Nanocomposite Structure Research Articles

The effect of nickel oxide nanoparticles on the structure and properties of nanocomposites based on high-pressure polyethylene containing multiwalled carbon nanotubes

The effect of nickel oxide nanoparticles on the structure and properties of nanocomposites based on high-pressure polyethylene containing multiwalled carbon nanotubes

Synthesis of Nanocomposite Based Polysaccharide and Performance Evaluation for the Removal of Various Drug from Pharmaceuticals Wastewater

AbstractThe present study performed synthesis and characterization nanocomposite based polysaccharide Chitosan/Agar and Chitosan/Agar/SiO2 nanoparticles as adsorbents for remove amoxicillin and naproxen as the pharmaceuticals from an aqueous solution. The structure and morphology of nanocomposite were investigated using X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy (EDX), Fourier‐transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Field Emission Scanning Electron Microscopes (FE‐SEM) and Dynamic light scattering (DLS). The removal performance of the Chitosan/Agar and Chitosan/Agar/SiO2 nanoparticles nanocomposite as adsorbent for removing amoxicillin and naproxen as sample of pharmaceutical industry effluents in aqueous solutions was investigated under different influence factors, including contact time, initial concentration, pH conditions and temperature. The maximum adsorption removal for amoxicillin with Agar/Chitosan and Agar/Chitosan/SiO2 nanocomposite at initial concentrations of 20 mg/l was 97.85 % and 87.9 %, respectively. With increasing temperature from 10 to 30°C, the removal efficiency for naproxen for both adsorbents is 99 %. The prepared nanocomposites showed good performance in adsorbing naproxen and amoxicillin. The maximum adsorption efficiency of nanocomposite was 99 % and 91 % for naproxen and amoxicillin, respectively. The optimum condition for pharmaceuticals removal by the nanocomposite was initial concentration: 20 mg/l, adsorbent dose: 0.05 g, contact time: 10 min, and pH=6.

Fabrication of novel SiOxNy/SWCNT laminate-type composite protective coating using low-temperature approach

Multifunctional thin films are becoming extremely popular in many technological fields. An increase in their functionality can be achieved by the creation of nanocomposite structures. This study represents novel thin composite coatings with a horizontally oriented single-walled carbon nanotube (SWCNT) filler inside a silicon oxynitride (SiOxNy) matrix obtained by (i) low-temperature thermal curing or by (ii) UV radiation-induced curing. The SiOxNy/SWCNT composite structures were prepared by simple dry transfer of a SWCNT film into a perhydropolysilazane (PHPS) polymer matrix film deposited by the spin-coating technique followed by curing. The structural, morphological, and optical properties of the SiOxNy/SWCNT composite films were studied using HR-SEM/EDX, ATR-FTIR, and UV–Vis spectroscopy. It was found that SWCNT films were uniformly transferred into the PHPS matrix, maintaining their horizontally oriented close-packed structure, and avoiding the problem of agglomeration, thereby forming a laminate-type composite. SWCNTs had no effect on the curing process of the PHPS matrix. The SWCNT concentration remained relatively low, resulting in highly transparent composite films. An antireflection effect in the composite film relative to the transmission of the SWCNT film was observed. The results indicate that SiOxNy/SWCNT composites are attractive for applications as protective, antireflective optical coatings.

Biogenesis of bacterial cellulose/xanthan/CeO2NPs composite films for active food packaging

The increasing significance of biopolymer-based food packaging can be attributed to its biodegradability and independence from petroleum-derived materials. Concurrently, metal oxide nanoparticles (NPs) have gained prominence as effective antimicrobial agents against both wild-type and antibiotic-resistant microbes. In this study, cerium oxide or ceria, CeO2, nanoparticles with an average diameter of 50 nm were synthesized via a green method utilizing Vibrio sp. VLC cell lysate supernatant. The synthesized CeO2 NPs displayed remarkable antimicrobial properties, inhibiting the growth of Escherichia coli and Staphylococcus aureus by 93.7 % and 98 %, respectively. To enhance the potential of bacterial cellulose (BC) for advanced applications, we developed a BC/xanthan/CeO2 nanocomposite using both ex situ and in situ techniques. The integration of CeO2 NPs within the nanocomposite structure not only improved the inherent properties of BC, but also rendered it suitable for use in active food packaging systems. The nanocomposite exhibited no significant cytotoxicity on the human dermal fibroblast (HDF) cells, confirming its safety. Nanocomposites containing biogenically synthesized CeO2 NPs demonstrated exceptional efficacy for reducing microbial contamination. Bread samples coated with nanocomposite films displayed no signs of microbial growth. These results support the application of BC/xanthan/CeO2 nanocomposites as suitable and effective coating materials for antimicrobial food packaging applications.

Ag/Fe3O4 bifunctional nanocomposite for SERS detection of non-steroidal anti-inflammation drug diclofenac

In this work, a bifunctional nanocomposite based on silver and iron oxide nanoparticles (AgNPs/Fe3O4) was prepared and then used as SERS substrate (surface-enhanced Raman spectroscopy) for sensing diclofenac which is one of the most widely used non-steroid anti-inflammation drugs. AgNPs/Fe3O4 nanocomposite was synthesized by combining co-precipitation of iron oxide and in-situ reduction of silver nanoparticles. Morphology and structural studies revealed a conjugated structure in which silver nanoparticles (80 nm in diameter) were surrounded by iron oxide nanoparticles (18 nm in diameter). There is a slight blue-shift in position of plasmon peak from 405 nm for silver nanoparticles to 375 nm for AgNPs/Fe3O4 nanocomposite. Even the saturation magnetization (Ms) of the Ag/Fe3O4 nanocomposite only reached 28 emu.g-1 but still good enough for immobilizing nanocomposite structures onto the substrate. The use of AgNPs/Fe3O4 nanocomposite as SERS substrate for sensing application was demonstrated with using diclofenac as a model. The detection limit and enhancement factor of the SERS-based diclofenac sensor were found to be 10-12 M and 2.6×1010, respectively. Such kind of bifunctional nanocomposite will probably help us to avoid time-consuming process to immobilize metal nanoparticles onto the surface, and also allow us to regenerate the substrate for multiple uses.

Fabrication of composite GO/NiFe2O4-MnFe2O4-CoFe2O4 anode material: Toward high performance hybrid supercapacitors.

Here, NiFe2O4, MnFe2O4, and CoFe2O4 nanoferrites are prepared by coprecipitation synthesis technique from nickel, manganese, and cobalt chloride precursors. Synthesized nanoferrites are annealed by calcination process at 800°C for 2 h. To produce a novel anode electrode material for asymmetric supercapacitors (ASCs), the composite material of GO/NiFe2O4-MnFe2O4-CoFe2O4 is fabricated. Physicochemical aspects of the synthesized nanoferrites are evaluated. X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and x-ray photoelectron spectroscopy tests are conducted, respectively. The electrochemical activities are studied by cyclic voltammetry, glavanostatic charge-discharge, and electrochemical impedance spectroscopy (EIS) in 2 M KOH as the electrolyte. In three electrode system, the novel GO/NiFe2O4-MnFe2O4-CoFe2O4 electrode displays a high specific capacity of 325 C g-1 and preserves about 99.9% of its initial specific capacity. The GO/NiFe2O4-MnFe2O4-CoFe2O4//GO ASCs device is assembled using GO/NiFe2O4-MnFe2O4-CoFe2O4, GO, and 2 M KOH solution as the positive electrode, negative electrode, and electrolyte, respectively. Significantly, the GO/NiFe2O4-MnFe2O4-CoFe2O4//GO ASCs represent an outstanding energy density of 50.5 W h kg-1 at power density of 2560 W kg-1. Through the long-term charge discharge cycling tests, this ASC device illustrates about 93.7% capacity retention after 3000 cycles. Then, the present study provides the NiFe2O4-MnFe2O4-CoFe2O4 composite nanoferrites as a novel favorable candidate for anode material. RESEARCH HIGHLIGHTS: Simple and green synthesis of magnetic NiCo2O4/NiO/rGO composite nanostructure using natural precursor. Fabricating and designing an efficient semiconductor for degradation ability. NiCo2O4/NiO/rGO nanocomposite with advanced photo elimination catalytic routine. The photocatalytic performance of NiCo2O4/NiO/rGO was surveyed for the degradation of various antibiotics below visible radiation. Efficiency was 92.9% to eliminate tetracycline. We developed a synergetic approach to prepare a novel active material composed of GO/ NiFe2O4-MnFe2O4-CoFe2O4 by a hybrid electrode material. Green synthesis method was accomplished to attain NiCo2O4/NiO/rGO nanocomposite with advanced photo elimination catalytic routine. The oxide nanobundles were prepared with a rapid and eco-friendly method. In order to investigation of the effect of natural precursor, morphology and shape of nanoproducts was compared. NiCo2O4/NiO/rGO nanobundles possess a suitable bandgap in the visible area.

Free Vibration of Thermally Loaded FG-GPLRC Nanoplates Integrated with Magneto-Electro-Elastic Layers in Contact with Fluid

This work investigates the free vibrations of innovative thermally loaded nanoplates constructed by integrating magneto-electro-elastic (MEE) layers with functionally-graded graphene platelet-reinforced composite cores (FG-GPLRC) and accounting for viscous fluid interactions. An advanced multiphysics model is developed using the Navier–Stokes equations to capture fluid structure coupling effects, Halpin–Tsai, and the rule of mixtures micromechanics to predict the non-uniform effective properties, third-order shear deformation plates theory (TSDPT) to incorporate thickness stretching, and the nonlocal strain gradient theory (NSGT) to characterize size dependencies. The Galerkin technique is used to solve the governing equations, which are derived from the Hamilton’s principle. Parametric analyses quantify the influences of fluid depth, temperature fluctuations, temperature profiles, nonlocal and strain gradient parameters, electric and magnetic potentials, graphene distribution patterns, graphene weight fractions, and boundary conditions on the vibration response. The outcomes of this study provide design guidelines and predictive tools enabling active vibration control systems for next-generation thermally-loaded nanocomposite structures with widespread applications from aerospace vehicles to nanoelectronics.

Structure and mechanical properties of multi-principal AlCrNbSiTiON oxynitride coatings

The multi-principal AlCrNbSiTiON oxynitride coatings were deposited by pulsed arc ion plating under different oxygen flow. The structure and mechanical properties of the coatings were systematically investigated. The surface of all coatings is smooth and flat. The cross section is compact and smooth. The coatings transform from FCC solid solution crystal structure with (200) preferred orientation to amorphous/nanocrystalline nanocomposite structure with increasing oxygen flow. Upon increasing oxygen flow from 0 to 150 SCCM, their hardness decreases from 43.4 to 15.6 GPa. The hardness of the coatings increases to 26.4 GPa with increasing oxygen flow again. The Cr2O3 oxides are formed on the surface of the coatings during the friction process.

Ferulic acid detection in honey using carbon paste electrode modified by C-C3N4/Li2CoMn3O8 nanocomposite

Honey is regarded as a valuable food commodity which has many and varied components, including phenolic compounds. Ferulic acid (FA) is one of these compounds, which possesses activities such as antioxidant, anti-inflammatory, anti-diabetic, haemolytic, antiviral, anti-cancer, etc. In view of these unique characteristics, a quick, sensitive, simple and inexpensive method for FA identification is required. This research developed a novel electrochemical sensor for measuring FA in honey samples. The sensor utilizes a C-C3N4/Li2CoMn3O8 nanocomposite modified carbon paste electrode (C-C3N4/LCMO/CPE) to enhance the sensitivity and detection. The synthesized nanocomposite exhibits remarkable properties, featuring an abundance of electrochemically active sites and enhanced electron transfer rates, making it ideal for developing advanced electrochemical sensors. The XRD, SEM and EDX analysis were used to examine and look like the synthesised nanocomposite structure. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods were used to evaluate the electrochemical behavior of C-C3N4/LCMO/CPE sensor for FA detection and optimized by adjusting pH, and potential scan rate. FA was measured in a phosphate buffered saline (PBS; 0.1 M, pH 4.0) by DPV with the detection limit of 3.6 nM and quantitative limit of 0.009 µM in the linear response ranges of 0.009–3.000 and 5.00–100 µM. Chronoamperometry was utilized to calculate the diffusion coefficient of FA (D = 3.45 (±0.11) × 10−6 cm2.s−1) on the surface of the C-C3N4/LCMO/CPE, as well as the electron transfer coefficient (α = 0.68). The sensor’s high sensitivity for accurately assessing FA in real samples was demonstrated by recovery values ranging from 96.96 to 102.36 %.

Leonardite humic acid activated carbon/MnO\(_{2}\) composite nanostructures for supercapacitors

Abstract This work reports the preparation and electrochemical studies of activated carbon derived from leonardite humic acid composited with MnO2 for supercapacitors. Activated carbon contains high conductivity, high specific surface area, and accommodates large volume expansion/contraction during charging/discharging process. Meanwhile, MnO2 has very high theoretical specific capacity (1370 F∙g‒1). Their composite could significantly improve both the storage performance and cycle stability of supercapacitors. Moreover, humic acid from leonardite was selected to add value to this waste and reduce environmental pollution. By varying the carbonization temperature (500℃ to 800℃), the prepared samples carbonized at 800℃ exhibited fascinating properties. The oxidation state of Mn ions was in the mixed state of Mn+2 (41.2%) and Mn+2, +3 (52.8%). A gravimetric capacitance of 329 F∙g‒1 and 294 F∙g‒1 were observed at 2 mVs-1 and 0.5 Ag-1, respectively. The remaining gravimetric capacitance of 193 F∙g‒1 was evaluated at 1000 cycles, indicating its high cycle performance. Moreover, the gravimetric energy of 37.51 Wh∙kg‒1 and gravimetric power of 272.96 W∙kg‒1 were observed. When combined, the interesting electrochemical properties of leonardite humic acid-activated carbon/MnO2 composite nanostructures make them important options for supercapacitor application.

Improving the sensing performance of SnWO4 nanostructure at room temperature based on CsPbBr3 composite

The accurate detection of hazardous gases and monitoring of ambient temperature are crucial for preserving the ecological environment, safeguarding human health, and fostering industrial advancement. In this research, a straightforward hydrothermal technique was employed to synthesize the heterogeneous nanocomposite structure of CsPbBr3/SnWO4, which facilitates the detection of ethanolamine gas at room temperature. The synthesized CsPbBr3/SnWO4 heterostructures underwent further analysis using XRD, SEM, HRTEM, XPS, BET and Mott-Schottky techniques. The findings revealed that the CsPbBr3/SnWO4 heterostructure exhibits a coarse cubic morphology, consisting of nano-cubic CsPbBr3 and nano-sheet SnWO4. Additionally, the integration of CsPbBr3 markedly enhances the specific surface area of the pristine SnWO4 nanosheets. Due to its coarse surface, expansive contact area, and n-n heterojunction, CsPbBr3–SnWO4 demonstrates remarkable selectivity, superior long-term stability, and a sensitivity of 45.6 to ethanolamine at ambient temperature. In conclusion, the CsPbBr3/SnWO4 heterostructure, constructed from a cube with a rough surface, is anticipated to serve as an effective room temperature sensor with heightened selectivity for ethanolamine.

In situ semi-etching of bimetallic LDH nanosheet arrays into FeNi-LDH/MOF to boost oxygen evolution reaction

The inherent sluggish kinetics of water oxidation is the core issue for electrochemical hydrogen production from water splitting. Metal organic frameworks (MOFs) with tunable porous structures, abundant coordination metal centers and large specific surface area are expected as efficient electrocatalysts. In this paper, FeNi-LDH/MOF composite nanostructures were successfully constructed on carbon cloth (CC) through partially converting iron-nickel layered double hydroxide (FeNi-LDH) into FeNi-MOF (NiFe(CN)5NO) by an in-situ semi-etching method. The MOF nanocrystals in this material are in-situ decorated on the surface of FeNi-LDH nanosheets, providing abundant open active sites and mass transfer channels for electrocatalysis. Thanks to the synergistic effect of the LDH and MOF, as well as the exceptional hierarchical architecture, the FeNi-LDH/MOF/CC as a self-supported electrode exhibits distinguished electrocatalytic OER performance, with a low overpotential of 263 mV@100 mA cm−2 and a small Tafel slope of 50.2 mV dec-1 in 1.0 M KOH. In addition, the catalyst exhibits good durability with almost constant current density during 24 h OER test. This work provides an effective way to design high-performance MOFs-based composite electrocatalytic materials.

On-surface conversion reaction realizes advanced red phosphorus/carbon anode for high-performance lithium-ion batteries

Red phosphorus (RP), the one of the most prospective anodes in lithium-ion batteries (LIBs), has been severely limited due to the intrinsic defects of massive volume expansion and low electronic conductivity. The vaporization-condensation-conversion (VCC), which confines RP nanoparticles into carbon host, is the most widely used method to address the above drawbacks and prepare RP/C nanostructured composites. However, the volume effect-dominated RP caused by the inevitably deposition of RP vapor on the surface of carbon material suffers from the massive volume change and unstable solid electrolyte interface (SEI) film. Herein, we propose a simple interfacial modification method to eliminate the superficial RP and yield stable surface composed of ion-conducting Li3PS4 solid electrolyte, endowing RP/AC composites excellent cycling performance and ultrafast reaction kinetics. Therefore, the RP/AC@S composites exhibit 926 mAh/g after 320 cycles at 0.2 A/g (running over 181 days), with 81.6 % capacity retention and a corresponding capacity decay rate of as low as 0.059 %. When coupled with LiFePO4 cathode, the full cells present superior cycling performance (62.1 mAh/g after 500 cycles at 1 A/g) and excellent rate capability (81.1 mAh/g at 1.0 A/g).

Hierarchical looping results in extreme extensibility of silk fibre composites produced by Southern house spiders (Kukulcania hibernalis).

Spider silk is a tough and versatile biological material combining high tensile strength and extensibility through nanocomposite structure and its nonlinear elastic behaviour. Notably, spiders rarely use single silk fibres in isolation, but instead process them into more complex composites, such as silk fibre bundles, sheets and anchorages, involving a combination of spinneret, leg and body movements. While the material properties of single silk fibres have been extensively studied, the mechanical properties of silk composites and meta-structures are poorly understood and exhibit a hereto largely untapped potential for the bio-inspired design of novel fabrics with outstanding mechanical properties. In this study, we report on the tensile mechanics of the adhesive capture threads of the Southern house spider (Kukulcania hibernalis), which exhibit extreme extensibility, surpassing that of the viscid capture threads of orb weavers by up to tenfold. By combining high-resolution mechanical testing, microscopy and in silico experiments based on a hierarchical modified version of the Fibre Bundle Model, we demonstrate that extreme extensibility is based on a hierarchical loops-on-loops structure combining linear and coiled elements. The stepwise unravelling of the loops leads to the repeated fracture of the connected linear fibres, delaying terminal failure and enhancing energy absorption. This principle could be used to achieve tailored fabrics and materials that are able to sustain high deformation without failure.

Synthesis of magnetic layered double hydroxide (Fe3O4@CuCr-LDH) decorated with ZIF-8 for efficient sonocatalytic degradation of tetracycline

A series of Fe3O4@CuCr-LDH hybrids decorated with different amount of ZIF-8 (FLZ, 10–40 wt%) was prepared using simple methods and characterized with different techniques. The activity of the synthesized nanocomposites was investigated in the sonocatalytic degradation of tetracycline (TC) antibiotic from wastewater. When the content of ZIF-8 in the nanocomposite structure was 20 wt%, the FLZ-20 sonocatalyst exhibited the high performance in the sonocatalytic removal of TC. At optimum conditions (0.7 g/L catalyst dosage, pH of 7, 50 mg/L initial concentration of antibiotic, and 15 min sonication time) of the sonocatalytic removal of TC approached to 91.4% under ultrasonic irradiation (USI) using FLZ-20. This efficiency was much higher than those of obtained results by Fe3O4@CuCr-LDH and pristine ZIF-8. The formed ●OH and ●O2− exhibited the major roles in the sonocatalytic TC degradation process. The excellent performance of FLZ-20 can be attributed to the heterojunctions created between composite components, which could improve the electron transfer ability and effectively separate e−/h+ pairs. In addition, FLZ-20 showed the superior reusability and stability during three successive recycling. Moreover, the facile magnetically separation of the sonocatalyst from the aqueous solution was another outstanding feature, which prevents the formation of secondary pollutants. It can be concluded that the fabrication of heterojunctions is an efficient procedure to promote the sonocatalytic acting of the catalyst.

Hunting of “two birds with one arrow” strategical design of Nb doped WO3 decorated on the BN nanosheet and their enhanced photocatalytic degradation of Rose Bengal dye and Chloramphenicol drug

In the present work, “Killing two birds (RB and CAP) with one arrow (Nb/WO3/BN)” plan of action was performed for the photocatalytic degradation of organic dye of Rose Bengal (RB) and organic drug of Chloramphenicol (CAP) was degraded under visible light irradiation with the active catalyst of Nb/WO3/10 % BN composite for first time. The as-prepared Nb/WO3 was functionalized with thin-sheet structure of BN nanocomposite was synthesized via acid precipitation method followed by ultra-sonication method. The effective formation of Nb/WO3/BN were characterized by using XRD, UV-DRS, XPS, SEM-EDS, TEM, Photoluminescence (PL) and electrochemical impedance spectroscopy (EIS). The XRD, UV-DRS results clearly revealed that formation of ternary phases in the composites. Formation of ternary composite also confirmed by the XPS analysis. The morphology of WO3, Nb/WO3 and BN were examined by the SEM analysis. Furthermore, the inner morphology of cubic structure of WO3 nanoparticles and Nb/WO3 were decorated on the surface of the BN nanosheet were approved by TEM analysis. Interestingly, photocatalytic degradation of RB revealed by 94.31 % within 60 min as well as CAP degraded 95.13 % within 60 min by Nb/WO3/10 % BN ternary composite under visible light irradiation. Meanwhile, the different prepared photocatalyst, Nb/WO3/10 % BN was found to be the most efficient photocatalyst for degradation of RB and CAP. This results ascribed to the 30 mg of the photocatalyst and 10 mg/L concentration were optimum loading for the degradation of RB and CAP. Scavenger studies were also confirmed in order to understand the mechanism of photodegradation process. It was noted that electrons and holes pair are generated by irradiation of light, followed by (.OH) radical plays a crucial role for the photodegradation mechanism. The active photocatalyst Nb/WO3/10 % BN shows a good stability at room temperature and it can be recycled and reused up to five successful cycles without the major loss in their performances. Therefore, these work revealed that, the best sequence of Nb/WO3/10 % BN nanocomposite is new plan of action for photodegradation of RB and CAP.

Synthesis, Structure, and Catalytic Properties of Nanocomposites Based on Palladium, Copper(I) Oxide, and Magnetite Nanoparticles Embedded in a Nanocellulose Matrix

Synthesis, Structure, and Catalytic Properties of Nanocomposites Based on Palladium, Copper(I) Oxide, and Magnetite Nanoparticles Embedded in a Nanocellulose Matrix

NiCoMn-LDH with core-shell heterostructures based on CoS nanotube arrays containing multiple ion diffusion channels for boosted supercapacitor applications

Nanostructure engineering and composition rationalization are crucial for materials to become candidates for high-performance supercapacitor. Herein, a novel core-shell heterostructured electrode, combining CoS hollow nanorods with NiCoMn-layered double hydroxides (LDH) ternary metal nanosheets, were prepared on carbon cloth by reasonably controlled vulcanization and electrodeposition. By optimizing electrodeposition conditions, the material's structure and properties can be fine-tuned. The enhanced capacitance of the optimized carbon cloth (CC)@CoS/NiCoMn-LDH-300 electrode (4256.0 F g−1) lies in the open space provided by CoS and the establishment of a new charge transfer channel across the interfaces of CC@CoS/NiCoMn-LDH-300 nanosheets. This is further demonstrated by Density functional theory (DFT) simulations based on OH− adsorption energy, which produces faster redox charge kinetics and significantly enhances the electrode's energy storage capacity. The hybrid supercapacitor, integrating the optimized CC@CoS/NiCoMn-LDH-300 electrode with active carbon, demonstrates the highest energy density of 86 Wh kg−1 (under the power density of 850 W kg−1) and the long cycle stability of 89.7%. This study aims to go beyond simple binary LDH by constructing a ternary LDH with a hierarchical core-shell heterostructure to provide an effective and feasible new concept for high-performance supercapacitor electrode materials via rational structure design.

Eco-synthesis route: Developing bis-hydrazono[1,2,4]-thiadiazoles via a green synthetic approach with calcium oxide-chitosan nanocomposite

Modern environmental organic chemistry is focused on developing cost-efficient, versatile, environmentally acceptable catalytic chemicals that are also highly effective. Herein, hybrid calcium-chitosan nanocomposite films was prepared by doping calcium oxide molecules into a chitosan matrix at weight percentage (15, 20, and 25 % wt. chitosan‑calcium) using an easy and affordable simple co-precipitation process. The CS–CaO nanocomposite's structure was elucidated using analytical techniques such as Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Based on the X ray diffraction (XRD) measurements, the crystallinity was reduced by the incorporation of the CaO molecules. Also, from the calculation of the Debye-Scherrer equation on this X-ray diffraction (XRD) pattern, the crystallite size was found to be 17.2 nm for the nanocomposite film with 20 % wt. The energy dispersive spectroscopy graph demonstrated the presence of the distinctive Ca element signals within the chitosan, with the amount in a sample of 20 % wt. being discovered to be 21.32 % wt. For the synthesis of bis-hydrazono[1,2,4]thiadiazoles, the obtained CS–CaO nanocomposite could be employed as a potent heterogeneous recyclable catalyst. Better reaction yields, quicker reactions, softer reaction conditions, and green reusable efficient biocatalysts for several uses are just a few advantages of this approach.

Hot injection synthesis of CuS decorated CdS and ZnS nanomaterials from metal thiosemicarbazone complexes as single source precursors: Application in the photocatalytic degradation of methylene blue

CdS and ZnS are considered excellent semiconductors for photocatalysis, but photocorrosion and low photocatalytic activity limit their practical application. In order to improve on their photocatalytic activities, Copper sulfide-decorated CdS and ZnS (CuS@CdS and CuS@ZnS) nanocomposites were synthesized from Cu(II), Zn(II) and Cd(II) complexes of 2–(phenyl(pyridin–2–yl)methylene)hydrazine–1–carbothioamide, as single source precursors using a facile hot injection method at 250 °C, employing olive oil as capping agent. The structure, morphology, and optical properties of the as-prepared nanocomposites were determined using various analytical techniques. The results of powder X-ray diffraction (p-XRD), energy dispersive X-ray spectroscopy (EDX) and elemental mapping showed the presence of CuS, CdS and ZnS in CuS@CdS and CuS@ZnS, confirming the formation of nanocomposites. Transmission Electron Microscopy (TEM) images show agglomeration of CuS nanoparticles on the surface of CdS and ZnS nanoparticles. Scanning electron microscopy (SEM) images of CuS@CdS and CuS@ZnS nanocomposites revealed an agglomerated flower-like structure with porous surface. The band gap energies of 2.84 eV and 3.12 eV for CuS@CdS and CuS@ZnS, respectively, obtained from Tauc plots, demonstrate that combining CuS with single CdS and ZnS has an effect on their optical properties which probably account for the improved photocatalytic responses. The photocatalytic performance of the as-prepared materials was evaluated using the photodegradation of methylene blue (MB) dye under UV light irradiation. Results show that the degradation efficiencies for CuS@CdS (57 %) and CuS@ZnS (65 %) nanocomposites exhibited higher photocatalytic activity compared to those of pure CuS (42.0 %), CdS (35.1 %) and ZnS (57 %), suggesting that thiosemicarbazone complexes can be used as precursors for the development of metal sulphide nanocomposites as useful photocatalysts for the degradation of organic pollutants.