Preparation Of Nanocomposites Research Articles

Tribological Behavior of Friction Stir Processed Nanocomposite Prepared Through Self-Assembled Monolayer Technique

Abstract An attempt was made to use friction stir processing, a manufacturing technique usually employed for the fabrication of nanocomposites. For the substrate, AA7075 was used and for dispersed phase, B4C nanoparticles of size (<30 nm) were selected. Nanocomposite samples were fabricated using three different tool rotation speeds of 1000, 1200, and 1400 rpm, by keeping other process parameters as constant, and their influence on the nanocomposite was judged by the study of tribological behavior and microhardness. This research work aims at the self-assembled monolayer formation of B4C nanoparticles homogeneous layer into a substrate material and hence minimizing the quantity of nanoparticles required in the preparation of nanocomposites via FSP. The results in terms of increased microhardness compared to the substrate material are reflected by the sample processed at the tool rotation of 1200 rpm. The average microhardness was found out to be 195 Hv compared to the substrate material. There is a maximum increment attained in wear resistance upto 46.7% in the sample processed at 1200 rpm. Worn out surface morphology were analyzed through scanning electron microscopy, and X-ray diffraction was also undertaken to analyze the presence of reinforcement particle in the fabricated nanocomposites.

Differential insulin response characteristics of graphene oxide-gold nanoparticle composites under varied synthesis conditions.

The structural alterations in the constituent materials of nanocomposites such as graphene nanocomposites typically induce changes in their properties including mechanical, electrical, and optical properties. Therefore, by altering the preparation conditions of nanocomposites and investigating their responsiveness to basic biomolecules (such as proteins), it is possible to explore the application potentials of the composites and guide development of new nanocomposite preparation. In this study, different composites of graphene oxide and gold nanoparticles (AuNPs/GO) were obtained by varying the volumes of reducing agents used in the one-pot hydrothermal method. Insulin was chosen as a basic protein to study the response characteristics of AuNPs/GO under different preparation conditions. Optical responses of these composites to pure insulin and various commercial insulin types were all explored for the first time. The results indicated that AuNPs/GO could optically respond to insulin, including pure insulin and various types of commercial insulin, and changes in the preparation conditions could really influence this response. Moreover, optimal preparation conditions could be determined by an optical method for the largest responses of the nanocomposites to insulin. Based on previous research and the results of this study, it is speculated that the responses of AuNPs/GO to insulin may attribute to glutamic acids, asparagines, and glutamines on insulin, which may interact with AuNPs/GO, particularly with the AuNPs in the composites. Besides, the AuNPs/GO could exhibit relatively stable responses to various commercial insulin types and detect the concentration of specific branded commercial insulin with smaller errors. In summary, this study demonstrated the application potential of AuNPs/GO in areas such as drug testing and production, while also furnishing an experimental foundation and direction for further applications of AuNPs/GO in biosensing and biomolecule detection.

Sulfur functionalized diamondoid phosphines enable building nanocomposites interfacing sp3-carbon and gold nanolayers.

Interfacing metal frameworks with carbon-based materials is attractive for the bottom-up construction of nanocomposite functional materials. The stepwise layering of difunctionalized diamantanes and gold metal from physical and chemical vapor deposition for the preparation of nanocomposites inverts the conventional preparation of metal-organic frameworks (MOFs) and self-assemblies, where the metal is introduced first, and this method delivers metal surfaces with modified properties originating from the sp3-carbon core. However, appropriate diamondoid candidates for such an approach are rare. By the mild chemical vapor deposition of the organometallic complex MeAuPMe3, gold coating is achieved on a diamantane SP(V) sulfide primary phosphine diamantanol 2. This later leads to sulfide and polysulfide surface rearrangement and provides a suitable substrate for metal-organic nanocomposite formation through a fully-dry vapor process, with the advantage, in contrast to the P(III) primary phosphine phosphinodiamantanol 1, of being resistant to uncontrolled oxidation at phosphorus during physical vapor deposition (PVD) and chemical vapor deposition (CVD) processing.

Preparation of polyhydroxyalkanoate nanocomposites for biomedical applications

AbstractPolyhydroxyalkanoates (PHAs) have been recognized as potential replacements for fossil fuel‐based, non‐biodegradable plastics. PHAs exhibit properties that are analogous to those of synthetic plastics. The production of PHAs offers a multitude of advantages, primarily due to their biodegradability and biocompatibility. The most naturally occurring form of PHAs are the polyhydroxybutyrates (P(3HB)s). The major limitations of P(3HB)s are their brittle nature and inferior mechanical properties. Hence, these biopolymers have been observed to have limited biotechnological applications. In contrast to P(3HB)s, copolymers of PHAs have almost all the desirable properties, making them suitable for high‐end applications such as those in the medical sector. Structural modifications in PHA molecules have expanded the scope of their applications, including in medical implants, wound healing and bone grafts. It is noteworthy that considerable progress has been made in the field of PHA nanocomposites, which are now being explored for their biotechnological applications in drug delivery, tissue engineering and biosensors. The prospects for PHA nanocomposites are also summarized. © 2025 Society of Chemical Industry.

Preparation and characterization of nano composites from metal oxides and activated carbon from banana peel (MO@BPAC, MO=NiO, CuO and ZnO) for 2 nitrophenol removal from aqueous solutions.

In this research, activated carbon from banana peel (BPAC) was prepared by calcination (600°C) method. Nano composites MO@BPAC (MO=NiO, CuO and ZnO) were prepared and then were characterized by XRD, FTIR, FESM, EDX, BETand TGA methods. Formation of MO@BPAC nanocomposites was confirmed by analysis methods. The XRD patterns showed formation of nanocomposites did not change crystalline phase of metal oxides. TGA analysis also showed the MO@BPAC had high thermal stability to 780°C. Removal of 2-nitrophenol by MO@BPAC nanocomposites was studied. The optimum contact time of 80min for NiO@BPAC, 100min and 120min for ZnO@BPAC and CuO@BPAC was observed. The order of percent removal of 2-nitrophenol by nanocomposites was as follow: NiO@BPAC>CuO@BPAC>ZnO@BPAC. The maximum removal of 2-nitrophenol 40mg L-1was attained at pH 9 and sorbent dose of 0.12g. The kinetic studies showed adsorption of 2-nitrophenol was described better by pseudo second order kinetic model than pseudo first order kinetic. The studies for equilibrium data showed Langmuir isotherm model gave better correlation with the experimental data (qe=303mgg-1 for NiO@BPAC). Thermodynamic parameters indicated adsorption of 2-nitrophenol by MO@BPAC nanocomosites were spontaneous and endothermic. The NiO@BPAC could be reused fourth cycles.

Preparation, microstructure, and mechanical properties of enamel-like nanocomposites for dental repair application

<p>Tooth enamel, as the hardest and the most resilient bioceramic material (~95.5 wt% apatite minerals) in human body, forms complex, highly ordered, hierarchical hetero-phase array structure over millions of years of evolution. This multiscale complex structure endows tooth enamel with excellent mechanical stability (especially the resistance to fracture, wear, and impact), high chop efficiency, and superb durability. However, in the complex oral environment, several factors such as oral bacteria, acidic foods, and mechanical collisions, can cause the dissolution of apatite crystals and even the damage of the enamel, resulting in a series of lesions such as dental caries that severely affects human health and life quality. Therefore, the urgent need for restoring to the normal function of natural teeth by repairing enamel has motivated researchers to develop advanced synthetic strategies for constructing artificial enamels. In this review, based on the understanding of the hierarchical heterogeneous structure-mechanical property-function relationship of natural human tooth enamel, we firstly introduced several synthetic strategies of biomimetic enamel nanocomposites such as cell-based tissue engineering, organic matrix-guided crystal growth, microgel-based microenvironment mineralization, amorphous precursor mineralization, and physicochemical methods, as well as presenting their microstructures and mechanical properties published in recent years. Finally, we discussed the biological safety of these artificial enamel nanocomposites and their dental repair applications.</p>

Microwave-assisted preparation of nanocomposite of copper bismuth sulphide containing metallic bismuth (Cu-Bi-S) towards negative electrode for supercapacitor application: An effort at optimizing the relative concentration of copper and bismuth

Microwave-assisted preparation of nanocomposite of copper bismuth sulphide containing metallic bismuth (Cu-Bi-S) towards negative electrode for supercapacitor application: An effort at optimizing the relative concentration of copper and bismuth

Biomolecular Interaction of Carnosine and Anti-TB Drug: Preparation of Functional Biopeptide-Based Nanocomposites and Characterization through In Vitro and In Silico Investigations

Biomolecular Interaction of Carnosine and Anti-TB Drug: Preparation of Functional Biopeptide-Based Nanocomposites and Characterization through In Vitro and In Silico Investigations

Preparation and Characterization of Copper Oxide-Chitosan Nanocomposite for Colon-Targeted Drug Delivery System

This work aimed at synthesizing the chitosan-based nanocomposite for concurrent diagnosis of colon tumors and targeted drug shipping with minimum toxicity. CuO-chitosan nanocomposite was developed using CuO nanoparticles (NPs), chitosan raw materials and 1% acetic acid. FE-SEM/EDX, TEM, XRD, DLSUV-Vis, FT-IR, as well as fluorescent emission spectrum methods were used to investigate the characteristics of nanocomposite gained throughout distinct levels. Bovine serum albumin (BSA) protein release rate was estimated. We investigated the antibacterial functioning of the nanocomposite against different bacteria types (like S. aureus, S. typhi, E. coli, L. monocytogene and P. aeruginosa), which can affect in causing tense colonic diseases. Qualitative and quantitative surveys were performed. The impact of the nanocomposite on cancerous and normal human colon cell lines, specifically HCT-116 and SW-948, was examined using the MTT assay. Eventually, loading BSA onto the CuO–chitosan nanocomposite enhances its potential as a drug carrier for treating colon cancer, causing minimal harm to surrounding normal cells. Additionally, the CuO-chitosan nanocomposite demonstrated significant antibacterial activity against Escherichia coli, a key pathogen associated with Crohn’s disease and ulcerative colitis.

Preparation and structural characterization of PbO and WO3-PVC hybrid nanocomposites for gamma-ray radiation shielding

Preparation and structural characterization of PbO and WO3-PVC hybrid nanocomposites for gamma-ray radiation shielding

Preparation of carboxymethyl cellulose-based silica hydrogel nanocomposite for methylene blue and malachite green dyes adsorption from aqueous solution

Preparation of carboxymethyl cellulose-based silica hydrogel nanocomposite for methylene blue and malachite green dyes adsorption from aqueous solution

Insights into Selective Sensitivity of In2O3-CuO Heterojunction Nanocrystals to CH4 over CO and H2: Experiments and First-Principles Calculations.

Metal oxide semiconductor gas sensors have demonstrated exceptional potential in gas detection due to their high sensitivity, rapid response time, and impressive selectivity for identifying various sorts of gases. However, selectively distinguishing CH4 from those of CO and H2 remains a significant challenge. This difficulty primarily stems from the weakly reducing nature of CH4, which results in a low adsorption response and makes it prone to interference from stronger reducing gases in the surroundings. Herein, we synthesized In2O3-xCuO nanocomposites using a hydrothermal method to explore their gas sensing properties toward CH4, CO, and H2. Characterization tests confirmed the successful preparation of In2O3-xCuO nanocomposites with different In:Cu molar ratios and the formation of a p-n heterojunction. The gas sensing test results indicated that the In2O3-2.1CuO nanocomposites calcined at 500 °C and measured at 350 °C displayed a p-type response for CH4 and an n-type response for CO and H2, allowing for accurate differentiation of CH4 from CO and H2. Moreover, the In2O3-2.1CuO sensor also showed excellent stability and reproducibility across all three gases. First-principles calculations revealed distinct changes in the electronic structure of the In2O3-CuO heterojunction upon adsorption of CH4, CO, and H2, a finding that aligns with empirical evidence. The gas selectivity mechanism was effectively explained by variations in the energy band gap, driven by electrical behavior during the adsorption process. This work suggests a promising approach for developing selective gas sensors capable of detecting weakly reducing gases.

Sonochemical preparation of nanocomposites of gold nanoparticles and graphene oxide for selective electrochemical sensing of nitric oxide

Abstract In this study, gold nanoparticles and graphene oxide nanocomposite-modified electrodes were prepared by the sonochemical method. We evaluated their electrocatalytic activity toward nitric oxide (NO) oxidation and the analytical performance in the determination of NO and demonstrated its improved selectivity in the detection of NO over NO2−.

Enhanced ORR Activity of MnO2 Nanoparticles through Direct Chemical Surface Attachment for Aluminum-Air Batteries

Manganese dioxide has garnered significant attention as a promising catalyst for the oxygen reduction reaction (ORR) in alkaline media due to its excellent catalytic activity, low cost, durability, and scalability. Despite its promising catalytic activity, MnO2 suffers from limitations such as low conductivity, particle dissolution, and diminished mass transport properties, particularly in high-throughput environments. Researchers typically couple MnO2 with high conductivity and high surface area materials such as conductive carbon black to overcome these challenges. However, this method still presents challenges, such as diminished catalyst-carbon interactions and the loss of catalytic active sites by the surrounding of larger carbon particles.In this study, we present a two-step synthesis method, initially proposed for the application of MnO2 as supercapacitor materials1, for the improvement of MnO2 catalytic activity towards the ORR. This synthesis method was achieved using diazonium chemistry, which involves the direct chemical attachment of KJB carbon black with MnO2 via a phenyl group linkage site. This process was done so that the mass ratio of MnO2 and KJB was 50:50. The synthesized materials were characterized using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Energy Dispersive X-ray Spectroscopy (EDX) to confirm varying morphologies, particle sizes, and material compositions. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) were utilized to analyze the phases and crystallinities of the materials. Each characterization step was done before and after the chemical attachment process to ensure the modifications were performed.The electrochemical activity of the materials was investigated using three-electrode cells to study the ORR activities and stabilities of the synthesized materials. Rotating disk electrode (RDE) and rotating ring-disk electrode (RRDE) data were employed to analyze kinetic current densities, the number of electrons transferred, and the hydrogen peroxide production rates. Furthermore, the catalyst materials were implemented into aluminum-air battery configurations where polarization curves, electrochemical impedance spectroscopy (EIS), and multistep chronoamperometry experiments were conducted to evaluate the performance of the modified MnO2 catalyst materials. Overall, implementing this process led to substantial increases in the catalytic activities morphologically dependent MnO2 particles towards the ORR and highlighted the significance of this research in advancing the understanding and application of MnO2 catalysts in energy conversion and storage technologies.[1] Ramirez-Castro, C., Crosnier, O., Athouël, L., Retoux, R., Bélanger, D., & Brousse, T. (2015). Electrochemical Performance of Carbon/MnO 2 Nanocomposites Prepared via Molecular Bridging as Supercapacitor Electrode Materials. Journal of The Electrochemical Society, 162(5), A5179–A5184.

Preparation of ZnS-Based Nanocomposites by Thermolysis of Zinc-Containing Monomers in the Presence of Thiourea: Their Characterizations and LPG Sensing Applications

Preparation of ZnS-Based Nanocomposites by Thermolysis of Zinc-Containing Monomers in the Presence of Thiourea: Their Characterizations and LPG Sensing Applications

Multifunctional Ag-Poly(N-isopropylacrylamide/itaconic Acid) Hydrogel Nanocomposites Prepared by Gamma Irradiation for Potential Application as Topical Treatment Dressings.

Today, hydrogel dressings that can protect injury sites and effectively promote healing have become highly desirable in wound management. Therefore, multifunctional silver-poli(N-isopropylacrylamide/itaconic acid) (Ag-P(NiPAAm/IA)) hydrogel nanocomposites were developed for potential application as topical treatment dressings. The radiolytic method, used for the crosslinking of the polymer matrix as well as for the in situ incorporation of silver nanoparticles (AgNPs) into the polymer matrix, enables the preparation of hydrogel nanocomposites without introducing harmful and toxic agents. Moreover, materials produced using γ-irradiation are simultaneously sterilized, thus fulfilling one of the basic requirements regarding their potential biomedical applications. The NiPAAm/IA ratio and the presence of AgNPs influenced the microstructural parameters of the investigated systems. Increasing the IA content leads to the formation of a more porous polymer matrix with larger pores, while the incorporated AgNPs act as additional junction points, decreasing the porosity and pore size of the resulting nanocomposite hydrogels. Swelling studies showed that most investigated systems uptake the fluids from their surroundings by non-Fick diffusion. Further, the Ag+ ion release, antibacterial activity, and cytotoxicity of Ag-P(NiPAAm/IA) hydrogel nanocomposites were examined to evaluate their biomedical potential. All hydrogel nanocomposites showed an initial burst release of Ag+ ions (useful in preventing bacteria adherence and biofilm formation), followed by a slower release of the same (ensuring sterility for longer use). An antibacterial activity test against Escherichia coli and Staphylococcus aureus showed that Ag-P(NiPAAm/IA) hydrogel nanocomposites, with silver concentrations around 10 ± 1 ppm, successfully prevent bacterial growth. Finally, it was shown that the investigated hydrogel nanocomposites do not exhibit a cytotoxic effect on human keratinocyte HaCaT cells. Therefore, these multifunctional hydrogel nanocomposites may promote wound repair and show promising potential for application as functional wound dressing.

Point‐of‐care testing of DNA damage markers‐8‐hydroxy‐2′‐deoxyguanosine based on cobalt‐iron‐platinum‐ruthenium/N doped ordered mesoporous carbon

AbstractIn this work, we achieved point of care detection of DNA damage marker 8‐hydroxy‐2’‐deoxyguanosine (8‐OH‐dG) on tetrapartite metal nanoparticles loaded ordered mesoporous carbon composite nanomaterials (Co‐Fex‐Pt−Pd@NOMC). Nitrogen doping and co‐metal loading were achieved using dopamine as nitrogen, carbon sources and metal linker. In addition, the presence of catechol groups in dopamine with strong affinity for metal ions, make the simultaneous confinement of metals inside and outside the pores of ordered mesoporous carbon. Then, Fe, Pt and Pd metal nanoparticles were introduced to interact with Co nanoparticles to form four‐in‐one alloy nanoparticles by oil bath and carbonisation. The finally formed Co−Fe6‐Pt−Pd@NOMC nanocomposites exhibited excellent catalytic performance for the determination of 8‐OH‐dG. A lower limit of detection (LOD) of 0.044 μM, a wide linear range (0.175 μM–118.375 μM) and strong stability, reproducibility and selectivity were obtained. In addition, Co−Fe6‐Pt−Pd@NOMC realised the detection of 8‐OH‐dG in real human urine sample. At the same time, 8‐OH‐dG after DNA damage and guanine damage were also studied in this work. The electrochemical response of 8‐OH‐dG was combined with DNA damage to verify the mechanism of DNA damage. New solutions and idea were provided for the preparation of inorganic nanocomposites for the detection of 8‐OH‐dG in this work.

Preparation and characterization of nanocomposites based on natural rubber/chlorobutyl rubber/graphene nanoparticle: Effect of feeding sequences, mixer type and nanoparticle concentration

AbstractBlends of natural rubber (NR)/chlorobutyl rubber (CIIR) (50/50), along with their nanocomposites containing varying amounts of graphene nanoparticles (GNPs) with and without silane, were prepared using different feeding sequences and mixers. The results indicated that when GNP was first mixed with NR before adding CIIR, the highest GNP content was found in NR; the oxygen permeability and diffusion coefficient decreased significantly by 37% and 55%, respectively. Conversely, when graphene was initially added to CIIR, it was distributed in both rubbers and at the interface, enhancing phase interaction and achieving a finer morphology. This sample exhibited the greatest improvement in mechanical properties due to specific localization of GNP and increased crosslink density. Using an internal mixer instead of a two‐roll mill improved graphene dispersion, reduced curing time, and enhanced mechanical properties. Although the presence of silane reduced graphene dispersion, it improved mechanical and barrier properties due to increased crosslink density. Oxygen permeability was reduced by up to 36% at 3 phr of GNP content with silane. This research proves that the mixing order and the type of mixing equipment are crucial in determining the final performance of rubber composites, as they significantly influence the dispersion and localization of fillers.Highlights NR/CIIR/GNP nanocomposites were prepared by different methods and evaluated. Adding NR/GNP to CIIR led to more presence of GNP in NR and lower permeability. By adding CIIR/GNP to NR, GNP were placed more at interface, modulus improved. Mixing in an internal mixer improved GNP dispersion compared to a two‐roll mill. Silane improved mechanical and barrier properties of NR/CIIR/GNP nanocomposite.

Silica gels doped with gold nanoparticles and gold thiolate complexes: The effect of heating and preparation conditions

A novel sol-gel strategy for the preparation of silica nanocomposites, containing gold nanoparticles (AuNPs), Au(I)-thiolate complexes (Au-SC12) or both disperse phases is demonstrated. The color of the species depends on the size and surrounding of the AuNPs. The nanocomposites obtained are characterized with UV/Vis reflectance spectroscopy, X-Ray diffraction, TEM / EDAX and thermal conductivity measurements. An analysis of the UV/VIS spectra, based on Mie's theory, suggests the presence of 5 - 30 nm AuNPs with different chemical surroundings. Heating of the nanocomposites at 700 °C leads to red or violet colored SiO2:AuNPs powders. The thermal conductivity of the nanocomposites is about 0.05–0.07 W/m.K, depending on sintering and chemical composition. A discussion about the microstructure of the composites is also presented.

Electrochemical studies of ytterbium doped Cu/Co nanoparticles synthesized by green fabrication using Callistemon viminalis leaves extract

AbstractBACKGROUNDUtilization of phytochemicals for the preparation of metal oxides nanocomposites has been proven to be a best alternate of chemical synthesis methods. Here, we have extracted, isolated and characterized the phytochemicals of Callistemon viminalis plant extract and utilized them as biofuel in the synthesis of Cu/Co and doped Cu/Co nanoparticles. Callistemon viminalis has been shown to have reducing and stabilizing properties. The plant extracts contain a variety of bioactive substances, including tannins, vitamins, amino acids, saponins, inositol, alkaloids, flavonoids, and terpenes. The use of plant extracts in the synthesis of NPs is a quick, dependable, nontoxic, benign, environmentally friendly, and cost‐effective method. Thus, in the present work, the Callistemon viminalis leaves extract a synthesis of Cu/Co nanoparticles and ytterbium doped Cu/Co nanoparticles, and these nanoparticles were characterized by optical properties (UV), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), X‐rays diffraction (XRD), and electrochemical application.RESULTSSynthesis of Cu/Co nanoparticles and ytterbium doped Cu/Co nanoparticles at room temperature have been successfully done using Callistemon viminalis aqueous leaf extract. Products were confirmed by conducting UV‐ visible spectrophotometry, FTIR, SEM, and XRD confirming the formation of cubic shaped Cu/Co nanoparticles of average diameter of 14 nm. The aqueous leaf extract acted as a capping agent and the existence of organic functional groups were confirmed by FTIR. Upon varying the Yb content in Cu/Co, the particle's size obtained from SEM showed a decrease in size. The band gap energies were also reduced with Yb doping. The stability of the produced NPs was investigated using linear sweep voltammetry LSV on this special and innovative metal oxide electrode. The LSV analysis has shown an elevation in the scan rate detection with an increase in voltage. 55.6 μA current was detected at 10 V for Cu/Co NPs. Ytterbium doped nanoparticles have shown 471.3 μ current voltage value at scan rate of 10 V. Observed value of current of synthesized Cu/Co NPs was 5.7 μA and the observed current of doped Yb(Cu/Co) was 12.5 μA. The increase in current values of dopant Cu/Co nanoparticles is due to the higher pore volume and surface area of copper, which promotes the transfer of electrons, so the current density is greater of the doped material than the composite NPs. The electrical resistivity of Cu/Co nanoparticles has shown a decline with elevation in current indicating its semiconducting nature.CONCLUSIONIn summary, biologically synthesized Cu/Co and ytterbium doped Cu/Co nanoparticles at room temperature have been successfully synthesized based on the greener approach using Callistemon viminalis aqueous leaf extract. The utilization of the Callistemon viminalis plant‐mediated approach, which makes the procedure more affordable and environmentally benign than chemical synthesis, is one of the study's major contributions. © 2024 Society of Chemical Industry (SCI).