the existence of populations with distinctly different mobilities, depending upon the state of their association. The average rate of water transport was found to depend sensitively on the mobility of the freely to move molecules, which was varied strongly with composition. The rate of ionic transport was found to be very limited below a threshold in terms of polymer content. Both, water diffusivity and ionic transport were enhanced in the systems with the larger branched polymers, particularly with a lower polymer content, due to the higher availability of free volume for the respective moieties. The detail afforded in the present work provides a new insight for the fabrication of BPEI/GO composites with a controlled microstructure, enhanced stability and adjustable water transport and ionic mobility.

Maximized internal scattering in heterostack Ti3C2T x MXene/graphene oxide film for effective electromagnetic interference shielding

Two-dimensional (2D) MXenes have attracted significant attention in electromagnetic interference (EMI) shielding applications due to their excellent metallic conductivity, high surface area, 2D geometry, tunable surface chemistry, and solution processability. In this study, we present a straightforward way of introducing multiple nanoscale interfaces into Ti3C2T x MXenes using insulating graphene oxide (GO) intercalants to enhance internal scattering, resulting in improved EMI shielding effectiveness (SE). The amine-functionalized MXene with positive surface charge and negatively charged GO flakes are electrostatically self-assembled to form a 2D/2D heterostack of MXene/GO nanosheets. The resultant 2D/2D alternating heterostack of MXene/GO bearing multiple internal interfaces with significant impedance mismatch enhances the internal scattering of incident electromagnetic (EM) waves. Interestingly, despite their inferior electrical conductivity, the MXene/GO heterostack films exhibit higher EMI SE values than the randomly mixed hybrid films, and even outperform pristine MXene films. These MXene/GO heterostack films with enhanced absorption of EM waves via the strong internal scattering effect suggest a valuable pathway toward practical EMI shielding with thin and lightweight features.

Universal Strategy for Reversing Aging and Defects in Graphene Oxide for Highly Conductive Graphene Aerogels.

The production of highly stable, defect-free, and electrically conducting 3D graphene structures from graphene oxide precursors is challenging. This is because graphene oxide is a metastable material whose structure and chemistry evolve due to aging. Aging changes the relative composition of oxygen functional groups attached to the graphene oxide and negatively impacts the fabrication and properties of reduced graphene oxide. Here, we report a universal strategy to reverse the aging of graphene oxide precursors using oxygen plasma treatment. This treatment decreases the size of graphene oxide flakes and restores negative zeta potential and suspension stability in water, enabling the fabrication of compact and mechanically stable graphene aerogels using hydrothermal synthesis. Moreover, we employ high-temperature annealing to remove oxygen-containing functionalities and repair the lattice defects in reduced graphene oxide. This method allows obtaining highly electrically conducting graphene aerogels with electrical conductivity of 390 S/m and low defect density. The role of carboxyl, hydroxyl, epoxide, and ketonic oxygen species is thoroughly investigated using X-ray photoelectron and Raman spectroscopies. Our study provides unique insight into the chemical transformations occurring during the aging and thermal reduction of graphene oxide from room temperature up to 2700 °C.

Flame modified graphene oxide: Structure and sorption properties

The applications of graphene oxide (GO), advancing on its layered structure, such as selectively permeating membranes and sorption, heavily depend on changing/controlling the distance between the constituting layers. For the sorption, it is also critical to impede exfoliation of GO in solution to simplify the post-sorption separation. In this study, we demonstrate a new method for modifying the structure of solid graphite oxide. The method involves ultrafast passing of graphite oxide particles through a flame of a propane-oxygen gas burner. The resulted material (GOgts) retains the particulate morphology of the original graphite oxide, but has interlayer openings of varying width. The surface area of GOgts is increased 27 times, due to massive formation of narrow 3.5–6.0 nm sized pores. Chemically, GOgts retains the fine chemical structure of original GO with partial deoxygenation. State of the art HRTEM analysis reveals different structure of different GO layers, depending on their closeness to the formed openings. Some layers have large intact graphenic domains with the size of >30 nm. Finally, GOgts exhibits good sorption properties with respect to methylene blue, demonstrating higher sorption capacity, and faster kinetics than the original graphite oxide. Most importantly, in solution, GOgts particles do not disintegrate to single-atomic-layer sheets, affording simple separation of used GOgts from the purified water. The method of GOgts production is simple, scalable and can be used to create new filters for wastewater treatment. Methodologically, we perform HRTEM analysis of GO flake, comprising structurally different layers, with atomic resolution by applying selective Fourier filtering.

Graphene Oxide Membranes for Ionic/Molecular Filtration: From Self-Assembly to Design

The graphene oxide (GO) membrane holds great promise in desalination and green energy fields due to its naturally occurring nanochannels, which provide significant advantages in gas and ion filtration. In this study, the sizes and distributions of nanopore/channels in GO membranes and the relationship of GO flakes size and membrane thickness are explored by molecular dynamics simulations. Our results demonstrate that the size of GO flakes influences the distribution of nanopore sizes in GO membranes, while it almost has no influence on the total nanopore area in membranes with the same thickness. Additionally, our findings confirm that the total nanopore area of the GO membranes decreases exponentially as the membrane thickness increases, which is consistent with experimental observations. To expand the range of nanopore size regulation, we developed a columnar-array substrate model to create GO membranes customized for specific filtration functions, such as virus filtration. Our findings provide physical insights into the rational design of functional membranes for energy and environmental applications and offer theoretical guidance and technical support for the practical application of GO membranes in separation and filtration.

Controlled deposition of graphene oxide on an anodic aluminum oxide substrate via coffee-ring effect

The suppression of the coffee-ring effect is important for obtaining uniform colloid deposition. In this study, the controlled deposition of graphene oxide on anodic aluminum oxide (AAO) through the suppression of the coffee-ring effect was investigated. The effect of factors such as the AAO’s thickness and pore diameter, the external temperature, and the applied electric potential on downward capillary flow through pores in the presence of outward capillary flow associated with the coffee-ring effect was studied. When graphene oxide (GO) suspension was drop-casted on an AAO substrate, an increasing AAO thickness led to enhanced downward capillary flow, which suppressed the coffee-ring effect. An increase in the pore diameter resulted in greater suppression the coffee-ring effect since GO flakes could not completely block the pore entrance. Furthermore, an elevated temperature suppressed the coffee-ring effect on the AAO substrate through the rapid evaporation of the droplet, which reduced the outward capillary flow. When an electric potential was applied to the droplet, the downward capillary flow improved because of electrowetting and the outward capillary flow was reduced by the Coulomb force. In particular, the effect of the varied electric potential was adjusted by the AAO thickness. These observations indicated that the coffee-ring effect could be suppressed by appropriately setting the outward and downward capillary flows on the AAO substrate. Furthermore, the pore diameter had a stronger influence than the AAO thickness on the drop-casted GO film’s thickness. Notably, optimized GO film manipulation and GO film thickness control could be achieved by manipulating the hydrodynamic flow. The findings of this study have the potential to be used in applications such as filtration, gas separation, and wearable sensors, where a uniform thin film is required.

Domain Localization by Graphene Oxide in Supported Lipid Bilayers.

The gel-phase domains in a binary supported lipid bilayer (SLB) comprising dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) were localized on graphene oxide (GO) deposited on a SiO2/Si substrate. We investigated the distribution of the gel-phase domains and the liquid crystalline (Lα) phase regions in DOPC+DPPC-SLB on thermally oxidized SiO2/Si substrates with GO flakes to understand the mechanism of the domain localization on GO. Fluorescence microscopy and atomic force microscopy revealed that the gel-phase domains preferably distributed on GO flakes, whereas the fraction of the Lα-phase increased on the bare SiO2 surface which was not covered with the GO flakes. The gel-phase domain was condensed on GO more effectively at the lower cooling rate. We propose that nucleation of the gel-phase domain preferentially occurred on GO, whose surface has amphiphilic property, during the gel-phase domain formation. The domains of the liquid ordered (Lo) phase were also condensed on GO in a ternary bilayer containing cholesterol that was phase-separated to the Lo phase and the liquid disordered phase. Rigid domains segregates on GO during their formation process, leaving fluid components to the surrounding region of GO.

Optimization of bandgap reduction in 2-dimensional GO nanosheets and nanocomposites of GO/iron-oxide for electronic device applications

In this report we have developed different fabrication parameters to tailor the optical bandgap of graphene oxide (GO) nanosheets to make it operational candidate in electronic industry. Here we performed two ways to reduce the bandgap of GO nanosheets. First, we have optimized the oxidation level of GO by reducing amount of oxidizing agent (i.e. KMnO4) to control the sp2/sp3 hybridization ratio for a series of GO nanosheets samples. We noticed the reduction in primary band edge 3.93–3.2 eV while secondary band edge 2.98–2.2 eV of GO nanosheets as the amount of KMnO4 is decreased from 100 to 30%. Second, we have fabricated a series of 2-dimensional nanocomposites sample containing GO/Iron-oxide by using a novel synthesis process wet impregnation method. XRD analysis of synthesized nanocomposites confirmed the presence of both phases,alpha-Fe2O3 and Fe3O4 of iron-oxide with prominent plane (001) of GO. Morphological investigation rules out all the possibilities of agglomerations of iron oxide nanoparticles and coagulation of GO nanosheets. Elemental mapping endorsed the homogeneous distribution of iron oxide nanoparticles throughout the GO nanosheets. Raman spectroscopy confirmed the fairly constant ID/IG ratio and FWHM of D and G peaks, thus proving the fact that the synthesis process of nanocomposites has no effect on the degree of oxidation of GO flakes. Red shift in G peak position of all the nanocomposites samples showed the electronic interaction among the constituents of the nanocomposite. Linear decrease in the intensity of PL (Photoluminescence) spectra with the increasing of Iron oxide nanoparticles points towards the increased interaction among the iron oxide nanoparticles and GO flakes. Optical absorption spectroscopy reveals the linear decrease in primary edge of bandgap from 2.8 to 0.99 eV while secondary edge decrease 3.93–2.2 eV as the loading of alpha-Fe2O3 nanoparticles is increased from 0 to 5% in GO nanosheets. Among these nanocomposites samples 5%-iron-oxide/95%-GO nanosheet sample may be a good contestant for electronic devices.

Production of Graphene/Inorganic Matrix Composites through the Sintering of Graphene Oxide Flakes Decorated with CuWO4·2H2O Nanoparticles.

There is growing interest in graphene-reinforced inorganic matrix composites, but progress in this field is far behind that of polymer matrices due to difficulties in the processing of carbon materials in aggressive sintering environments, including oxidation and solubility in the host matrix. Copper-tungsten matrices are of particular interest in the power switching field but are difficult to produce due to the mutual insolubility of metals and poor wetting. Herein, composites were produced by decorating graphene oxide flakes with 8 nm diameter CuWO4·2H2O nanoparticles and then sintering them to form the final shape. The oxide nanoparticles were found to self-assemble into platelets on the surfaces of graphene flakes. Upon sintering, the presence of graphene was found to change the grain morphology from elongated needles to a polyhedral shape. It was found that, despite the nanosize of the CuWO4·2H2O particles used, the sintering conditions did not reduce the matrix to a pure metal; the sintered composites were found to be of mixed phase with copper tungstate and copper oxide present. Raman spectroscopy indicated that the graphene oxide became hydrogenated during the sintering process as a result of the reducing hydrogen atmosphere used.

Evaluation of electrosynthesized reduced graphene oxide-Ni/Fe/Co-based (oxy)hydroxide catalysts towards the oxygen evolution reaction.

In this work, the specific role of the addition of graphene oxide (GO) to state-of-the-art nickel-iron (NiFe) and cobalt-nickel-iron (CoNiFe) mixed oxides/hydroxides towards the oxygen evolution reaction (OER) is investigated. Morphology, structure, and OER catalytic activity of the catalysts with and without GO were studied. The catalysts were fabricated via a two-step electrodeposition. The first step included the deposition of GO flakes, which, in the second step, were reduced during the simultaneous deposition of NiFe or CoNiFe. As a result, NiFe-GO and CoNiFe-GO were fabricated without any additives directly on the nickel foam substrate. A significant improvement of the OER activity was observed after combining NiFe with GO (OER overpotential η(10 mA·cm-2): 210 mV) compared to NiFe (η: 235 mV) and GO (η: 320 mV) alone. A different OER activity was observed for CoNiFe-GO. Here, the overall catalytic activity (η: 230 mV) increased compared to GO alone. However, it was reduced in comparison to CoNiFe (η: 224 mV). The latter was associated with the change in the morphology and structure of the catalysts. Further OER studies showed that each of the catalysts specifically influenced the process. The improvement in the OER by NiFe-GO results mainly from the structure of NiFe and the electroactive surface area of GO.

Mussel – Inspired biosorbent combined with graphene oxide for removal of organic pollutants from aqueous solutions

In this work, we develop a mussel-inspired biosorbent combined with graphene oxide for removal of organic dyes in water sources. The composite was prepared via self-polymerization of dopamine in weak alkaline solution containing graphene oxide at ambient condition. Morphological and structural studies revealed that polydopamine has gradually grown to cover the surface of graphene oxide flakes, partially reduced these flakes, and somehow form many grains (size around 20 nm) on the flakes instead of making very large aggregates as usual. The mass ratio between two components of the composite was also investigated to find the optimal one which provides enough surface area (20 m2.g−1) and maintain adhesive sites in order to ensure high-efficiency removal of organic molecules. The adsorption kinetics and isotherms of as-prepared adsorbent towards methylene blue were found to fit well with pseudo-first order kinetics model and Langmuir isotherm. The maximum adsorption capacity (qm) and Langmuir constant (kL) were estimated to be 270 mg.g−1 and 0.49 L. mg−1. The as-prepared bio-sorbent is very promising for remediation of water sources contaminated with cationic organic molecules and heavy metal ions.

Thickness measurements of graphene oxide flakes using atomic force microscopy: results of an international interlaboratory comparison

Flake thickness is one of the defining properties of graphene-related 2D materials (GR2Ms), and therefore requires reliable, accurate, and reproducible measurements with well-understood uncertainties. This is needed regardless of the production method or manufacturer because it is important for all GR2M products to be globally comparable. An international interlaboratory comparison on thickness measurements of graphene oxide flakes using atomic force microscopy has been completed in technical working area 41 of versailles project on advanced materials and standards. Twelve laboratories participated in the comparison project, led by NIM, China, to improve the equivalence of thickness measurement for two-dimensional flakes. The measurement methods, uncertainty evaluation and a comparison of the results and analysis are reported in this manuscript. The data and results of this project will be directly used to support the development of an ISO standard.

Probing the Gelation Synergies and Anti-Escherichia coli Activity of Fmoc-Phenylalanine/Graphene Oxide Hybrid Hydrogel.

The N-fluorenyl-9-methyloxycarbonyl (Fmoc)-protected amino acids have shown high antimicrobial application potential, among which the phenylalanine derivative (Fmoc-F) is the most well-known representative. However, the activity spectrum of Fmoc-F is restricted to Gram-positive bacteria only. The demand for efficient antimicrobial materials expanded research into graphene and its derivatives, although the reported results are somewhat controversial. Herein, we combined graphene oxide (GO) flakes with Fmoc-F amino acid to form Fmoc-F/GO hybrid hydrogel for the first time. We studied the synergistic effect of each component on gelation and assessed the material's bactericidal activity on Gram-negative Escherichia coli (E. coli). GO flakes do not affect Fmoc-F self-assembly per se but modulate the elasticity of the gel and speed up its formation. The hybrid hydrogel affects E. coli survival, initially causing abrupt bacterial death followed by the recovery of the surviving ones due to the inoculum effect (IE). The combination of graphene with amino acids is a step forward in developing antimicrobial gels due to their easy preparation, chemical modification, graphene functionalization, cost-effectiveness, and physicochemical/biological synergy of each component.

Fabrication of high-strength graphene oxide/carbon fiber nanocomposite membranes for hydrogen separation applications

Graphene oxide (GO) is a promising nanosheet for developing next-generation thin-membrane technology to enhance gas permeability and selectivity performance based on the interlayer spacing principle. This study aimed to strengthen GO membranes for enhancing gas permeability and selectivity using non-woven carbon fiber (CF) fabric. The GO/CF membranes were synthesized with 1 wt% of GO and different CF orientations in the matrices with various GO layer thicknesses (200–800 µm). The resulting membranes were characterized for their surface and cross-sectional morphology, pore sizes, mechanical, chemical, and thermal analysis. The SEM results showed successful deposition of GO flakes onto the CF surface with high cohesion with the fibers, accompanied by some deviations in the GO edges, allowing gases to pass through the membranes. In addition, thinner membranes had higher Young's modulus (56 MPa) and surface roughness in the ranges of 84–184 nm. While the gas permeability measurements revealed that the thinner membranes (200 µm) had higher gas permeability in the range 7809214 Barrer (CO2) and 23154004 Barrer (H2) with an increase of 68–92% compared to the thicker membranes (600 and 800 µm). Moreover, thinner membranes showed higher selectivities about 5.2 (H2/CO2), 4.3 (H2/N2) and 3.6 (H2/CH4). Overall, these results indicate that GO/CF membranes are a promising solution for hydrogen separation due to their high strength and ease of fabrication.

Tuneable electrohydrodynamics of core-shell graphene oxide vortex rings

The vortex ring (VR) effect occurs when fluid droplets impact on another fluid, leading to toroidal flow within the impacting droplet due to viscous friction, resulting in a wide variety of flow-induced morphologies. When applied to dispersions of 2-dimensional materials, such as graphene oxide (GO) in water, the VR effect can be used to generate 3-dimensional assemblies of GO flakes. Here, we have taken advantage of the surface charge on GO flakes in water, interacting with cationic aqueous surfactant systems, to generate an electrohydrodynamic VR effect. This yields GO hydrogel and aerogel microparticles with complex axially symmetric shapes, with a core-shell structure featuring a shell of aligned GO flakes. Using high frame-rate optical imaging, we have captured the real-time self-assembly of GO core-shell hydrogel microparticles shaped like spheres, donuts and jellyfish. We describe, both qualitatively and quantitatively, the electrohydrodynamics that drive the formation of such shapes. We also demonstrate how the underlying processes can be tuned by varying parameters such as GO concentration, flake size and drop velocity, and surfactant chemistry and concentration to produce a wide variety of controllable exterior and interior morphologies. Indeed, we show that the formation regimes of the different shapes are determined by dimensionless Weber and Ohnesorge numbers. Lastly, we demonstrate how these microparticles can be used for the efficient adsorption and removal of anionic contaminants in water, with tuneable adsorption capacity.

A novel, efficient and economical alternative for the removal of toxic organic, inorganic and pathogenic water pollutants using GO-modified PU granular composite

Multicomponent wastewater treatment utilising simple and cost-effective materials and methods is an important research topic. This study has reported the fabrication and utilisation of graphene oxide (GO) embedded granular Polyurethane (PU) (GOPU) adsorbent for the treatment of lead ion (Lead ion (Pb(II)), Methylene blue (MB), and E. coli. PU granules were wrapped with GO flakes to improve hydrophilicity, interaction with polluted water, cation-exchange reaction, and binding of pollutants on its surface. Synthesised GOPU granules were characterised by X-Ray Diffraction (XRD), Raman, Fourier transform infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM) analysis to ensure the successful synthesis of GO and fabrication of GOPU granules. Further, batch and continuous adsorption processes were studied in different operating conditions to evaluate the performance of GOPU granules in practical applications. The kinetic and isotherm analyses revealed that the adsorption of Lead (Pb(II)) ion and Methylene Blue (MB) dye followed the Freundlich and Langmuir isotherm models, respectively, and they showed good agreement with the Pseudo-second-order kinetic model. The adsorption capacities of GOPU granules for the elimination of Pb(II) and MB dye were about 842 mg/g and 899 mg/g, respectively.Additionally, investigations into the fixed bed column revealed that the adsorption column performed best at a flow rate of 5 mL/min and a bed height of 6 cm. Pb(II) adsorption had a bed uptake capacity (qbed) of 88 mg/g and percentage removal efficiency (%R) of 76%. Similarly, MB adsorption had a bed uptake capacity of 202 mg/g and a percentage removal efficiency of 71%. A systematic invention on antibacterial activity toward E. coli showed that The GOPU granules have a removal efficiency of about 100% at an exposure of 24 h. These findings indicated the possible use of GOPU granules as promising adsorbents for various water pollutants.