Low Degree Of Oxidation Research Articles

Electrochemical synthesis and property characterisation of graphene oxide using water as electrolyte

Graphene oxide (GO) sheets were synthesized using tap water as the electrolyte in an electrochemical exfoliation method, that is cost-effective, environmentally friendly and relatively simple. The effects of electrode materials, i.e. carbon fibre sheets and graphite rod, and different intensities of electrical current on the final properties of GO were explored by UV–Vis spectroscopy, Raman spectroscopy, X-ray Photoelectron spectroscopy and transmission electron microscopy measurements. Experimental results showed that highly dispersed GO materials could be successfully prepared even when tap water was used as the electrode, thus avoiding any strong oxidative electrolytes. Furthermore, both the electrode materials and the different intensities of electrical current could influence the properties of the resulting GO materials. When the electrical current increased, the concentration of GO in water also increased with the formation of more defects and carboxyl groups (OCO), but fewer epoxy or hydroxyl groups (CO) and a lower oxidation degree. Additionally, an increased current intensity led to the formation of smaller GO particles, with particle size range dependent on the electrodes. Carbon fiber sheets appear to be preferable for large-scale productions of GO due to more controllable size range, significantly higher concentration and fewer overlapped layers when compared to the graphite rods at a given electrical current.

Adsorption of Single and Multiple Graphene-Oxide Nanoparticles at a Water-Vapor Interface.

The adsorption of graphene-oxide (GO) nanoparticles at the interface between water and vapor was analyzed using all-atom molecular simulations for single and multiple particles. For a single GO particle, our results indicate that the adsorption energy does not scale linearly with the surface coverage of oxygen groups, unlike typically assumed for Janus colloids. Our results also show that the surface activity of the particle depends on the number of surface oxygen groups as well as on their distribution: for a given number of oxygen groups, a GO particle with a patched surface was found to be more surface active than a particle with evenly distributed groups. Then, to understand what sets the thickness of GO layers at interfaces, the adsorption energy of a test GO particle was measured in the presence of multiple GO particles already adsorbed at the interface. Our results indicate that in the case of high degree of oxidation, particle-particle interactions at the water-vapor interface hinder the adsorption of the test particle. In the case of a low degree of oxidation, however, clustering and stacking of GO particles dominate the adsorption behavior, and particle-particle interactions favor the adsorption of the test particle. These results highlight the complexity of multiple particle adsorption and the limitations of single-particle adsorption models when applied to GO at a relatively high surface concentration.

Chemostratigraphy of the Carajás banded iron formation, Brazil: A record of Neoarchean Ocean chemistry

One of the most important occurrences of banded iron formation (BIF) worldwide is situated in the Carajás Mineral Province, southeastern Amazonian Craton. The BIFs are jaspilites and are hosted in the Neoarchean (∼2.74 Ga) volcano-sedimentary sequence of the Grão-Pará Group. They are mostly composed of cm-thick intercalations of hematite, jasper, and chert. Their primary textures and structures are still preserved, which make them an ideal archive to evaluate the paleomarine environment. Low abundance of Al2O3 (<1.0 wt%) and HFSE (<1 ppm) for most BIF samples indicate an essentially detritus-free depositional environment. Overall, the rare earth elements and yttrium (REY) patterns show a weak positive lanthanum (La) anomaly, and a pronounced positive europium (Eu) anomaly (Eu/EuPAAS = 1.86 – 5.05), although the presence of true cerium (Ce) anomaly is not evident. Stratigraphic variations in iron isotope compositions, up to 0.80‰ (δ56Fe = +1.10 to +1.90‰) over tens to hundreds of meters of stratigraphic section, point to relative changes in the iron isotope composition of Carajás seawater over periods of a few million years. The jaspilites show heterogeneous distribution of Nd isotopic signature throughout the BIF sequence, and rocks from near the basaltic flows/jaspilite contact (type-II) have negative εNd (t) values (–4.97 to –0.90). In contrast, predominantly positive εNd(t) values (–0.84 to +5.40) are common in the remaining samples (type-I). The strongly positive δ56Fe values indicate a low degree of partial oxidation of Fe(II), which, combined with the pronounced positive Eu anomalies and the absence of Ce anomalies, hint towards that the deposition occurred mainly on a deep-sea environment with intense hydrothermal activity under anoxic and suboxic conditions, distal to continental landmasses. Locally, considerable oxygen was probably present in the ancient ocean's water masses, which led to the precipitation of BIFs.

Simultaneous Anodic and Cathodic Exfoliation of Graphite Electrodes in an Aqueous Solution of Inorganic Salt

AbstractElectrochemical exfoliation of graphite offers a scalable and efficient approach to synthesise graphene nanomaterials. This process is commonly performed either anodically or cathodically, whereas simultaneous dual processes offer an attractive energy efficient means to produce graphene materials with tuneable properties. Here, we demonstrate a simple electro synthetic approach to produce graphene simultaneously from both a graphite anode and a graphite cathode in K2SO4 aqueous solution. Graphite exfoliation was facilitated by employing 0.5 M K2SO4 as an electrolyte at 10 V, where efficient exfoliation simultaneously occurs at graphite foils serving as both anode and cathode. The anodically exfoliated graphene has a high defect density (ID/IG=0.58) and higher degree of oxidation (C/O=11.36), in comparison to graphene produced at cathode having a lower defect density (ID/IG=0.06) and a low oxidation degree (C/O=31.68). The usage of aqueous solution for scalable and efficient concurrent‐dual electrochemical exfoliation of graphite electrodes will facilitate the development of large‐scale production of graphene.

Repetitively pulsed nanosecond discharge plasma decay in propane–oxygen gas mixture in the presence of a heating electric field

Plasma decay in the afterglow of a repetitively pulsed nanosecond discharge in a stoichiometric propane–oxygen mixture was experimentally investigated when a weak heating DC electric field was applied and in its absence. The discharge was ignited at room gas temperature and a pressure of 1–2 Torr and was characterized by low specific energy inputs (<0.004 eV per molecule in one pulse). Using microwave interferometry, the temporal evolution of the electron density during plasma decay was studied, and the effective recombination coefficients were obtained from data processing. It was shown that the rate of plasma decay behaved in a non-monotonic manner with increasing degree of propane oxidation; at first the decay rate grew, then passed through a maximum, fell and saturated in the limit of a large (~2000) number of pulses. In this limit, the effect of the heating DC electric field on the plasma decay decreased with approaching chemical equilibrium. Numerical simulation of the observed effects was performed for low and high oxidation degrees of propane taking into account changes in the composition of positive ions in the plasma. Good agreement was obtained between measurements and calculations of the electron density during plasma decay in these cases. It was shown that the formation of cluster ions in the discharge afterglow plays a fundamental role. The plasma decay was controlled by electron recombination with hydrocarbon cluster ion at low oxidation degree of propane and with water cluster (hydrated) ions at high oxidation degree. A hypothesis was proposed to explain the observed nonmonotonic behavior of the plasma decay rate with an increase in the propane oxidation in the discharge, based on the formation of hydrated hydrocarbon ions CxHy+(H2O)k at moderate oxidation degrees.

Interface adjustment between poly(ethylene terephthalate) and graphene oxide in order to enhance mechanical and thermal properties of nanocomposites

AbstractThere is great interest in the use of graphene and derivatives in the production of polymer nanocomposites as it provides improvements in the properties of the materials to which they are associated. Such improvements depend heavily on filler dispersion and the interaction between the nanomaterials and the matrix. This work aimed to study the compatibility of graphene oxide (GO) with a poly(ethylene terephthalate) matrix. For this, graphite was modified using Hummers method, using reaction times of 3 and 6 h. The obtained GO was functionalized with amine, amide, and magnetite groups (FGO). The effects of the oxidation degree, functionalization and concentration of the nanofillers on the dispersion and consequently on the properties of the polymer nanocomposites were evaluated. The nanocomposites were synthesized by the solid–solid deposition method followed by the melt mixing technique. It was observed that lower concentrations of nanofiller associated with the lower degree of oxidation and functionalization improved the interaction of the nanofillers with the matrix, which resulted in better mechanical properties under tensile stresses for strain at break, maximum stress, Young's modulus and toughness. It was also observed that the glass transition and crystallization of nanocomposites increased due to a nucleating effect of the nanofillers.

Effects of Particle Size on the Microstructure and Mechanical Properties of HVAF-Sprayed Al-Based Quasicrystalline Coatings

To obtain dense Al-based quasicrystalline (QC) coatings with high content of quasicrystal phase, the QCs were deposited by the high-velocity air fuel spray process with different feedstock powder sizes. The phase composition, microstructure, chemical composition, tribological, and mechanical properties of the coatings were analyzed using x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray spectroscopy, a pin-on-disk wear tester, and a nanohardness tester. The results indicated that smaller particle sizes produced denser structures with lower coating porosities, while the coarser powder helped maintain the desired quasicrystalline phase. In addition, the coatings sprayed with coarser powders exhibited a lower sensitivity to the sliding velocity due to a stronger bonding strength between the splats and a lower oxidation degree. The coating first exhibited abrasive wear coupled with oxidative wear, which was then converted to delamination, abrasive wear, and intensified oxidative wear.

Tunable graphdiyne for DNA surface adsorption: affinities, displacement, and applications for fluorescence sensing.

Graphdiyne (GDY) adsorbed DNA probes have been used as a fluorescent sensing platform, but topics including DNA adsorption affinities, DNA probe displacement, and fluorescence quenching ability were rarely researched. Herein, the adsorption affinity of single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) on a tremella-like GDY was tuned by modulating the surface chemistry of GDY. The fluorescence quenching ability of GDY with different oxidation degrees was compared. The nonspecific displacement of DNA probes on GDY was studied. Under the same concentrations, GDY with low oxidation degree exhibited stronger adsorption affinity and higher adsorption capacity to both ssDNA and dsDNA than highly oxidized GDY. DNA adsorbed on low-oxidized GDY was more resistant to displacement by other DNAs. Protein showed strong interaction with different GDY and could displace DNA probes on GDY. Based on these findings, an ideal GDY with proper oxidation degree, exhibiting high surface affinity for ssDNA and low affinity for dsDNA, was used as scavenger of redundant ssDNA fluorescent probe in an enzyme-assisted amplification system for sensitive ochratoxin (OTA) detection. This study has enhanced our fundamental understanding of DNA adsorption by GDY. It also provided a rational way to apply GDY for fluorescence sensing in a complicated system.

Increasing reaction time in Hummers’ method towards well exfoliated graphene oxide of low oxidation degree

Graphene oxide (GO) has been synthesized by a modification of the Hummers’ method using different times of reaction of 30, 60, 120, 300 and 540 min while maintaining all other parameters constant and avoiding aggressive posttreatments such as sonication and strong agitation that are known to affect the chemical and structural integrity of the flakes. The morphology of the obtained flakes has been investigated by optical and electron microscopies. Chemical properties of the GOs have been determined by TGA, XRD, Raman, XPS and EDS. The degree of exfoliation strongly increased with the reaction time, while no significant differences were found between the GOs in terms of their chemistry. Thus, we demonstrate that increasing reaction time is enough for the obtention of large-sized and well-exfoliated GO flakes, while maintaining a chemical richness that would be hindered by aggressive exfoliation techniques.

Reduction of Electrochemically Exfoliated Graphene Films for High-Performance Electromagnetic Interference Shielding.

Two-dimensional graphene is of great interest for electromagnetic interference (EMI) shielding owing to its inherent electrical conductivity, lightweight, and excellent mechanical flexibility even at minor thicknesses. However, the complex synthesis and quality-control difficulties limit its application. In this study, we demonstrate that electrochemically exfoliated graphene (EEG) with post-reduction treatment is a promising candidate for lightweight EMI shielding materials. A facile electrochemical exfoliation approach produces a high-quality multilayer graphene with a high electrical conductivity of ∼600 S cm-1, owing to its low degree of oxidation. The reduction of EEG by three different methods, including chemical, thermal, and microwave treatments, causes the removal of surface functional groups as well as significant changes in the microstructure of the final films. The reduced graphene films by microwaves, which are driven by the improved electrical conductivity and large volume expansion, exhibit an EMI shielding effectiveness of 108 dB at a thickness of 125 μm, one of the largest EMI shielding values ever reported for graphene at comparable thicknesses.

Oxidation degree dependent adsorption of ssDNA onto graphene-based surface* *Project supported by the National Natural Science Foundation of China (Grant Nos. 11305237 and 11974366), the Fundamental Research Funds for the Central Universities, China, the Natural Science Foundation of Shanghai, China (Grant No. 19ZR1463200), and the Key Research Program of Chinese Academy of Sciences (Grant No. QYZDJ-SSW-SLH053).

DNA/GO composite plays a significant role in the research field of biotechnology and nanotechnology, and attracts a great deal of interest. However, it is still unclear how the oxidation degree of the graphene-based surface affects the adsorption process of single-strand DNA (ssDNA). In this paper, based on the molecular dynamics simulations, we find that ssDNA molecule is absorbed on the GO surface in the most stable state with the oxidation degree around 15%. The microscopic mechanism is attributed to the van Der Walls and the electrostatic interactions between the ssDNA molecule and the graphene-based surface, which is accompanied with the π–π stacking and hydrogen bond formation. The number of π–π stacking between ssDNA and GO reaches the maximum value when the oxidation degree is around 15% among all the GO surfaces. Our simulation results also reveal the coexistence of stretched and curved configurations as well as the adsorption orientation of ssDNA on the GO surface. Furthermore, it is found that the absorbed ssDNA molecules are more likely to move on the graphene-based surface of low oxidation degree, especially on pristine graphene. Our work provides the physics picture of ssDNA’s physisorption dynamics onto graphene-based surface and it is helpful in designing DNA/GO nanomaterials.

Anoxygenic photosynthesis linked to Neoarchean iron formations in Carajás (Brazil).

Microbial activity is often invoked as a direct or indirect contributor to the precipitation of ancient chemical sedimentary rocks such as Precambrian iron formations (IFs). Determining a specific metabolic pathway from the geological record remains a challenge, however, due to a lack of constraints on the initial conditions and microbially induced redox reactions involved in the formation of iron oxides. Thus, there is ongoing debate concerning the role of photoferrotrophy, that is the process by which inorganic carbon is fixed into organic matter using light as an energy source and Fe(II) as an electron donor, in the deposition of IFs. Here, we examine ~2.74-Ga-old Neoarchean IFs and associated carbonates from the Carajás Mineral Province, Brazil, to reconstruct redox conditions and to infer the oxidizing mechanism that allowed one of the world's largest iron deposits to form. The absence of cerium (Ce) anomalies reveals that conditions were pervasively anoxic during IF deposition, while unprecedented europium (Eu) anomalies imply that Fe was supplied by intense hydrothermal activity. A positive and homogeneous Fe isotopic signal in space and time in these IFs indicates a low degree of partial oxidation of Fe(II), which, combined with the presence of 13 C-depleted organic matter, points to a photoautotrophic metabolic driver. Collectively, our results argue in favor of reducing conditions during IF deposition and suggest anoxygenic photosynthesis as the most plausible mechanism responsible for Fe oxidation in the Carajás Basin.

Preparation of High Stability Graphene Oxide/Zinc Oxide Composite Membrane via Vacuum Filtration for Separation of Methylene Blue from Aqueous Solution

AbstractIn the present work, an excellent stable low graphene oxide/zinc oxide (LGO‐ZnO) composite membrane based on LGO nanosheets and ZnO nanonods has been successfully synthesized by vacuum filtration. The resultant graphene oxide nanosheet with a low degree of oxidation (LGO) was successfully prepared with the C/O ratio of 4.8 after stripped and oxidized. Importantly, the characterization results also demonstrated that ZnO nanorods were successfully intercalated into adjacent LGO nanosheets, rendering enlarged mass transfer channels, elevating hydration capacity and creating hierarchical nanostructures of membrane surfaces. Meanwhile, the stability of LGO‐ZnO composite membrane was enhanced obviously due to intercalation of ZnO nanorods, which was much more stable than that of LGO in aqueous solution. And it also exhibited outstanding permeation and separation performance for the water and various dyes solution system (with different concentration, volume or dye species), respectively. Accordingly, the permeate fluxes exhibited a drastic increase from 73 L/m2/h for LGO membrane to 1313 L/m2/h for LGO‐ZnO membrane. All the above results suggested that LGO‐ZnO membrane with high stability, high water permeability and favorable separation efficiency could be used as the great prospects membrane materials in separation of dyes from aqueous solution.

Thermal Conductivity of Graphene Oxide: A Molecular Dynamics Study

The thermal properties of graphene oxide containing hydroxyl and epoxy functional groups were studied using non-equilibrium molecular dynamics to understand the thermal transport phenomena involved and the structure factors limiting heat conduction. Estimates were given in terms of phonon mean free paths for the reduction in thermal conductivity by interior defects due to scattering. The mechanism of phonon transport in the graphene oxide was discussed. The results indicated that the degree of oxidation can significantly affect the thermal performance of graphene oxide. A low degree of oxidation is necessary to enhance the phonon transport properties of graphene oxide and reduce the probability of phonon-defect scattering. Phonon transport in graphene oxide with a high degree of oxidation is governed by the mean free path of phonons associated with scattering from interior defects. Oxygen-containing functional groups can adversely affect performance and reduce the efficiency of phonon transport in graphene oxide due to phonon mean free paths limited mainly by interior defects. The calculated intrinsic thermal conductivity of graphene oxide at room temperature is about 72 W/(m K) with an oxidation degree of 0.35 and about 670 W/(m K) with an oxidation degree of 0.05. The phonon mean free path decreases with increasing the degree of oxidation due to enhanced phonon-defect scattering, making the thermal conductivity very sensitive to the concentration of oxygen-containing functional groups.

High‐yield water‐phase exfoliated few‐defect graphene for high performance polymer nanocomposites

AbstractApplication of graphene requires a high‐yield, low‐cost, scalable production method, but it remains highly challenging. We here report a water‐phase technique to produce few‐defect graphene nanosheets (FGS) with a high exfoliation yield (92%), based on the chemically expanded graphite with ultrahigh specific surface areas, and demonstrate the application in graphene‐polymer nanocomposites. The exfoliated FGS has low degree of oxidation and preserves good mechanical and electrical properties, revealing promising potential for improving comprehensive properties of polymer composites. When 0.5 wt% FGS was incorporated to poly(methyl methacrylate) (PMMA), the 5% weight loss temperature and storage modulus increase by 87°C and 21%, respectively, relative to the neat polymer. With increasing the content of FGS to 4.6 wt%, the glass transition temperature of the composite increases by 25°C. In addition, the composites show a percolation threshold as low as 0.25 vol% and excellent electrical conductivity (50 S/m for 2.7 vol% FGS‐PMMA composite).

Laser Assisted Solution Synthesis of High Performance Graphene Supported Electrocatalysts

AbstractSimple, yet versatile, methods to functionalize graphene flakes with metal (oxide) nanoparticles are in demand, particularly for the development of advanced catalysts. Herein, based on light‐induced electrochemistry, a laser‐assisted, continuous, solution route for the simultaneous reduction and modification of graphene oxide with catalytic nanoparticles is reported. Electrochemical graphene oxide (EGO) is used as starting material and electron–hole pair source due to its low degree of oxidation, which imparts structural integrity and an ability to withstand photodegradation. Simply illuminating a solution stream containing EGO and metal salt (e.g., H2PtCl6 or RuCl3) with a 248 nm wavelength laser produces reduced EGO (rEGO, oxygen content 4.0 at%) flakes, decorated with Pt (≈2.0 nm) or RuO2 (≈2.8 nm) nanoparticles. The RuO2–rEGO flakes exhibit superior catalytic activity for the oxygen evolution reaction, requiring a small overpotential of 225 mV to reach a current density of 10 mA cm−2. The Pt–rEGO flakes (10.2 wt% of Pt) show enhanced mass activity for the hydrogen evolution reaction, and similar performance for oxygen reduction reaction compared to a commercial 20 wt% Pt/C catalyst. This simple production method is also used to deposit PtPd alloy and MnOx nanoparticles on rEGO, demonstrating its versatility in synthesizing functional nanoparticle‐modified graphene materials.

Comprehensive evaluation of dissolved organic matter molecular transformation in municipal solid waste incineration leachate

Transformations of the molecular compositions of dissolved organic matter (DOM) in incineration leachate (IL) were investigated. Results revealed that DOM in IL had a lower oxidation degree than that in mature MSW landfill leachate (LL). Moreover, aliphatic compounds (2.0 ≥ H/C ≥ 1.5) having the highest bioavailability were the most abundant type of DOM in IL, making IL significantly more biodegradable than LL. Under microbial actions, etc., DOM composed of phenolic compounds (aromaticity index (AI) ≤ 0.50 and H/C < 1.5), polyphenols (0.66 ≥ AI > 0.50) and polycyclic aromatics (AI > 0.66) in MBR-treated effluents were enriched and more diverse than in the untreated leachates. Nanofiltration (NF) dramatically lowered the relative abundances of phenolic compounds, polyphenols and polycyclic aromatics in effluent generated by treatment of IL in a MBR. Although the concentration of DOM in NF effluent was comparatively low, the DOM compositions in the resulting NF concentrate were nearly identical to those in MBR effluent, but were more complex than those in an international standard DOM due to a higher content of CHOS and CHONS heteroatomic compounds. Particularly, coagulation in conjunction with ozone/hydrogen peroxide oxidation process were dramatically reduced most polyphenols and polycyclic aromatics from the NF concentrate.

Scalable Fabrication of Carbon Nanomaterials by Electrochemical Dual-Electrode Exfoliation of Graphite in Hydroxide Molten Salt

Simultaneous electroexfoliation of graphite on both cathode and anode in molten NaOH–KOH was proposed and found to be a feasible method for the mass production of carbon nanomaterials. During this electrolysis process, alkaline cations and hydroxide ions were intercalated into the bulk graphite and then discharged to generate alkaline metals and hydrogen at the cathode, and oxygen at the anode. The simultaneous intercalation on both electrodes and the escape of gas enhanced the exfoliation efficiency, leading to a high production rate of nanostructured carbon exceeding 26.9 g h–1. The four to seven layers of graphene nanosheets with negligible defect (ID/IG = 0.079) and low oxidation degree (C/O ratio = 20.32) were obtained through cathodic exfoliation, while the corresponding anodic exfoliation products featured more oxygen-containing functional groups (7.59%). This introduced method was beneficial for the mass production of carbon materials in a highly efficient way.

Speciation and conversion of carbon and nitrogen in young landfill leachate during anaerobic biological pretreatment

There is an increasing need for landfill leachate pretreatment prior to discharge to wastewater treatment plants due to increasingly stringent sewer discharge limits. Lab-scale tests have shown that the anaerobic biological processes can effectively remove chemical oxygen demand and dissolved organic carbon from landfill leachate. Our work expands the knowledge in anaerobic leachate pretreatment by systematically studying the conversion of carbon and nitrogen species, particularly their recalcitrant fractions in a submerged anaerobic biofilm reactor using real-world leachate from a typical young municipal solid waste landfill. After reaching steady state, the reactor removed 41.7% of the fulvic acids (i.e., 1290 mg C/L). While compounds with a low degree of oxidation (O:C < 0.2) and compounds with a low degree of saturation (H:C < 1) were removed, compounds that were more oxidized (O:C > 0.2) and more saturated (H:C > 1) were produced. At steady state, 98% of recalcitrant dissolved organic nitrogen (i.e., rDON = 222 mg N/L) was removed. Compared to the DON in the raw leachate, the produced DON in the pre-treated leachate were more oxidized (O:C > 0.35) and more bioavailable (N:C > 0.07). The submerged anaerobic biofilm reactor may be an efficient leachate pretreatment method if rDON removal is needed.

Mixing of graphene nanoplatelets with magnesium alloy powders by electrostatic adsorption

Mg matrix composites reinforced by graphene nanoplatelets (GNPs) offers an efficient approach for improving the mechanical properties of Mg alloys. Unfortunately, the poor uniform dispersion of GNPs into Mg matrix vastly restricts their development. In addition, surface oxidation of Mg alloy powders is always serious. To alleviate these issues, pickling and surface modification technologies of ZK61 Mg alloy powders and mixing process with GNPs have been investigated. The results show that ZK61 alloy powders with smooth surface and low degree of oxidation can be obtained after being simultaneously mechanically stirred and ultrasonically treated for 30 min in a 0.2 vol% HF ethanol solution. They were then rinsed and dried, and modified by 0.3% wt% cetyl trimethyl ammonium bromide to carry a positive charge. Subsequently, GNPs ethanol suspension was poured into the modified ZK61 alloy powders solution and mechanically stirred for 10 min, and then a powder mixture that GNPs randomly attached on the Mg powders was obtained after drying.XPS analysis reveals that GNPs were adsorbed on the surfaces of the modified Mg powders by the mechanism of electrostatic adsorption. The achieved method for preparing GNPs/ZK61 alloy mixture powders provides a new strategy for fabricating Mg matrix composites reinforced by uniformly distributed GNPs.