Synthesis Of Composite Materials Research Articles

Synthesis and Properties of Polystyrene Composite Material with Hazelnut Shells.

In this study we evaluated the potential use of hazelnut shell powder in the production of a composite material. Polystyrene was used as a polymer matrix. This work presents the results of modifying hazelnut powder particles to create a polystyrene shell on their surfaces. Modification of the filler increased its contact angle wetted with water from θ=60.16±1.03° to θ=87.02±1.10°. Composite materials containing from 10 to 50 wt.% of modified hazelnut shell powder were prepared and studied. As a result of the experiments, it was found that the composites have optimal physical, mechanical, and operational properties at the following ratio: polystyrene 60-80 wt.%, modified hazelnut shell powder 20-40 wt.%. If the introduction of polystyrene was more than 90 wt.%, the flexural strength and Vickers hardness were quite low at the load of 200 g, and accordingly, the durability of such materials was not satisfactory. These samples are characterized by small percentages of hazelnut shells; therefore, the resulting material will be of pale, unsaturated color. The upper limit of the working temperature range for the composite lies between 265.0-376.0 °C, depending on the percentage of the hazelnut shell powder filling.

Photocatalytic Degradation of Ciprofloxacin with Supramolecular Materials Consisting of Nitrogenous Organic Cations and Metal Salts

The design and synthesis of composite materials with new structures/properties have important practical significance for the degradation of organic pollutants in aquatic environments. On this basis, five new supramolecular materials {[L1]2·[Cu4I8]}(1), {[L1]2·[Ag4I8]}(2), {[L2]·[ZnBr4]}(3), {[L3]2·[AgI5]}(4), {[L3]·[CdBr3Cl]}(5) were synthesized by introducing an amino group into a series of nitrogen-containing cationic ligands (L1–L3) through the reaction of polybromomethylbenzene with 4-aminopyridine. The degradation effect of catalysts 1–5 on ciprofloxacin (CIP) under visible light was studied using their potential catalytic properties. The results showed that compounds 1 and 4 had better degradation effects compared to other compounds. Moreover, compounds 1 and 4 were proved to be excellent catalysts for the photocatalytic degradation of CIP with cyclic experiments. Through further exploration, it was found that neutral conditions and 20 mg compound dosage were more conducive to the photodegradation of CIP by the compound. Through free radical capture experiments, it was found that ·OH played a major role in the photodegradation of CIP.

Hydrothermal Synthesis of Special Cubic Form MnO2 and MnCO3 Composite Material for Zinc Ion Battery and its Electrochemical Performance Test

In this paper, the aqueous zinc ion battery cathode material composed of manganese dioxide and manganese carbonate were synthesized by hydrothermal method. By optimizing the temperature and time in both hydrothermal and calcination process, the optimal synthesis conditions were discovered. Then, in order to survey and analysis the characteristics of the material, XRD, SEM, EDS and XPS tests were conducted. It can be seen from XRD test that the main crystal structure is MnO2 and MnCO3, and no other obvious impurity peaks are found. In the SEM test, it can be seen that the main shape of the material is regular cube, and there is triangular pyramidal bulge on the surface of the cube, which can increase the surface area of the material. As can be seen from EDS and element distribution diagram, Mn, O and C elements are evenly distributed. The XPS test shows that the valence states of the synthesized materials are consistent with those of MnO2 and MnCO3. According to the infrared test and Raman test, the characteristic peak vibration of the synthesized material is also consistent with those of MnO2 and MnCO3, indicating that the composite of MnO2 and MnCO3 with high electrochemical stability has been synthesized by hydrothermal method.

Significantly enhanced performance of Li-storage via in-situ oxidation of silicon particles by zinc oxide

The synthesis of Si-based composite material can be realized via the reduction of ZnO by excess Si during ball milling. X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy analysis confirmed the presence of the reacted products Zn and SiOx (0 <x < 2) in the Si matrix. The composite material was coated with carbon by a high-temperature carburizing process. The carbon-coated composite material shows excellent cycling stability at 0.2 C by demonstrating a capacity retention rate of 78.05 % after 300 cycles with a charging-specific capacity of 697 mA h/g. These results indicate that the nanocrystalline Zn and amorphous SiOx products from the solid-state reaction of cheap Si and ZnO are very effective in improving the cycling stability of Si-based composite material.

Synthesis of B&lt;sub&gt;4&lt;/sub&gt;C–TiB&lt;sub&gt;2&lt;/sub&gt; composition powder mixtures by carbidobor reduction using nanofibrous carbon for ceramic fabrication

The results of the researching process of obtaining composition powder material B4C–TiB2 by carbide reduction of titanium dioxide, using carbon reducing agent – carbon nanofibers, are presented. Furthermore, the results of studying of some properties of ceramics made using the synthesized powder are presented. The synthesis of composite materials was carried out in an induction crucible furnace for 20 min in the temperature range of 1200–1900 °C in an argon atmosphere. It has been established that the optimum temperature of the synthesis is 1650 °C, irrespective of the batch composition. The characteristics of the composite powders containing 10–30 mol. % of the TiB2 phase have been studied. X-ray electron microscopy has revealed that the particles of the powder are predominantly aggregated. There are two peaks in the particle size distribution histograms. The part of the histogram with a smaller particle size mainly characterizes the B4C phase. The part of the histogram with a larger particle size characterizes the TiB2 phase. The average particle size of the B4C phase is in the range of 5.3–5.5 µm, and that of the TiB2 phase is in the range of 33.6–41.9 µm. The average size of 50 % of composite powder’s particles for these contents does not exceed 13.4 μm. The surface area of the samples does not exceed 5 m2/g. The oxidation of the composite powder materials by atmospheric oxygen begins at a temperature of approximately 500 °C. At the same time, when the temperature reaches 1000 °C, no more than 45 wt. % of the studied powders is oxidized. Ceramics made with the synthesized powder mixture B4C + 30 mol. % TiB2 by hot pressing has shown rather high values of relative density (99.0±1.1 %) and fracture toughness (5.0±0.2 MPa∙m0.5).

Synthesis and Investigation of the Properties of Biphasic Hybrid Composites Based on Bentonite, Copper Hexacyanoferrate, Acrylamide and Acrylic Acid Hydrogel.

This article presents a study of the synthesis and characterization of new biphasic hybrid composite materials consisting of intercalated complexes (ICC) of natural mineral bentonite with copper hexaferrocyanide (phase I), which are incorporated into the bulk of the polymer matrix (phase II). It has been established that the sequential modification of bentonite with copper hexaferrocyanide and introduction of acrylamide and acrylic acid cross-linked copolymers into its volume by means of in situ polymerization promote the formation of a heterogeneous porous structure in the resulting hybrid material. The sorption abilities of prepared hybrid composite toward radionuclides of liquid radioactive waste (LRW) have been studied, and the mechanism for binding radionuclide metal ions with the components of the hybrid composition have been described.

Ion exchange derived nano-disperse metal oxides for high-performance lithium ion battery

Nano-structuring is the most optimized strategy for the kinetics acceleration of electrode materials in addressing the problems such as sluggish ion diffusion, poor electric conduction and liable pulverization. However, the complicated de-sizing methods are not preferable in future scale-up attempts, and the aggregation still needs to be solved. Herein, a facial ion-exchange/carbonization strategy is developed by tutoring the dispersion of metal ions with strong ionic interaction within resin framework, and nano-disperse of metal/metal-oxide particles (denoted as MOx) are in-situ implanted in hierarchical porous graphic carbon (HPGC). The HPGC can acts as a conductive and robust framework to anchor the MOx, while the nano-dispersed MOx can further propel the kinetics and alleviate the stress during cycling. We demonstrated the concept of this strategy via Fe3O4 @HPGC and Co3O4 @HPGC as representatives, both of which show superior rate capability (797.8 mAh g−1 for Co3O4 @HPGC at 5 A g−1) with long cycling stability, and high areal capacity (4.65 mAh cm−2 for Co3O4 @HPGC). With the industrial raw material of resin, the low cost and feasible method, this strategy can be potential candidate for the scalable synthesis of various carbon-hybridized composite materials.

Formation of the Transition Zone &amp;quot;Matrix Alloy - Reinforcing Granules&amp;quot; in the Process of Solid-Liquid Synthesis of Composite Material

Casted composite materials have found certain application in mechanical engineering. Their advantages are lower cost due to the use of casting technology (solid-liquid synthesis), absence of any restriction on the shape and weight of parts. It is known that the transition zone between the matrix alloy and reinforcing phase plays an important role on the level of mechanical properties of cast composites. So, the aim of the study is investigations of transition zone formation during the infiltration of matrix alloy into the frame formed by the reinforcing phase. Copper based alloy was used as a matrix alloy and cast-iron granules were used as a reinforcing phase. Cast composite materials have been exposed for different time during the synthesis. Specimens were studied using electron microscopy. Results on the concentration distribution of main elements (Si, Fe, Cu) in a transition zone are presented. It is shown that the formation of transition zone starts during the infiltration process with further its growth during the exposition at the synthesis temperature. It is established that the formation of the transition zone takes place not only due to elements diffusion but as well due to the dissolution of granules of reinforcing phase. Experiments carried out allow establishing some peculiarities of the transition zone formation. To achieve required level of mechanical properties it is necessary to control the melt temperature and duration of the synthesis of cast composite materials.

Laser-induced in situ synthesis of nano-composite Co–Co3O4–rGO on paper: miniaturized biosensor for alkaline phosphatase detection

Recent progress in the in situ synthesise of various nanomaterials has gained tremendous interest and wide applications in various fields. For the first time to the best of our knowledge, this work reports a methodology of ultra-fast in situ synthesis of cobalt–cobalt oxide-reduced graphene oxide (Co−Co3O4−rGO (CC–rGO)) composite by laser ablation. The photothermal reduction technique was leveraged to develop the CC–rGO. For this, a low-cost 450 nm blue diode laser was irradiated onto a grade 1 filter paper in the presence of cobalt ions readily patterns the carbon matrix of paper to the composite material. Moreover, the variation of cobalt concentrations from 0.1–0.5 M led to structural and morphological changes. Standard techniques were adopted for thorough characterizations of developed sensor material for conductivity analysis, specific surface area, crystal-structural information, surface morphology, and chemical composition. The observed results were highly promoting towards the electrochemical sensing applications. Further, the developed sensor was found to be highly selective toward detecting a vital bio analyte alkaline phosphatase (ALP). The sensors performance was highly significant in the linear range of 10–800 mU l−1 with a detection limit of 10.13 mU l−1. The sensors applicability was further validated in actual human serum samples via a recovery-based approach. In the future, the developed in situ material methodology can begin a rapid composite material synthesis at a larger scale.

Structure phase engineering strategy through acetic acid coupling to boost hydrogen evolution reaction performance of 2H phase MoS2 at wide pH range

The semiconductor phase molybdenum disulfide (2H-MoS2) with poor hydrogen evolution reaction (HER) performance restricts the further improvement of hydrogen production. Herein, an acetic acid coupled structure phase engineering (SPE) strategy is developed to synthesize a homogeneous and orderly cobalt molybdenum composite structure. The resulting CoS2/MoS2 complexes reveal excellent HER activity with a low overpotential of 80, 95, and 135 mV at 10 mA cm−2 in 0.5 M H2SO4, 1 M KOH, and 1 M PBS. Fourier transform infrared spectroscopy (FT-IR) and thermogravimetry mass spectrometry (TGA-MS) results illustrate that acetic acid is successfully coupled at the interface between CoS2 and MoS2. Results from density functional theory demonstrate that the π-π conjunction formed by acetic acid coupling can work as a bridge to help electrons transfer from cobalt to molybdenum. More importantly, the method can be extended to the synthesis of other composite materials with the similar structure.

Synthesis and Characteristics of Composite Material with a Plant-Based Filler

The article presents the results of synthesis of polymeric composite material based on epoxy binder and plant-based filler. Pre-dried and powdered wheat straw was used as a plant-based filler. The wheat straw content in the composite varied from 10 to 50 wt.%. Thermal, mechanical, and surface properties of composites depending on the wheat straw content were researched. In addition, the samples were studied for resistance to corrosive environments. The hydrophobic–hydrophilic surface balance of composites was evaluated, and their free surface energy was studied. Introduction of wheat straw in small amounts (up to 30 wt.%) increases bending strength of polymer from 18.65 ± 1.12 MPa to 22.61 ± 0.91 MPa; when the content is more than 40 wt.%, reduction of strength is observed. Even with a wheat straw powder content of 50 wt.%, the bending strength is 11.52 ± 1.03 MPa, which corresponds to the strength of the construction material. The upper limit of working temperature for the epoxy binder is 306 °C, and for the composite with the wheat straw content of 30 wt.%—264 °C. The surface of the pure polymer shows a hydrophilic character. The average value of the water wetting contact angle of the pure epoxy sample is 84.96 ± 9.03°. The introduction of 30 wt.% of wheat straw powder filler transforms the surface into hydrophobic one (average value of water wetting contact angle is 96.69 ± 5.71°). The developed composites can be applied in furniture production including tabletops or panels for floors. Future research will focus on expanding the types of plant-based fillers for polymer composites.

Special Issue on Metal-Based Composite Materials: Preparation, Structure, Properties and Applications

The Special Issue is aimed at analyzing modern trends and recent advances in the synthesis of new metal-based composite materials [...]

Novel Magnetic Composite Materials for Dental Structure Restoration Application.

In general, magnetic nanoparticles are not often used in dental applications due to some limitations of these materials, such as aggregation problems and low mechanical and chemical resistance but also esthetic problems due to their black color. Our research presents the synthesis of novel magnetic dental composite materials based on magnetic nanoparticles, functionalized and properly coated to overcome the limitations of using magnetic nanoparticles in dental applications. The composites were prepared using a preparation flow containing several integrated reaction steps used previously sequentially. An adequate and deep characterization of dental magnetic composites has been carried out in order to demonstrate that each limitation has been successfully overcome. It was proved that each component brings particular benefits in dental interventions: Fe3O4 nanoparticles have biocompatible, non-toxic properties and also antimicrobial effects; the SiO2 layer significantly increases the mechanical strength of the material; and the Ca(OH)2 layer initiates local calcification and significantly improves the color of the dental composite material. Due to magnetic properties, an innovative application approach on the tooth surface can be achieved under an external magnetic field, which, compared to conventional methods, has a major impact on reducing the occurrence of dental caries under filling materials as well as on reducing microfractures.

Study of the Possibility of Using Sol-Gel Technology to Obtain Magnetic Nanoparticles Based on Transition Metal Ferrites.

The article presents results for the magnetic nanoparticles sol-gel method synthesis of cobalt (II) ferrite and organic-inorganic composite materials based on it. The obtained materials were characterized using X-ray phase analysis, scanning and transmission electron microscopy, Scherrer, Brunauer-Emmett-Teller (BET) methods. A composite materials formation mechanism is proposed, which includes a gelation stage where transition element cation chelate complexes react with citric acid and subsequently decompose under heating. The fundamental possibility of obtaining an organo-inorganic composite material based on cobalt (II) ferrite and an organic carrier using the presented method has been proved. Composite materials formation is established to lead to a significant (5-9 times) increase in the sample surface area. Materials with a developed surface are formed: the surface area measured by the BET method is 83-143 m2/g. The resulting composite materials have sufficient magnetic properties to be mobile in a magnetic field. Consequently, wide possibilities for polyfunctional materials synthesis open up for various applications in medicine.

Design, Synthesis and Characterization of Hybrid Composite Materials

Polymer composites represent the platform materials of the 21st century, and they make up an important slice of the market for the production of modern materials [...]

Synthesis of ReB2-Al2O3 composite powders and chemical resistance of the products to moisture

Synthesis of composite material from the ReO2 + Al2O3 + Al + B2O3 mixture was carried out. Mixtures were annealed at 1150 °C for 1 h or in two-steps process at 1050 °C and 1150 °C for 4 h, in argon. Different B2O3/ReO2 molar ratios were adopted: 1.0; 1.3; 1.5; 1.8; 2.0; 2.3, 2.5; 2.8; 3.0. The TG/DTA analysis was performed for the synthesis of mixtures of different molar ratios. Produced materials were tested by XRD phase composition studies. In every mixtures, products consisted mainly of ReB2, Al2O3, Re7B3 and aluminum borides. The research was aimed at reducing the share of the Re7B3 phase. Increase of the B2O3/ReO2 molar ratio in the syntheses results in the formation of boromullite phases such as Al5BO9, Al18B4O33, Al4B2O9. XRD and XPS investigations were carried out after prolonged exposure to humidity. Materials produced at a molar ratio B2O3/ReO2 = 1 are characterized by greater resistance to water from moisture compared to other tested mixtures.

A novel in situ sample environment setup for combined small angle x-ray scattering (SAXS), wide-angle x-ray scattering (WAXS), and Fourier transform infrared spectrometer (FTIR) simultaneous measurement.

Developing the synchrotron radiation experiment method based on combined technology offers more information on the formation mechanism of new materials and their physical and chemical properties. In this study, a new small-angle x-ray scattering/ wide-angle x-ray scattering/ Fourier-transform infrared spectroscopy (SAXS/WAXS/FTIR) combined setup was established. Using this combined SAXS/WAXS/FTIR setup, x-ray and FTIR signals can be obtained simultaneously from the same sample. The in situ sample cell was designed to couple two FTIR optical paths for the attenuated total reflection and transmission modes, which greatly saved the time of adjusting and aligning the external infrared light path when switching between the two modes with good accuracy. A transistor-transistor logic circuit was used to trigger the synchronous acquisition from the IR and x-ray detectors. A special sample stage is designed, allowing access by the IR and x-ray with temperature and pressure control. The newly developed, combined setup can be used to observe the evolution of the microstructure during the synthesis of composite materials in real-time at both the atomic and molecular levels. The crystallization of polyvinylidene fluoride (PVDF) at different temperatures was observed. The time-dependent experimental data demonstrated the success of the in situ SAXS, WAXS, and FTIR study of the structural evolution, which is feasible to track the dynamic processes.

Synthesis and Characterization of New Composite Materials Based on Magnesium Phosphate Cement for Fluoride Retention.

In this research work, new composite materials based on magnesium phosphate cement (MPC) were developed to evaluate the retention of fluorine from wastewater. This material was prepared with dead burned magnesia oxide (MgO), ammonium dihydrogen phosphate (NH4H2PO4), and some retarding agents. We chose to synthesize with hydrogen peroxide instead of water; alumina and zeolite were also added to the cement. The obtained optimal conditions were studied and analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), BET, and thermogravimetric analysis (TGA). The adsorbents showed a strong ability to remove fluoride from contaminated water, and the best defluoridation capacity was evaluated as 2.21 mg/g for the H2O2 cement. Equilibrium modeling was performed, and the experimental data were presented according to the isotherms of Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich.

Synthesis and electrochemical characterization of electrospun biocompatible Poly (ε- caprolactone) and Polyaniline nanofiber composite electrode materials for various biosensing applications

Electrospun nanofibrous scaffolds have attracted extensive attention in biosensor applications. Typical structures were made using low molecular weight (Mw ∼ 10,000) Polycaprolactone (PCL) along with Polyaniline (Emeraldine salt) via the fiber production technique of electrospinning. The PCL/PANI nanocomposites were optimised at 14 wt% and 15 wt% for quality electrospinning conditions.The functional group’s identification, structural and morphological analyses and electrochemical studies of the nanocomposites were performed. The specific capacitance values Csp = 16.54F/kg (14 wt%) and 5.26F/kg (15 wt%) were calculated. The Cyclic voltammetric and Impedance spectroscopic studies along with a newly designed equivalent circuit, indicate the sensitive and fast responses of the PCL/PANI nanocomposite material, with unique porous structures developed within the material, provide a potential opportunity to develop into a sensitive sensor electrode material.

Bi nanoparticles confined in N,S co-doped carbon nanoribbons with excellent rate performance for sodium-ion batteries.

Bismuth (Bi) has emerged as a promising candidate for sodium-ion battery anodes because of its unique layered crystal structure, superior volumetric capacity, and high theoretical gravimetric capacity. However, the large volume expansion and severe aggregation of Bi during the alloying/dealloying reactions are extremely detrimental to cycling stability, which seriously hinders its practical application. To overcome these issues, we propose an effective synthesis of composite materials, encapsulating Bi nanoparticles in N,S co-doped carbon nanoribbons and composites with carbon nanotubes (N,S-C@Bi/CNT), using Bi2S3 nanobelts as templates. The uniform distribution of Bi nanoparticles and the structure of carbon nanoribbons can reduce the diffusion path of ions/electrons, efficiently buffer the large volume change and prevent Bi from aggregating during cycles. As expected, the N,S-C@Bi/CNT electrode shows superior sodium storage performance in half cells, including a high specific capacity (345.3 mA h g-1 at 1.0 A g-1), long cycling stability (1000 cycles), and superior rate capability (336.0 mA h g-1 at 10.0 A g-1).