Search results for: BILAYER GRAPHENE SHEETS
-
Mechanical analysis of eccentric defected bilayer graphene sheets considering the van der Waals force
PublicationIn this article, we have tried to simulate nonlinear bending analysis of a double-layered graphene sheet which contains a geometrical imperfection based on an eccentric hole. The first-order shear deformation theory is considered to obtain the governing equations. Also, the nonlinear von Kármán strain field has been assumed in order to obtain large deformations. Whereas the double-layered graphene sheet has been considered, the...
-
Thermal Buckling Analysis of Circular Bilayer Graphene sheets Resting on an Elastic Matrix Based on Nonlocal Continuum Mechanics
PublicationIn this article, the thermal buckling behavior of orthotropic circular bilayer graphene sheets embedded in the Winkler–Pasternak elastic medium is scrutinized. Using the nonlocal elasticity theory, the bilayer graphene sheets are modeled as a nonlocal double–layered plate that contains small scale effects and van der Waals (vdW) interaction forces. The vdW interaction forces between the layers are simulated as a set of linear springs...
-
The effects of confinement in pores built of folded graphene sheets on the equilibrium of nitrogen monoxide dimerisation reaction
Publication -
Bending and buckling formulation of graphene sheets based on nonlocal simple first-order shear deformation theory
PublicationThis paper presents a formulation based on simple first-order shear deformation theory (S-FSDT) for large deflection and buckling of orthotropic single-layered graphene sheets (SLGSs). The S-FSDT has many advantages compared to the classical plate theory (CPT) and conventional FSDT such as needless of shear correction factor, containing less number of unknowns than the existing FSDT and strong similarities with the CPT. Governing...
-
Growth and Isolation of Large Area Boron‐Doped Nanocrystalline Diamond Sheets: A Route toward Diamond‐on‐Graphene Heterojunction
PublicationMany material device applications would benefit from thin diamond coatings, but current growth techniques, such as chemical vapor deposition (CVD) or atomic layer deposition require high substrate and gas‐phase temperatures that would destroy the device being coated. The development of freestanding, thin boron‐doped diamond nanosheets grown on tantalum foil substrates via microwave plasma‐assisted CVD is reported. These diamond...
-
The effect of boron concentration on the electrical, morphological and optical properties of boron-doped nanocrystalline diamond sheets: Tuning the diamond-on-graphene vertical junction
PublicationIn this paper, the effect of boron doping on the electrical, morphological and structural properties of free-standing nanocrystalline diamond sheets (thickness ~ 1 μm) was investigated. For this purpose, we used diamond films delaminated from a mirror-polished tantalum substrate following a microwave plasma-assisted chemical vapor deposition process, each grown with a different [B]/[C] ratio (up to 20,000 ppm) in the gas phase....
-
Perovskite-type KTaO3–reduced graphene oxide hybrid with improved visible light photocatalytic activity
PublicationNovel rGO–KTaO3 composites with various graphene content were successfully synthesized using a facile solvothermal method which allowed both the reduction of graphene oxide and loading of KTaO3 nanocubes on the graphene sheets. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX), Fourier...
-
Interrelated shape memory and Payne effect in polyurethane/graphene oxide nanocomposites
PublicationWe report the fabrication of graphene oxide (GO) based polyurethane (PU) nanocomposites by a simple method of mixing and their shape memory properties at different temperatures. Both the polymer and the filler were synthesized in the laboratory by simple and easy methods – PU by pre-polymer method and GO by improved graphene oxide synthesis method. High molecular level dispersion of GO platelets within the PU matrix and thus good...
-
Dielectric properties of modified graphene oxide filled polyurethane nanocomposites and its correlation with rheology
PublicationThis study aims at investigating the dynamic mechanical, dielectric and rheological properties of reinforced polyurethane (PU) nanocomposites containing hydrophilic graphene oxide (GO) and/or hydrophobic modified graphene oxide (mGO) sheets. The organic modification of GO was performed with 4,4′-methylenebis (phenyl isocyanate) (MDI) and the samples were prepared by solvent mixing. We found that addition of mGO provides a more...
-
Synergistic effect of multi walled carbon nanotubes and reduced graphene oxides in natural rubber for sensing application
PublicationUtilizing the electrical properties of polymer nanocomposites is an important strategy to develop high performance solvent sensors. Here we report the synergistic effect of multi walled carbon nanotubes (MWCNTs) and reduced graphene oxide (RGO) in regulating the sensitivity of the naturally occurring elastomer, natural rubber (NR). Composites were fabricated by dispersing CNTs alone and together with exfoliated RGO sheets (thermally...
-
Titanium lanthanum three oxides decorated magnetic graphene oxide for adsorption of lead ions from aqueous media
PublicationThe current study presents a viable and straightforward method for synthesizing titanium lanthanum three oxide nanoparticles (TiLa) and their decoration onto the ferrous graphene oxide sheets to produce FeGO-TiLa as efficient magnetic adsorbent. Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and vibration sample magnetometer (VSM) were used to evaluate...
-
Buckling Analysis of a Micro Composite Plate with Nano Coating Based on the Modified Couple Stress Theory
PublicationThe present study investigates the buckling of a thick sandwich plate under the biaxial non-uniform compression using the modified couple stress theory with various boundary conditions. For this purpose, the top and bottom faces are orthotropic graphene sheets and for the central core the isotropic soft materials are investigated. The simplified first order shear deformation theory (S-FSDT) is employed and the governing differential...
-
Removal of lead ions from wastewater using lanthanum sulfide nanoparticle decorated over magnetic graphene oxide
PublicationIn this study, the new lanthanum sulfide nanoparticle (La2S3) was synthesized and incorporated onto magnetic graphene oxide (MGO) sheets surface to produce potential adsorbent (MGO@LaS) for efficient removal of lead ions (Pb2+) from wastewater. The synthesized MGO@LaS adsorbent was characterized using Fourier transform infrared spectroscopy, field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. The...
-
N-doped mesoporous carbon nanosheets obtained by pyrolysis of a chitosan–melamine mixture for the oxygen reduction reaction in alkaline media.
PublicationBy simple thermal decomposition of low-cost precursors (chitosan, melamine) in an inert atmosphere, nitrogen-doped porous carbonaceous materials were prepared. The samples pyrolyzed at 700 C are composed of mainly mesoporous nitrogen-doped carbon nanosheets and partially graphitized carbon. The nanosheets contain a disordered area due to the strain imposed by the presence of nitrogen and/or oxygen groups in their structure. Some...
-
A novel one-variable first-order shear deformation theory for biaxial buckling of a size-dependent plate based on Eringen’s nonlocal differential law
PublicationPurpose – This paper aims to present a new one-variable first-order shear deformation theory (OVFSDT) using nonlocal elasticity concepts for buckling of graphene sheets. Design/methodology/approach – The FSDT had errors in its assumptions owing to the assumption of constant shear stress distribution along the thickness of the plate, even though by using the shear correction factor (SCF), it has been slightly corrected, the errors...
-
Composite Materials Based on Polymer-Derived SiCN Ceramic and Disordered Hard Carbons as Anodes for Lithium-Ion Batteries
PublicationNew composite materials based on polymer-derived SiCN ceramics and hard carbons were studied in view of its application as anodes for lithium-ion batteries. Two kinds of composites were prepared by pyrolysis of the preceramic polysilazane (HTT1800, Clariant) at 1000 °C in Ar atmosphere mixed with hard carbons derived from potato starch (HC_PS) or with a hard carbon precursor, namely potato starch (PS), denoted as HTT/HC_PS and...
-
Water Behavior Near the Lipid Bilayer
PublicationIn this chapter, we focus on the dynamics of water molecules situated in the vicinity of a phospholipid bilayer. Using a molecular dynamics simulation method, we studied interactions between water and the bilayer and tracked trajectories of the water molecules. Based on the hypothesis that molecules trapped inside the bilayer make different motions than the ones which are either attached to the surface or move freely in the water...
-
Localization and Orientation of Xanthophylls in a Lipid Bilayer
PublicationXanthophylls (polar carotenoids) play diverse biological roles, among which are modulation of the physical properties of lipid membranes and protection of biomembranes against oxidative damage. Molecular mechanisms underlying these functions are intimately related to the localization and orientation of xanthophyll molecules in lipid membranes. In the present work, we address the problem of localization and orientation of two xanthophylls...
-
Stability of roof trusses stiffened by corrugated sheets
PublicationThe present parametric study is devoted to the stability analysis of a set of trusses stiffened by decking of corrugated steel sheets. For different parameters of corrugated sheets the critical loading of the roof is calculated. In the parametrical analysis the threshold bracing condition of the roof is obtained. Then the geometrically non-linear analysis of trusses braced by corrugated sheets was conducted. As a results of non-linear...
-
GRAPHENE IN GAS CHEMIRESISTORS
PublicationGraphene has a range of unique physical properties which could be exploited in gas sensing. Every atom of graphene may be considered as a surface atom, able to interact even with single molecule of the target gas or vapour species resulting in the ultrasensitive sensor response. In this paper the potential of graphene as a nanomaterial for fabricating chemiresistors was described. Recent development in graphene sensors was considered...
-
Comparison of Properties of the Hybrid and Bilayer MWCNTs—Hydroxyapatite Coatings on Ti Alloy
PublicationCarbon nanotubes are proposed for reinforcement of the hydroxyapatite coatings to improve their adhesion, resistance to mechanical loads, biocompatibility, bioactivity, corrosion resistance, and antibacterial protection. So far, research has shown that all these properties are highly susceptible to the composition and microstructure of coatings. The present research is aimed at studies of multi-wall carbon nanotubes in three different...
-
The Effect of Sterols on Amphotericin B Self-Aggregation in a Lipid Bilayer as Revealed by Free Energy Simulations
PublicationAmphotericin B (AmB) is an effective but toxic antifungal drug, known to increase the permeability of the cell membrane, presumably by assembling into transmembrane pores in a sterol-dependent manner. The aggregation of AmB molecules in a phospholipid bilayer is, thus, crucial for the drug’s activity. To provide an insight into the molecular nature of this process, here, we report an atomistic molecular dynamics simulation study...
-
Graphene Reinforced Phenolic Foams
PublicationPhenolic foams (PF) belong to the polymeric materials, which are very attractive from the point of many possible applications such as insulation or fire protection materials. This chapter attempts to explain the influence of graphene and graphene derivatives on the phenolic foams. This work briefly presents different graphene nanoparticles introduced to the phenolic foams matrix, in terms of impact on the thermal, mechanical, and...
-
NUCLEAR DATA SHEETS
Journals -
Graphene oxide, reduced graphene oxide and composite thin films NO2 sensing properties
PublicationA graphene oxide (GO), reduced graphene oxide (RGO) and poly(3,4-ethylenedioxytiophene)-reduced graphene oxide (PEDOT-RGO composite) gas sensors were successfully fabricated using an electrodeposition method. The electrodeposition was carried out in aqueous GO dispersions. To obtain RGO and PEDOT-RGO, the electrochemical reduction of GO and PEDOT-GO was carried out in 0.1 M KCl at a constant potential of −0.85 V. The GO, RGO and PEDOT-RGO...
-
Morphology, Mechanical and Thermal Properties of Thermoplastic Polyurethane Containing Reduced Graphene Oxide and Graphene Nanoplatelets
PublicationPolyurethane/graphene nanocomposites were synthesized using commercial thermoplastic polyurethane (TPU, Apilon 52DE55), and two types of graphene derivatives: graphene nanoplatelets (GNP) and reduced graphene oxide (RGO). Fourier Transformation Infrared Spectroscopy Fourier Transformation Infrared Spectroscopy (FTIR) spectroscopy, TEM, and SEM microscopy and XRD techniques were used to chemically and structurally characterize GNP...
-
Graphene Production and Biomedical Applications: A Review
PublicationGraphene is a two-dimensional nanomaterial composed of carbon atoms with sp2 hybrid orbitals. Both graphene and graphene-based composite have gained broad interest among researchers because of their outstanding physiochemical, mechanical, and biological properties. Graphene production techniques are divided into top-down and bottom-up synthesis methods, of which chemical vapor deposition (CVD) is the most popular. The biomedical...
-
Graphene oxide, reduced graphene oxide and composite thin films NO2 sensing properties
PublicationA graphene oxide (GO), reduced graphene oxide (RGO) and poly(3,4-ethylenedioxytiophene)- reduced graphene oxide (PEDOT-RGO composite) gas sensors were successfully fabricated using an electrodeposition method. The electrodeposition was carried out in aqueous GO dispersions. In order to obtain RGO and PEDOT-RGO, the electrochemical reduction of GO and PEDOT-GO was carried out in 0.1 M KCl at constant potential of −0.85 V. The GO, RGO...
-
Membrane Sterols Modulate the Binding Mode of Amphotericin B without Affecting Its Affinity for a Lipid Bilayer
PublicationMembrane-active antibiotics are known to selectively target certain pathogens based on cell membrane properties, such as fluidity, lipid ordering, and phase behavior. These are in turn modulated by the composition of a lipid bilayer and in particular by the presence and type of membrane sterols. Amphotericin B (AmB), the golden standard of antifungal treatment, exhibits higher activity toward ergosterol-rich fungal membranes, which...
-
Facile synthesis and characterization of graphene and N-doped graphene by CVD method from liquid precursors for promising electrode materials
PublicationIn this study, high-quality and few-layered graphene was synthesized using the chemical vapor deposition (CVD) method from liquid sources. Two different liquid carbon sources, pyridine, and benzene, were used and deposited on nickel foam under heat conditions using a bubbler in a quartz tube. X-ray diffraction (XRD) and Raman analysis confirmed the crystalline properties of graphene and N-doped graphene, demonstrating the high...
-
Optimization of Graphene Oxide Synthesis and Its Reduction
PublicationIn this article, we present the review of the chemical methods of synthesis of graphene oxide and its reduction in order to obtain the so-called reduced graphene oxide (rGO) whose properties are similar to those of pure graphene. We also present our experiments and the results in this field and the comparison of the efficiency of different methods of synthesis as well as the reduction of graphene oxide. To characterize the obtained...
-
Review of the Application of Graphene-Based Coatings as Anticorrosion Layers
PublicationDue to the excellent properties of graphene, including flexibility that allows it to adjust to the curvature of the substrate surface, chemical inertness, and impermeability, graphene is used as an anticorrosion layer. In this review, we present the current state-of-the-art in the application of graphene in the field of protective coatings. This review provides detailed discussions about the protective properties of graphene coatings...
-
RECENT ADVANCES IN GRAPHENE APPLICATION FOR ELECTRONIC SENSING
PublicationThe great interest in graphene is caused by its potential for constructing various sensors exhibiting excellent parameters. The high carrier mobility and the unique band structure of graphene makes it promising especially in the field-effect transistors (GFET) applications. In this article, recent advances of the selected graphene-based sensor applications were presented and the possible directions for further investigations were...
-
Reduced Graphene Oxide Joins Graphene Oxide To Teach Undergraduate Students Core Chemistry and Nanotechnology Concepts
PublicationNovel carbon nanomaterials such as reduced graphene oxide (rGO) and graphene oxide (GO) can be easily incorporated into the undergraduate curriculum to discuss basic chemistry and nanotechnology concepts. This paper describes a laboratory experiment designed to study the differences between GO and rGO regarding their physico-chemical properties (e.g. color, hydrophobicity, type of functional groups, electrical conductivity etc.)....
-
GRAPHENE-BASED SUPERCAPACITORS APPLICATION FOR ENERGY STORAGE
PublicationRecent advances in graphene-based supercapacitor technology for energy storage application were summarized. The comparison of different types of electrode materials in such supercapacitors was performed. The supercapacitors with graphene-based electrodes exhibit outstanding performance: high charge-discharge rate, high power density, high energy density and long cycle-life, what makes them suitable for various applications, e.g....
-
Applying of Doped Graphene Oxide Coatings for Corrosion Prevention
PublicationINTRODUCTION Graphene is a carbonaceous material characterized by extraordinary properties (high electron mobility, high surface area, high mechanical strength of 1100 GPa, very dense network hindering the passage of even the smallest helium atoms) [1]. Therefore, it found many applications, also as an anti-corrosive layer [2]. Electrophoretic Deposition (EPD) is one of the methods to deposit coatings. However, due to slight solubility...
-
3D porous graphene-based structures- synthesis and applications
PublicationPorous carbon-based materials are of the great industrial and academic interest due to their high surface area, low density, good electrical conductivity, chemical inertness and low cost of fabrication. Up to now, the main approach to obtain porous carbon structures has involved the pyrolysis of carbonaceous natural or synthetic precursors. After the isolation of graphene, the interest in 3D porous graphene-based structures (called...
-
Silica-templated three-dimensional graphene xerogels
PublicationMost porous carbons require the uniform pore size distribution therefore many approaches have been applied to template the carbon scaffolds and among them the use of silica particles is the easiest and the most effective. After discovering of graphene, the whole family of new carbon nanomaterials arose and one of the promising materials is graphene xerogel (GX) with a three-dimensional, highly porous structure. This monograph reviews...
-
Fully scalable one-pot method for the production of phosphonic graphene derivatives
PublicationGraphene oxide was functionalized with simultaneous reduction to produce phosphonated reduced graphene oxide in a novel, fully scalable, one-pot method. The phosphonic derivative of graphene was obtained through the reaction of graphene oxide with phosphorus trichloride in water. The newly synthesized reduced graphene oxide derivative was fully characterized by using spectroscopic methods along with thermal analysis. The morphology...
-
Modeling of photovoltaic properties of bilayer organic systems
PublicationPraca prezentuje teoretyczny opis charakterystyki prądowo-napięciowej i efektu fotowoltaicznego układu zbudowanego z dwóch warstw organicznych i elektrod. Rozpatrywane jest przybliżenie stałego pola elektrycznego oraz wpływ pułąpkowania nośników ładunku.
-
The protective properties of graphene oxide coatings functionalized with phosphorus atoms.
PublicationRecently, electrophoretically deposited graphene oxide coatings are commonly applied as an anti-corrosion layer. However, improper adjustment of electrophoretic deposition (EPD) parameters as well as the hydrophilic nature of graphene oxide contribute to the formation of defects in the coatings and the increase in the wetting properties, respectively, and thus lead to a reduction of protective properties. The growth of wetting...
-
Enhanced supercapacitor materials from pyrolyzed algae and graphene composites
PublicationThis study focuses on the synthesis and characterization of supercapacitor materials derived from pyrolyzed natural compounds. Four compounds were investigated: methylcellulose with lysine (ML), methylcellulose with lysine-graphene composite (MLG), algae (A), and algae-graphene composite (AG). The pyrolysis process was utilized to convert these natural compounds into carbon-based materials suitable for supercapacitor applications....
-
Recent and Emerging Applications of Graphene-based metamaterials in Electromagnetics
PublicationSurface Plasmon Polaritons (SPPs) operating in mid-infrared up to terahertz (THz) frequencies have been traditionally manufactured on expensive metals such as gold, silver, etc. However, such metals have poor surface confinement that limits the optical applications of SPPs. The invention of graphene is a breakthrough in plasmon-based devices in terms of design, fabrication and applications, thanks to its plasmonic wave distribution,...
-
New approach for the synthesis of Ag3PO4-graphene photocatalysts
PublicationA facile and effective plasma sputtering method for the preparation of a visible light active photocatalyst - rhombic dodecahedral silver phosphate Ag3PO4 covered with nanographene (Ag3PO4-GR) with improved stability has been developed. Proposed method allows for the usage of readily available materials for nanographene sputtering and for easy scaling-up. The stability improvement, confirmed by visible light-induced phenol degradation...
-
The electrical, morphological and optical properties of heavily boron-doped diamond sheets as a function of methane concentration in the gas phase
PublicationBoron-doped diamonds (BDD) are known for their excellent properties such as high thermal conductivity, high mobility, low absorption in visible light, and biocompatibility. In this work, we investigated the electrical, morphological and optical properties of heavily boron-doped diamond thin sheets as a function of methane concentration in the gas phase. Free-standing diamond sheets were fabricated using a microwave plasma-assisted...
-
Polyurethane Nanocomposites Containing Reduced Graphene Oxide, FTIR, Raman, and XRD Studies
PublicationRecently, graphene and other graphene-based materials have become an essential part of composite science and technology. Their unique properties are not only restricted to graphene but also shared with derivative compounds like graphene oxide, reduced graphene oxide, functionalized graphene, and so forth. One of the most structurally important materials, graphene oxide (GO), is prepared by the oxidation of graphite. Though removal...
-
Graphene field-effect transistor application for flow sensing
PublicationMicroflow sensors offer great potential for applications in microfluidics and lab-on-a-chip systems. However, thermal-based sensors, which are commonly used in modern flow sensing technology, are mainly made of materials with positive temperature coefficients (PTC) and suffer from a self-heating effect and slow response time. Therefore, the design of novel devices and careful selection of materials are required to improve the overall...
-
Elastic polyurethane foams containing graphene nanoplatelets
PublicationElastic polyurethane foams were produced from two-component polyurethane systems (SPECFLEX NE 113 izocyjanian/NR 816 poliol system—SPC and Elastic MBMarket company system POLYOL ET MB 500/ISO ET MB 800—ET) by using a one-step method. The foams were a graphene nanoplatelets (GNP) in the amount ranging from 1 to 2 wt.%. The effect of the nanofiller on polyurethane matrix was determined by analyzing the chemical structure, static...
-
Application of Barkhausen method to determine internal stresses in cold-rolled and hot-rolled sheets
PublicationThe paper presents investigations on internal stress distribution in plane hot—or cold-rolled sheets dedicated for the cold-formed profiles. The motivation of the research is a new profile design whose bending technology, incorporating a longitudinal welded joint and hot-dip galvanization after bending and welding introduces additional internal stresses. In order to identify the entirety of stresses in the process of sheet production...
-
Molecular Dynamics simulations of thermal conductivity of penta-graphene
PublicationThe thermal conductivity of penta-graphene (PG), a new two dimensional carbon allotrope and its dependence on temperature, strain, and direction are studied in this paper. The thermal conductivity of PG is investigated using a non-equilibrium molecular dynamics simulation (NEMD) with the Two Region Method by applying the optimized Tersoff interatomic potential. Our study shows that the thermal conductivity of PG (determined for...
-
Chemical modifications of graphene and their influence on properties of polyurethane composites: a review
PublicationPolyurethane composites are materials of great interest nowadays due to their wide range of available forms and applications in industry. Controlling and achieving unique properties via matrix modifications and addition of various specific nanofillers seems be one of the key elements to success. The purpose of this work is to briefly present some examples of graphene nanoderivatives, their syntheses, properties and influence on...
-
Reviewing the recent developments of using graphene-based nanosized materials in membrane separations
PublicationAccording to the potentialities of graphene-based materials and their unique physicochemical properties. Such 2D nanomaterials are likely to be the most implemented within the improvement of the selective separations of polymer membranes, together with enhanced physicochemical properties (such as hydrophilicity/hydrophobicity, transport of molecules, mechanical and thermal features, among others). Hence, this review compiles and...
-
Tailoring Graphene to Achieve Negative Poisson's Ratio Properties
PublicationGraphene can be made auxetic through the introduction of vacancy defects. This results in the thinnest negative Poisson's ratio material at ambient conditions known so far, an effect achieved via a nanoscale de-wrinkling mechanism that mimics the behavior at the macroscale exhibited by a crumpled sheet of paper when stretched.
-
Probability distribution of flicker noise in AuNPdecorated graphene–Si Schottky barrier diode
PublicationWe present results of the probability distribution analysis of flicker noise generated in Au nanoparticle (AuNP) decorated graphene–Si Schottky barrier diodes with and without yellow light illumination (592 nm), close to the localized surface plasmon resonance in the AuNPs (586 nm). The AuNPs occupy imperfections in the single-layer graphene and reduce the flicker noise intensity generated in the graphene layer. The estimated probability...
-
Imaging of graphene surface by means of tapping mode AFM
Open Research DataGraphene [1] is a material consisting of carbon planes with a hexagonal structure. One of the facts of interest from a purely scientific point of view is the very high mobility of electrons in the described material, allowing the study of relativistic effects inside a solid sample. Other features, such as bactericidal activity, make graphene an interesting...
-
Characterization of PVDF/Graphene Nanocomposite Membranes for Water Desalination with Enhanced Antifungal Activity
PublicationSeawater desalination is a worldwide concern for the sustainable production of drinking water. In this regard, membrane distillation (MD) has shown the potential for effective brine treatment. However, the lack of appropriate MD membranes limits its industrial expansion since they experience fouling and wetting issues. Therefore, hydrophobic membranes are promising candidates to successfully deal with such phenomena that are typical...
-
Comprehensive study on graphene hydrogels and aerogels synthesis and their ability of gold nanoparticles adsorption
PublicationGraphene hydrogels were prepared by ascorbic acid-assisted gelation of graphene oxide (GO) aqueous suspensions both in acidic and basic conditions. Different mass ratio of ascorbic acid (AA) to GO was used (namely 20:1 and 10:1). In order to eliminate the influence of AA on the final structure of hydrogels, samples without AA were prepared by a hydrothermal gelation of GO in an autoclave. An in-depth structural characterization...
-
Pulsed UV-irradiated Graphene Sensors for Ethanol Detection at Room Temperature
PublicationA graphene-based gas sensor fabricated in a FET (GFET) configuration and its sensitivity towards ethanol and methane is reported. Detection of ethanol at the level of 100 ppm was observed under pulsed UV irradiation and after cleaning by UV light in the N2 ambient. Reduction of the frequency of UV irradiation pulses resulted in increased changes in sensor resistance in the presence of ethanol. Improved sensing behavior was ascribed...
-
The behavioural model of graphene field-effect transistor
PublicationThe behavioural model of a graphene field-effect transistor (GFET) is proposed. In this approach the GFET element is treated as a “black box” with only external terminals available and without considering the physical phenomena directly. The presented circuit model was constructed to reflect steady-states characteristics taking also into account GFET capacitances. The authors’ model is defined by a relatively small number of equations...
-
Fabrication of anti-corrosion nitrogen doped graphene oxide coatings by electrophoretic deposition
PublicationThis work assesses anti-corrosion properties of graphene and N-doped graphene coatings deposited on copper by an electrophoretic method. Graphene oxide (GO) precursor was synthesized by an improved Hummers' method, whereas N-doping was performed hydrothermally in the presence of ammonia. After nitrogenation, doped graphene oxide samples (NGO) contained a reduced amount of oxygen and about 9% w/w nitrogen as pyridinic, pyrrole,...
-
Functionalization of graphene oxide coatings with phosphorus atoms and their corrosion resistance in sodium chloride environment
PublicationIn this work, we compared corrosion resistance of graphene oxide, and phosphorus functionalized reduced graphene oxide coatings obtained as a result of electrophoretic deposition on the copper substrate. Doping graphene oxide with phosphorus atoms was performed by a hydrothermal method in the presence of different amounts of phosphoric acid. Structural studies confirmed the insertion of phosphorus atoms into the graphene oxide...
-
Molecular Dynamics of a Vasopressin V2 Receptor in a Phospholipid Bilayer Membrane
Publication -
Graphene oxide thin films deposited on a PCB board - chemical analysis
Open Research DataGraphene oxides based films were measured by X-ray photoemission spectroscopy (XPS) method. TheXPS measurements were carried out with the Omicron NanoTechnology UHV equipment. The hemispherical spectrophotometer was equipped with a 128-channel collector. The XPS measurements were performed at room temperature at a pressure below 1.1 × 10−8 mBar. The...
-
Graphene Oxide as Mine of Knowledge: Using Graphene Oxide To Teach Undergraduate Students Core Chemistry and Nanotechnology Concepts
PublicationThe aim of this laboratory experiment is to utilize graphene oxide (GO) material to introduce under-graduate students to many well-known concepts of general chemistry. GO is a new nanomaterial that has generated worldwide interest and can be easily produced in every well-equipped undergraduate chemical laboratory. An in-depth examination of GO synthesis, as well as a study of its structure and properties, allows students to familiarize...
-
Microwave Characterization of Dielectric Sheets in a Plano-Concave Fabry-Perot Open Resonator
PublicationDespite its long history, a double-concave (DC) Fabry-Perot open resonator (FPOR) has recently gained popularity in the characterization of dielectrics in the 20–110 GHz range, mainly due to such novel accomplishments as full automation of the measurement process and the development of even ore accurate and computationally efficient electromagnetic model. However, it has been discovered that such a DC resonator suffers from unwanted...
-
Evaluating Gelatin-Based Films with Graphene Nanoparticles for Wound Healing Applications
PublicationIn this study, gelatin-based films containing graphene nanoparticles were obtained. Nanoparticles were taken from four chosen commercial graphene nanoplatelets with different surface areas, such as 150 m2/g, 300 m2/g, 500 m2/g, and 750 m2/g, obtained in different conditions. Their morphology was observed using SEM with STEM mode; porosity, Raman spectra and elemental analysis were checked; and biological properties, such as hemolysis...
-
Enhanced gas sensing by graphene-silicon Schottky diodes under UV irradiation
PublicationThe effect of ultraviolet (UV) or blue irradiation on graphene/n-doped silicon Schottky junctions toward gas sensing was investigated. Schottky diodes were subjected to oxidizing nitrogen dioxide (NO2, 1–3 ppm) and reducing tetrahydrofuran (THF, 50–200 ppm), showing significantly different responses observed on the currentvoltage (I-V) characteristics, especially under UV light (275 nm). NO2 affected the resistive part of the forward region...
-
Modelling of Graphene Field-Effect Transistor for lectronic sensing applications
PublicationA top-gated Graphene Field-Effect Transistor (GFET) suitable for electronic sensing applications was modelled. The applied simulation method reproduces correctly the output transfer GFET characteristics and allows to investigate doping effect caused by different physical, chemical or biological factors. The appearance of additional charge in the system results in the shift of the current-voltage characteristic. This feature could...
-
3D Hierarchical Boron-Doped Diamond-Multilayered Graphene Nanowalls as an Efficient Supercapacitor Electrode
PublicationSynthesis of stable hybrid carbon nanostructure for high-performance supercapacitor electrode with long life-cycle for electronic and energy storage devices is a real challenge. Here, we present a one-step synthesis method to produce conductive boron-doped hybrid carbon nanowalls (HCNWs), where sp2-bonded graphene has been integrated with and over a three-dimensional curved wall-like network of sp3-bonded diamond. The spectroscopic...
-
Thermo-resonance analysis of an excited graphene sheet using a new approach
PublicationForced vibration of graphene nanoplate based on a refined plate theory in conjunction with higher-order nonlocal strain gradient theory in the thermal environment has been investigated. Regarding the higher-order nonlocal strain gradient theory, both stress nonlocality and size-dependent effects are taken into account, so the equilibrium equations which are governing on the graphene sheet have been formulated by the theory....
-
Graphene-Coated PVDF Membranes: Effects of Multi-Scale Rough Structure on Membrane Distillation Performance
PublicationGraphene-coated membranes for membrane distillation have been fabricated by using a wet-filtration approach. Graphene nanoplatelets have been deposited onto PVDF membrane surfaces. Morphology and physicochemical properties have been explored to evaluate the changes in the surface topography and related effects on the membrane performance in water desalination. The membranes have been tested in membrane distillation plants by using...
-
Dynamics study on single and multiple β-sheets
Publication -
Laser patterned platform with PEDOT–graphene composite film for NO2 sensing
PublicationThis work presents a simple and fully electrochemical route used for fabricating of a NO2 gas sensor made of reduced-graphene-oxide-poly(3,4-ethylenedioxythiophene) composite film. The sensing platform was fabricated from alumina substrate and equipped with gold interdigitated electrodes and built-in heater.The temperature distribution on the surface of interdigitated electrodes was investigated by a thermalimaging camera and compared...
-
Graphene hydrogels with embedded metal nanopatricles as efficient catalysts in 4-nitrophenol reduction and methylene blue decolorization
PublicationSynthesis and characterization of the graphene hydrogels with three different metallic nanoparticles, that is Au, Ag and Cu, respectively is presented. Synthesized in a one-pot approach graphene hydrogels with embedded metallic nanoparticles were tested as heterogeneous catalysts in a model reaction of 4-nitrophenol reduction. The highest activity was obtained for graphene hydrogel with Cu NPs and additional reaction of methylene...
-
Electrical characteristics simulation of top-gated graphene field-effect transistor (GFET) with 10 μm x 10 μm graphene channel
Open Research DataThe presented data set is part of the research on graphene field-effect transistor (GFET) modelling. The calculations were performed with the use of GFET Tool program (https://nanohub.org/resources/gfettool DOI: 10.4231/D3QF8JK5T), which enabled simulation of the drain current (Id) vs. drain voltage (Vd) characteristics for different gate voltages (Vg)...
-
Electrical characteristics simulation of top-gated graphene field-effect transistor (GFET) with 10 μm x 3 μm graphene channel
Open Research DataThe presented data set is part of the research on graphene field-effect transistor (GFET) modelling. The calculations were performed with the use of GFET Tool program (https://nanohub.org/resources/gfettool DOI: 10.4231/D3QF8JK5T), which enabled simulation of the drain current (Id) vs. drain voltage (Vd) characteristics for different gate voltages (Vg)...
-
Novel Structures and Applications of Graphene-Based Semiconductor Photocatalysts: Faceted Particles, Photonic Crystals, Antimicrobial and Magnetic Properties
PublicationGraphene, graphene oxide, reduced graphene oxide and their composites with various compounds/materials have high potential for substantial impact as cheap photocatalysts, which is essential to meet the demands of global activity, offering the advantage of utilizing “green” solar energy. Accordingly, graphene-based materials might help to reduce reliance on fossil fuel supplies and facile remediation routes to achieve clean environment...
-
Interatomic potential suitable for the modeling of penta-graphene: Molecular statics/molecular dynamics studies
PublicationWe test the potentials available for elemental carbon, with the scope to choose the potential suitable for the modeling of penta-graphene, the latest two dimensional carbon allotrope. By using molecular statics and molecular dynamics simulations we show that there is only one potential e namely the Tersoff-type potential proposed by Erhart and Albe in 2005 e which is able to correctly describe all the important features of penta-graphene....
-
Synthesis, dispersion, and cytocompatibility of graphene oxide and reduced graphene oxide
Publication -
Effect of graphene thickness on photocatalytic activity of TiO2-graphene nanocomposites
Publication -
Electroactive polymer/graphene oxide nanostructured composites; evidence for direct chemical interactions between PEDOT and GOx
PublicationThis work concerns electrochemical synthesis of nanocomposites consisting of conducting polymer and reduced graphene oxide (rGOx) as electrode materials for supercapacitors. The electrosynthesis was performed in an aqueous solution of the 3,4-ethylenedioxytiophene (EDOT) monomer and graphene oxide (GOx) without supporting electrolyte. The amount of GOx was optimized to obtain the best electrochemical performance of the nanocomposite...
-
FTIR spectra and IGC chromatograms for chemically reduced graphene oxide aerogels (rGOA)
Open Research DataThe effect of selected synthesis parameters on reduced graphene oxide aerogels properties was investigated using Fourier-transform infrared spectroscopy and dynamic adsorption method (Inverse Gas Chromatography, IGC). Samples were synthesized by sol-gel method by reduction induced self-assembly of graphene oxide. As a reductant l-ascorbic acid was used....
-
Study of the effect of thermally reduced graphene oxide on the physical and mechanical properties of flexible polyurethane foams
PublicationFlexible polyurethane foams were obtained from a two-component system via the one-step method. The foams were modified with thermally reduced graphene oxide added in the amount equal to 0.25, 0.5 and 0.75 wt%. The morphology, static and dynamic properties, and thermal stability of modified foams were determined. The application of carbon filler resulted in the visible increase in the cell size, apparent density and rigidity of...
-
The effects of gas exposure on the graphene/AlGaN/GaN heterostructure under UV irradiation
PublicationThis work demonstrates a graphene/AlGaN/GaN sensing device with two-dimensional electron gas (2DEG) toward nitrogen dioxide (NO2), tetrahydrofuran, and acetone detection under UV light irradiation. We propose combining measurements of the DC characteristics with a fluctuation-enhanced sensing method to provide insight into the gas detection mechanisms in the synergistic structure of highly stable GaN and gas-sensitive graphene....
-
Capacitance Enhancement by Incorporation of Functionalised Carbon Nanotubes into Poly(3,4-Ethylenedioxythiophene)/Graphene Oxide Composites
PublicationThis paper reports on the role of oxidised carbon nanotubes (oxMWCNTs) present in poly-3,4-ethylenedioxytiophene (PEDOT)/graphene oxide (GOx) composite. The final ternary composites (pEDOT/GOx/oxMWCNTs) are synthesised by an electrodeposition process from the suspension-containing monomer, oxidised carbon nanotubes and graphene oxide. Dissociated functional groups on the surface of graphene oxide play a role of counter-ions for the...
-
Effect of Functionalization of Reduced Graphene Oxide Coatings with Nitrogen and Sulfur Groups on Their Anti-Corrosion Properties
PublicationElectrophoretic production of anticorrosion carbonaceous coatings on copper could be successfully performed by anodic oxidation of negatively charged graphene platelets suspended in an aqueous solution. The various platelets were synthesized by Hummer’s method followed by a hydrothermal reduction in the presence of NH4SCN which was expected to substitute some parts of graphene structure with nitrogen and sulfur groups. X-ray photoelectron...
-
Stability of cylindrical steel silos composed of corrugated sheets and columns based on FE analyses versus Eurocode 3 approach
PublicationComprehensive static and dynamic 3D stability finite element analyses of a cylindrical steel silo composed of corrugated sheets and open thin-walled vertical stiffener profiles were carried out by taking the geometric and material non-linearity into account. The silowas subjected to axisymmetric and non-axisymmetric loads imposed by a bulk solid following Eurocode 1. Theoretical and measured initial geometric imperfections were...
-
Synthesis and modification of reduced graphene oxide aerogels for biofuel cell applications
PublicationWe have carried out the preparation of reduced graphene oxide aerogels using eco-friendly method that is based on the Hummers method of graphite oxidation without the use of NaNO3 that produces toxic gases. To obtain a porous 3D structure of reduced graphene oxide, we performed the hydrothermal reduction at elevated temperature. We also prepared the rGO aerogel/CNT composite using multiwalled carbon nanotubes as linkers. The rGO...
-
High-performance graphene-based biosensor using a metasurface of asymmetric silicon disks
PublicationIn recent years, optical biosensors widely applicable for medical applications, have received much attention. In this paper, we propose a high-performance polarization-insensitive optical biosensor based on a graphene-dielectric metasurface. The metasurface consists of an asymmetric dielectric disk array that supports a high Q-factor Fano resonance. The provided sharp Fano resonance results in an enhanced light-matter interaction...
-
Solvent-Free Synthesis of Phosphonic Graphene Derivative and Its Application in Mercury Ions Adsorption
PublicationFunctionalized graphene was efficiently prepared through ball-milling of graphite in the presence of dry ice. In this way, oxygen functional groups were introduced into material. The material was further chemically functionalized to produce graphene derivative with phosphonic groups. The obtained materials were characterized by spectroscopic and microscopic methods, along with thermogravimetric analysis. The newly developed material...
-
XRD (X-ray diffraction) patterns of WS2/userGOx (composites of tungsten disulfide and ultrafast self-expanded and reduced graphene oxide), ex-WS2 (exfoliated tungsten disulfide) and GO (graphene oxide)
Open Research DataThese data contain XRD (X-ray diffraction) patterns of WS2/userGOx (composites of tungsten disulfide and ultrafast self-expanded and reduced graphene oxide), ex-WS2 (exfoliated tungsten disulfide) and GO (graphene oxide). The data were collected for samples obtained from three ex-WS2:GO dispersions - with 1:1, 1:2, and 2:1 weight ratios.
-
Low-frequency noise in Au-decorated graphene–Si Schottky barrier diode at selected ambient gases
PublicationWe report results of the current–voltage characteristics and low-frequency noise in Au nanoparticle (AuNP)-decorated graphene–Si Schottky barrier diodes. Measurements were conducted in ambient air with addition of either of two organic vapors, tetrahydrofuran [(CH2)4O; THF] and chloroform (CHCl3), as also during yellow light illumination (592nm), close to the measured particle plasmon polariton frequency of the Au nanoparticle...
-
Linear Pantographic Sheets: Existence and Uniqueness of Weak Solutions
Publicationwe address the well-posedness of the planar linearized equilibrium problem for homogenized pantographic lattices. To do so: (i) we introduce a class of subsets of anisotropic Sobolev’s space as the most suitable energy space E relative to assigned boundary conditions; (ii) we prove that the considered strain energy density is coercive and positive definite in E ; (iii) we prove that the set of placements for which the strain...
-
Molecular Dynamics of Complexes of Atosiban with Neurohypophyseal Receptors in the Fully Hydrated Phospholipid Bilayer
Publication -
Extension of the UNRES Coarse-Grained Force Field to Membrane Proteins in the Lipid Bilayer
Publication -
On the light intensity dependence of short-circuit current of bilayer organic photovoltaic cells
PublicationPraca przedstawia model zależności prądu zwarcia w organicznych dwuwarstwowych układach fotowoltaicznych od natężenia światła. Model jest oparty na założeniu jednorodnego pola elektrycznego w obu warstwach organicznych. Uwzględniona jest bimolekularna i monomolekularna rekombinacja nośników ładunku przy heterozłączu. Przedstawione zostało porównanie obliczeń teoretycznych i wyników doświadczalnych dla układów z barwnikiem perylenowym...
-
Morphology and the physical and thermal properties of thermoplastic polyurethane reinforced with thermally reduced graphene oxide
PublicationIn this study, thermally reduced graphene oxide (TRG)-containing polyurethane nanocomposites were obtained by the extrusion method. The content of TRG incorporated into polyurethane elastomer systems equaled 0.5, 1.0, 2.0 and 3.0 wt%. The morphology, static and dynamic mechanical properties, and thermal stability of the modified materials were investigated. The application of TRG resulted in a visible increase in material stiffness...
-
Analysis of graphene multi-strip planar guiding structures with the use of spectral domain approach
PublicationSpectral domain approach is modified and used to analyze some simple structures containing graphene strips. The modification is simple and concerns the Green’s function only. Moreover, the method is combined with the recently published root finding algorithms, which significantly improve the efficiency of the analysis. The results obtained for a simple guiding structure is verified and the field displacement effect is confirmed.
-
Tailoring properties of reduced graphene oxide by oxygen plasma treatment
PublicationWe report an easily controllable, eco-friendly method for tailoring the properties of reduced graphene oxide (rGO) by means of oxygen plasma. The effect of oxygen plasma treatment time (1, 5 and 10 minutes) on the surface properties of rGO was evaluated. Physicochemical characterization using microscopic, spectroscopic and thermal techniques was performed. The results revealed that different oxygen-containing groups (e.g. carboxyl,...
-
Towards Computer-Aided Graphene Covered TiO2-Cu/(CuxOy) Composite Design for the Purpose of Photoinduced Hydrogen Evolution
PublicationIn search a hydrogen source, we synthesized TiO2-Cu-graphene composite photocatalyst for hydrogen evolution. The catalyst is a new and unique material as it consists of copper-decorated TiO2 particles covered tightly in graphene and obtained in a fluidized bed reactor. Both, reduction of copper from Cu(CH3COO) at the surface of TiO2 particles and covering of TiO2-Cu in graphene thin layer by Chemical Vapour Deposition (CVD) were...