Nanocomposite Materials Research Articles

Mechanical properties of polymer composite films with ZnO nanoparticles synthesized in low-temperature plasma under ultrasonic cavitation

Abstract In this study, polymer nanocomposite materials consisting of the copolymer of ethylene and vinyl acetate as a matrix and nanoparticles of zinc oxide as a filler have been obtained and examined by physicochemical and mechanical methods. Zinc oxide nanoparticles used in this study were fabricated using the plasma discharge under the effect of intensive ultrasonic cavitation. To ensure that resulting nanocomposites will acquire homogeneous distribution of filler nanoparticles, solution technology was utilized followed by the melt compounding technique, and also nanoparticles treated and non-treated with ultrasound were applied. The fabricated samples of nanocomposite material films were examined by X-ray phase analysis, then X-ray fluorescence analysis as well as scanning electron microscopy. The differences between the samples were demonstrated: when the nanoparticles without ultrasonic treatment were used, the particles were found to be more strongly aggregated within the bulk of the composite material and the average size of particles was visually larger in comparison to the sample filled with nanoparticles subjected to ultrasonic action. Finally, studies of the tensile strength and relative deformation of the samples were carried out. From the results of mechanical tests, it can be seen that, according to both studied parameters, there is an optimal concentration of ZnO nanoparticles. For tensile strength, the highest result was obtained at a concentration of nanoparticles of 3%, and for the relative elongation to rupture of the sample, the highest value was achieved at a concentration of nanoparticles of 2%.

Synthesis of carbon nitride nanosheets with N vacancies boosted by S doping for photocatalytic efficient killing of E. coli under visible light

To address the problem of bacterial contamination in drinking water, we synthesized non-metallic photocatalysts for the inactivation of Escherichia coli in drinking water. In this paper, S-g-C3N4 (S-g-CN) composite nanomaterials were synthesized via a one-step calcination method. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and transmission electron microscopy (TEM) analyses confirmed the successful synthesis of S-g-CN with N vacancies. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy analyzed the layered morphology and chemical structure of g-C3N4 before and after modification. Optical characterization revealed significantly enhanced light absorption, electron-hole separation efficiency, and carrier mobility in the modified samples. Bactericidal assays demonstrated that under visible light, 0.3 % S-g-CN nanomaterials exhibited superior bactericidal effects against E. coli compared to unmodified g-C3N4. Furthermore, 0.3 % S-g-CN demonstrated excellent degradation of Rhodamine B (RhB) under various conditions (pollutant concentration, pH, and catalyst dosage). Recyclability studies over three cycles confirmed the catalyst's stability and reusability.

Bifunctional properties of Ag/α-Fe2O3/rGO nanocomposite for supercapacitor and electrochemical nitrate sensing using tetradodecyl ammonium nitrate as ion-selective membrane.

Noble metal nanoparticles incorporated in hybrid nanocomposites are considered as promising candidates for electrochemical applications owing to their physicochemical properties. In this work, we demonstrated the preparation of Fe2O3/rGO nanocomposite by hydrothermal method, followed by in situ Ag binding synthesis for the fabrication of hybrid nanocomposite (Ag/α-Fe2O3/rGO). The crystallographic structure of the hybrid nanocomposite is examined by X-ray diffraction (XRD) analysis which confirms the characteristics of Ag, Fe2O3, and rGO. The microscopic studies and energy-dispersive X-ray analysis (EDS) spectra confirmed the presence and formation of hybrid nanostructures. Raman analysis results further corroborate the formation of composite with significant D and G bands in Fe2O3/rGO and Ag/α-Fe2O3/rGO samples, which follow XRD results. Cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) studies were carried out to analyze the faradaic capacitor behavior. A specific capacitance of 209.09 F/g was observed by GCD studies for Ag/α-Fe2O3/rGO composites at a current density of 1 A/g, which exhibited good capacitance retention of 94% for 5000 cycles at 7 A/g. Furthermore, the Ag/α-Fe2O3/rGO electrode was used for the electrochemical detection of nitrate ions in soil by utilizing an ion-selective membrane over the surface of the Ag/α-Fe2O3/rGO electrode. The fabricated nanocomposite electrode showed a significant change in the peak current values with the concentration of nitrate in a linear range from 10 to 450μM with the sensitivity to be calculated 1.426 μA μM-1cm-2 and limit of detection (LOD) calculated to be 0.18μM. The reproducibility and interference studies showed a promising result to be utilized for detecting nitrate ions in soil and in real-time applications.

Fabrication of iron manganese oxide-reduced graphene oxide nanocomposite: A highly effective synergistic electrocatalyst for sensitive metronidazole detection

Efficient 2D-inorganic spinel perovskites nanostructure materials are used as potential candidates for highly sensitive detection of harmful substances present in the environment. In this regard, a facile one-pot hydrothermal synthesis was employed to fabricate nanocomposite material containing iron manganese oxide (FeMn2O4) decorated with reduced graphene oxide (rGO) which is used as an electrochemical detection of metronidazole (MTZ). The crystalline nature and structural insights of the as-synthesized FeMn2O4-rGO nanocomposite were established using various spectroscopic and electrochemical techniques. Distinctively FeMn2O4-rGO nanocomposite fashioned glassy carbon electrode (GCE) showed excellent linear range (0.01–512.2 μM), sensitivity (71.4 μA mM−1 cm−2), limit of detection (0.0129 μM), reproducibility, stability and resist-interference capability towards metronidazole (MTZ) antibiotic drug. In addition, the fabricated FeMn2O4-rGO/GCE electrochemical sensor exhibited a remarkable MTZ detection in spiked water as well as urine samples with better recovery percentages supporting its facile and feasible nature for environmental applications. The present work established the fabrication of FeMn2O4-rGO/GCE nanocomposite for effective determination of antibiotic drugs in real sample analysis.

Vaccinium corymbosum–Derived Carbon Dots and Anthocyanin‐Infused Gelatin Multifunctional Films for Smart Packaging Applications

ABSTRACTConsumers and food industry stakeholders have expressed great interest in using simple, non‐destructive and inexpensive methods to control/maintain or monitor the freshness of perishable foods. The idea of smart packaging has been introduced to address these requirements satisfactorily, revolutionizing conventional food packaging. Vaccinium corymbosum (VC)–based carbon dots (CDs) and anthocyanin were matrixed on gelatin (GEL) to fabricate smart packaging film. The VC biowaste–derived carbon dots (VC‐CDs) were characterized using photoluminescence, fluorescence spectrometry, FTIR, antibacterial/antioxidant potential, TEM and XPS analysis. Fabricated films were subjected to physico‐chemical, antioxidant and optical properties, SEM, TGA simulation and in vivo food model system. The VC‐CDs exhibited excellent functional properties like ultraviolet (UV) blocking and antibacterial properties. The reinforcement with 1.5% VC‐CDs and 6% VC anthocyanins (VCA) in the GEL polymer matrix improved UV blocking (> 189%) properties and showed potent antioxidant potential (> 164%) compared to the neat GEL film. In vivo food packaging (minced pork, fish and shrimp) with films has shown that indicator films work efficiently and non‐destructively and monitor real‐time freshness. The GEL/VC‐CDs/VCA‐based active and intelligent films are expected to be applied as multifunctional nanocomposite packaging materials that can indicate quality changes in real time, maintain quality and prolong the shelf life of packaged foods.

Synergistic Effects in BFO@NiCoS@CNT//AC Nanocomposite for High-Capacity Energy Storage Systems

Here, we synthesized a nanocomposite electrode material for high-performance asymmetric supercapacitor devices (ASCD) made of bismuth ferrite (BFO) nanocomposite and nickel cobalt sulfide with carbon nanotubes (NiCoS@CNT). To fabricate the BFO@NiCoS@CNT nanocomposite, a simple hydrothermal process was used. Electrochemical impedance spectroscopy, galvanostatic charge/discharge measurements, and cyclic voltammetry were used to evaluate the electrochemical experiments. At a scan speed of 5 mVs−1, the BFO@NiCoS@CNT nanocomposite exhibited a specific capacitance of 2890 Fg−1, surpassing pure BFO@NiCoS. Furthermore, the nanocomposite displayed excellent cyclic stability, retaining around 87.8% of its capacity retention even after 5000 cycles. Another notable property is its energy density (Ed) of 71 Whkg−1 at the power density (Pd) of 2400 Wkg−1. Based on these promising findings, BFO@NiCoS@CNT nanocomposite might be used to fabricate electrodes for high-performance hybrid supercapacitors. Our research indicates that this is the first report of a BFO@NiCoS@CNT nanocomposite used as an asymmetric supercapacitor.

Facile synthesis of novel bismuth oxide/bismuth molybdate nanocomposites as advanced anodes for high performance Li‐ion batteries

In this study, a novel nanocomposite material consisting of Bi2O3 and Bi2MoO6, named as Bi2O3@Bi2MoO6, was successfully fabricated by co-precipitation method in ethylene glycol solvent. Morphological analysis of the heat-treated sample at 400 °C for 12 h in Ar atmosphere (Bi2O3@Bi2MoO6 _400 °C) showed that it contained nano-sized particles of Bi2O3 and Bi2MoO6; in addition, an amorphous phase along with a crystalline structure was also observed. When used as an anode for Li-ion batteries (LIBs), Bi2O3@Bi2MoO6 _400 °C anode exhibits excellent electrochemical properties such as high Coulombic efficiency, high specific capacity, excellent capacity retention, and outstanding rate capacity. Specifically, the Bi2O3@Bi2MoO6 _400 °C anode presented a reversible capacity of 786 mAh g−1 at the beginning cycle at 0.1 A g−1 and retained about 90 % of the charging capacity value after 80 cycles. The advanced electrochemical properties of the nanocomposite anode are related to the combination of many aspects such as nanostructure, existence of amorphous phase, and pseudo-behaviour of metal-based components. The structural stability and electrochemical performance of the anode material, therefore, are improved. These results demonstrate Bi2O3@Bi2MoO6 _400 °C as a promising material for establishing high-performance LIB anodes.

Encapsulating Fe3O4 Nanoparticles and Carbon Dots in a Metal-Organic Framework for Magnetic Fluorescent Taggants.

Magnetic fluorescent composite nanomaterials have broad application prospects in the fields of biological imaging, anticounterfeiting identification, suspicious object tracking, and identification of latent fingerprints in forensic medicine. For an effective taggant, a clearly visible identifying mark is necessary to enable observers to capture labeling information quickly and accurately, even from a distance. The preparation method of magnetic fluorescent composite materials is complicated and usually needs different surface modification and assembly processes. The limited loading capacity of fluorescent materials also limits the fluorescence properties of the composite, so it is difficult to produce obvious fluorescence as a taggant to meet the requirements of visible labeling. In this study, a core-shell structure of a magnetic fluorescent composite was prepared by using the metal-organic framework ZIF-8 as the host of fluorescent materials and an encapsulation shell coated on the Fe3O4 nanoparticles. The porous ZIF-8 is beneficial for increasing the loading capacity of fluorescent materials to ensure the fluorescence performance of the composite materials. Further modification of the composite surface prevented the desorption of fluorescent materials from the pores of ZIF-8, enabling the samples to maintain good fluorescence properties even after multiple washing cycles. The preparation method is simple, rapid, and cost-effective, and the prepared magnetic fluorescent composite nanomaterial has high magnetic separation performance and fluorescence performance, making it a promising material for identification, marking, and tracking.

Molecular dynamics study of Gr(GO)/C-A-S-H composites at different temperatures: optimization of structural, dynamic and mechanical properties of civil engineering materials

In recent years, composites have been widely used in engineering fields, where nanomaterials such as graphene (Gr) and graphene oxide (GO) have potential advantages as interfacial modifiers in enhancing the properties of composites. However, the relationship between the interfacial structure and the mechanical properties of the nanocomposites is not clear, and the behavior of the composites may differ significantly at different temperatures. This study aims to investigate in depth the interfacial structure, dynamics, and mechanical properties of Gr, epoxy group-containing (-O) and hydroxyl group-containing (-OH) graphene oxide and calcium aluminosilicate hydrate (C-A-S-H) composites at different temperatures using molecular dynamics. The effect of nanomaterial composition on the interfacial chemical bonding network is revealed. The local chemical structures of bridging aluminum [Al(Q2b)] and interlayer aluminum (Alw) show different changes at different temperatures. Elevated temperature promotes the hydrolysis of interlayer water molecules to form hydroxyl groups, which affects the formation of chemical bonding networks.Al(Q2b) favors Gr and C-A-S-H linkages, whereas Alw favors GO and C-A-S-H bonding. Temperature changes lead to different chemical bonding connections and altered atomic motions. At the interface, Al atoms form a more stable chemical bonding network, which improves the interaction strength at the interface. Different composite models exhibited different mechanical properties at high temperatures and introducing epoxy and hydroxyl groups enhanced the plastic deformation of the composites. Structural analyses showed that temperature changes affected the molecular structure and interfacial bonding effects of the composites, which in turn affected the mechanical properties of the materials. At different temperatures, GO-O/C-A-S-H has higher tensile strength and Young's modulus, which can resist the degradation of performance caused by thermal expansion to a certain extent, and ensure the stability and safety of the structure, so it is more practical. These findings provide important insights to deepen the understanding of composite properties and have positive implications for future composite design and applications.

Amino Acid-Conjugated Polymer-Silver Bromide Nanocomposites for Eradicating Polymicrobial Biofilms and Treating Burn Wound Infections.

The rise in antimicrobial resistance, the increasing occurrence of bacterial, and fungal infections, and the challenges posed by polymicrobial biofilms necessitate the exploration of innovative therapeutic strategies. Silver-based antimicrobials have garnered attention for their broad-spectrum activity and multimodal mechanisms of action. However, their effectiveness against single-species or polymicrobial biofilms remains limited. In this study, we present the fabrication of polymer-silver bromide nanocomposites using amino acid conjugated polymers (ACPs) through a green and water-based in situ technique. The nanocomposite architecture facilitated prolonged and controlled release of the active components. Remarkably, the nanocomposites exhibited broad-spectrum activity against multidrug-resistant (MDR) human pathogenic bacteria (MIC = 2-16 μg/mL) and fungi (MIC = 1-8 μg/mL), while displaying no detectable toxicity to human erythrocytes (HC50 > 1024 μg/mL). In contrast to existing antimicrobials and silver-based therapies, the nanocomposite effectively eradicated bacterial, fungal, and polymicrobial biofilms, and prevented the development of microbial resistance due to their membrane-active properties. Furthermore, the lead polymer-silver bromide nanocomposite demonstrated a 99% reduction in the drug-resistant Pseudomonas aeruginosa burden in a murine model of burn wound infection, along with excellent in vivo biocompatibility.

Bio-nanocomposites: Innovative solutions for addressing issues in health, agriculture, energy and environmental domains

The extensive industrial use of plastics causes serious environmental problems. In order to solve this, scientists have concentrated on developing composites that are environmentally sustainable through the integration of nanofillers with bio-based components. These bio-nanocomposites, with significant potential in health, agriculture, energy, and environmental applications, offer a viable alternative to conventional plastics. In the field of medicine, bio-nanocomposites, owing to their unique properties and functionalities, find extensive applications in tissue culture, wound healing, and drug delivery. Also, bio-nanocomposites have the ability to support sustainable agriculture while enhancing crop yields. Additionally, due to their enhanced conductivity and environmentally beneficial components, bio-nanocomposites stimulate innovations in energy storage and renewable energy technology. Furthermore, the bio-nanocomposites provide environmentally friendly options for remediation and pollution management. This review explores the diverse applications of nanocomposite and bio-nanocomposite materials across healthcare, agriculture, energy storage and environment sectors and discusses strategies for enhancing their features to suit specific applications.

Effect of nanocomposite cementitious capillary crystalline waterproofing material on self-healing properties of cementitious composites

There are limited studies about the effect of nanocomposite cementitious capillary crystalline waterproofing material (CCCW) on the self-healing properties of cementitious materials in different environments. Compressive strength recovery ratio(CSRR) test, electrochemical impedance spectroscopy (EIS) test, and macroscopic cracks healing observation test were adopted to study the self-healing properties of pure mortar specimens, mortar specimens mixed with CCCW, and nanocomposite CCCW respectively under three kinds of curing conditions. The self-healing mechanism of nanocomposite CCCW was analyzed using thermogravimetric analysis and differential scanning calorimetry (TG-DSC), mercury intrusion porosimetry (MIP), and scanning electronic microscope and energy dispersive spectroscopy (SEM-EDS) techniques. It was found that the curing condition significantly influenced self-healing performance, with touching water curing condition having the highest impact, followed by soaking water curing condition and natural curing condition. Nanocomposite CCCW promoted the healing performance of damaged specimens and significantly increased the CSRR. Under touching water curing condition, the CSRRs of the mortar groups with 3% nano-SiO2, 3% nano-CaCO3, and 2% nano-MgO were 26.1%, 11.5%, and 8.6%, respectively, higher than the CSRR of the single-doped CCCW group. After 28 days of touching water curing, change in charge transfer resistance before and after specimen healing (∆Rct) of the groups with 3% dosage of nano-SiO2, 3% dosage of nano-CaCO3, and 2% dosage of nano-MgO were 5.2, 1.8, and 2.7 times, respectively, higher than that of the single-doped CCCW mortar group. Throughout the healing process, the addition of the three nanocomposite CCCWs accelerated the hydration reaction to generate C-S-H gel, CaCO3, Aft, etc., improved the internal pore structure, reduced the size of the most probable pore diameter (MPPD) of the mortar specimens, and ultimately promoted the self-healing properties of the cementitious materials.

Nitroxide radical conjugated ovalbumin theranostic nanosystem for enhanced dendritic cell-based immunotherapy and T1 magnetic resonance imaging

Melanoma, known for its aggressive metastatic nature, presents a formidable challenge in cancer treatment, where conventional therapies often fall short. This study introduces a pioneering approach utilizing metal-free nanosystem as tumor vaccines, spotlighting their potential in revolutionizing melanoma treatment. This work employed organic nitroxides, specifically 4-carboxy-TEMPO, in combination with chitosan (CS), to create a novel nanocomposite material - the CS-TEMPO-OVA nanovaccines. This composition not only improves biocompatibility and extends blood circulation time of TEMPO but also marks a significant departure from traditional gadolinium-based contrast agents in MRI technology, addressing safety concerns. CS-TEMPO-OVA nanovaccines demonstrate excellent biocompatibility at both the cellular and organoid level. They effectively stimulate bone marrow-derived dendritic cells (BMDCs), which in turn promote the maturation and activation of T cells. This ultimately leads to a strong production of essential cytokines. These nanovaccines serve a dual purpose as both therapeutic and preventive. By inducing an immune response, activating cytotoxic T cells, and promoting macrophage M1 polarization, they effectively inhibit melanoma growth and enhance survival in mouse models. When combined with αPD-1, the CS-TEMPO-OVA nanovaccines significantly bolster the infiltration of cytotoxic T lymphocytes (CTLs) within tumors, sparking a powerful systemic antitumor response that effectively curbs tumor metastasis. The ability of these nanovaccines to control both primary (subcutaneous) and metastatic B16-OVA tumors highlights their remarkable efficacy. Furthermore, the CS-TEMPO-OVA nanovaccine can be administered in vivo via both intravenous and intramuscular routes, both of which effectively enhance the T1 contrast of magnetic resonance imaging in tumor tissue. This study offers invaluable insights into the integrated application of these nanovaccines in both clinical diagnostics and treatment, marking a significant stride in cancer research and patient care.

New cellulose-polyacrylamide hydrogels containing nano-cerium oxide as new promising nanocomposite materials for biomedical applications

New cellulose-polyacrylamide hydrogels containing nano-cerium oxide as new promising nanocomposite materials for biomedical applications

Gelatin Assisted Cerium–Copper Sulfide Nanoparticles as Efficient Catalysts for the Photocatalytic Degradation of Malachite Green Oxalate Dye Under UV‐A Light

AbstractChemical, petroleum, and dyeing industries generate a wide variety of highly toxic organic wastes. The discharge of this wastewater into the river without treatment will spoil the entire aquatic system. The photocatalytic degradation of dyes/toxic chemicals is considered a favorable technology for industrial wastewater treatment. For this purpose, we have prepared an efficient nanocomposite material. The Gelatin assisted Cerium loaded CuS (Ge−Ce−CuS) nanocomposite was successfully synthesized by a simple hydrothermal method and characterized by BET, UV‐DRS, and PL measurements. The BET surface area of Ge−Ce−CuS (88.6 m2 g−1) is higher than bare CuS (66.0 m2 g‐1). DRS Confirms that the photo‐absorption of Ge−Ce−CuS nanocomposite significantly increases from the 570 nm range to the whole visible region. PL measurements confirm that the CuS loading suppresses electron‐hole recombination of Ge−Ce−CuS. The photocatalytic activity of Ge−Ce−CuS was investigated for the degradation of malachite green oxalate dye (MGO) in an aqueous solution using UV light. The influence of operational parameters such as the amount of photocatalyst, dye concentration, and initial pH on the photo mineralization of MGO dye has been analyzed and discussed. Slightly basic pH enhances the degradation. The mineralization of MGO dye has been confirmed by COD measurements. The intermediates formed during degradations were analyzed by GC‐MS, and a suitable degradation pathway was proposed. The catalyst is found to be reusable. The mechanism of degradation of MGO dye by Ge−Ce−CuS is also proposed.

Solar evaporation of liquid marbles with Fe3O4/CNT hybrid nanostructures

HypothesisThrough the rational design of nanomaterial composites, broadband light harvesting and good thermal insulation can be achieved simultaneously to improve the efficiency of water evaporation. ExperimentSolar evaporation experiments were carried out on liquid marbles (LMs) coated with Fe3O4 nanoparticles, carbon nanotubes (CNTs) and hybrid nanomaterials (Fe3O4/CNTs) with different mass ratios of 2:1, 1:1 and 1:2. FindingThe results showed that the mixture of Fe3O4/CNTs enhances the light harvesting ability and solar interfacial evaporation performance. Fe3O4/CNT-LM at the mass ratio of 2:1 case provides the highest evaporation rate of 11.03 μg/s, which is about 1.22 and 1.34 times higher than that of Fe3O4 and CNT, respectively. This high performance is mainly due to the synergistic effect between Fe3O4 nanoparticles and CNTs, as the hybrid nanostructure significantly improves the both photothermal conversion and heat localization capability. Numerical simulation further supports that the composite can concentrate the electromagnetic field and heat at the phase-change interface. This leads to a rapid evaporation of the boundary region. This study provides a novel approach to a three-dimensional interface by assembling nanomaterials on the drop surface to enhance evaporation, which may have far-reaching implications for seawater desalination.

Novel electrochemiluminescence sensing platform for ultrasensitive detection of malathion residue in tea based on SiO2NSs doped Luminol/AgNPs as a signal amplification strategy

To address the potential hazards of organophosphorus pesticides (OPs) residues in tea, an electrochemiluminescence (ECL) aptasensor based on functionalized nanomaterials was constructed in this work. Firstly, gold nanoparticles (AuNPs) were attached on the surface of multi-walled carbon nanotubes (MWCNTs) by the constant potential electrodeposition to form a compound, and it was utilized to provide excellent immobilization sites for complementary DNA (cDNA). Subsequently, composite nanomaterials were synthesized by a one-pot method with aminated Luminol/silver nanoparticles@silica nanospheres (NH2-Luminol/Ag@SiO2NSs). Finally, NH2-Luminol/Ag@SiO2NSs was combined with a malathion aptamer (Apt) to obtain signal probes (SPs) for the construction of an aptasensor. The aptasensor had a wide linear range (1×10−3-1×103 ng/mL) and a low limit of detection (LOD) (0.3×10−3 ng/mL). It had the virtues of high sensitivity, wonderful stability and excellent specificity, which could be used for the detection of malathion residue in tea. The work provides a proven way for the construction of a rapid and ultrasensitive aptasensor with low-cost.

Study of the influence of hybrid filler on the strain sensitivity of nanocomposite material

The reflector of spacecraft is in operation in an open and folded position, so an urgent task is to develop strain gauges that determine the position of the reflector. The paper presents a study of the influence of a hybrid filler on the value of the strain resistance coefficient of a flexible strain-resistive element made of a nanocomposite material and describes the technological process of its manufacture using the vacuum infusion method. As a hybrid filler, a composition was used containing an electrically conductive component (carbon nanotubes) and a solid component (silicon carbide), which promotes uniform distribution of the filler in the polymer matrix. Using the rotational rheometer, the content of carbon nanotubes (CNTs) was determined at which the limiting level of viscosity for impregnation of glass fiber with a binder is achieved. The distribution features of the filler in the nanocomposite material were studied using a scanning electron microscope at the Krasnoyarsk Regional Center for Collective Use of the Federal Research Center KSC SB RAS. In the course of the work, the influence of the content of the hybrid filler on the tensoresistive properties of the nanocomposite material was determined. The maximum values of the tensor resistance coefficient were observed at the initial stage of the study (stretching 0.05 %): with a stretch of 0.1 mm with a total length of 200 mm for samples of nanocomposite material with a SiC hybrid filler of 1, 5 and 10 % and is 38, 40 and 40 The tensoresistance coefficient of nanocomposite material samples containing 1, 5 and 10 % SiC hybrid filler at maximum stretch (1 %) is about 19, 21 and 22, respectively.

Metal nanoparticles loaded polyurethane nano-composites and their catalytic/antimicrobial applications: a critical review

Abstract Polyurethane (PU) belongs to a unique class of polymers. Different properties of PU such as mechanical strength and biocompatibility can be enhanced by co-polymerizing it with different bio and synthetic polymers. It finds huge applications as micro-reactors for the fabrication of metal nanoparticles (MNPs) owing to the synergistic properties of both polyurethane and fabricated metal nanoparticles. Metal nanoparticles fabricated polyurethane have gained much attention in the last few years. These types of nanocomposites hyphenate the mechanical properties of polyurethane with the high surface-to-volume ratio of metal nanoparticles. Here, this review article briefly evaluates different methods of synthesis of polyurethane-based metal nanocomposites and their characterization via different techniques to evaluate their properties. Applications of these polyurethane based nanocomposite materials have also been described critically in different fields depending upon their catalytic, antimicrobial and antifungal potential. Future directions of these nanocomposite materials have also been described in the field of designing of nano-filters and nano-devices in order to attain environmental remediation and sustainability.

Polymer-assisted synthesis of ternary magnetic graphene oxide nanocomposite for the adsorptive removal of Cr(VI) and Pb(II) ions

The presence of chromium [Cr(VI)] and lead [Pb(II)] ions in the water bodies have adverse effects on humans and aquatic life. Graphene oxide-based magnetic nanocomposites synthesized in the presence of chitosan (mGO/CS) or polyaniline (mGO/PA) as potential adsorbents for the removal of Cr(VI) and Pb(II) ions. The FTIR (Fourier transform infrared spectroscopy), EDX (Energy dispersive X-ray), XRD (X-ray diffraction) and SEM (Scanning electron microscopy) were employed to investigate the chemical composition, structural, elemental analysis, crystalline size and morphology of the nanocomposites. The FTIR results confirmed the synthesis of the nanocomposites by detecting peaks of specific functional groups. The average crystallite sizes of the mGO, mGO/CS, and mGO/PA nanocomposites were 17, 25, and 23 (nm), respectively, as determined by the Debye-Scherrer equation from the XRD data. Batch adsorption experiments were conducted for Pb(II) and Cr(VI) removal by varying the variables like pH, concentration of metal ions and contact time. The Box Behnken design (BBD) was used to optimize the adsorption parameters. Under the optimum conditions, mGO/CS and mGO/PA showed maximum removal percentages (%R) of 92.36 and 98.7 for Pb(II), and 85.25 and 93.08 for Cr(VI), respectively. The adsorption capacities were 110.84 and 118.44 mg/g for Pb(II), and 87.74 and 111.7 mg/g for Cr(VI) were obtained for mGO/CS and mGO/PA, respectively. The pseudo-second-order kinetic model and Langmuir isotherm fitted well to the experimental data and explain the adsorption mechanism of the nanocomposite materials for both metal ions.