Transition Electron Microscopy Research Articles

Novel insights into gut health: Cilostazol strengthens gut integrity by adjusting TLR-2/NF-κB/IL-23 and CD44/AKT/GSK-3β/cyclin-D1 trajectories in methotrexate-induced mucositis model

Methotrexate (MTX)-induced gastrointestinal mucositis is a common adverse effect characterized by redox imbalance and overproduction of inflammatory mediators that perturb intestinal integrity. Currently, there is no definitive treatment for this condition and its prevention is still far beyond comprehension. Because of its pleiotropic pharmacological actions, we aimed to explore the potential mechanisms through which cilostazol (CILO) can protect against MTX-induced intestinal mucositis. Wistar rats were allocated into 4 groups, control, CILO (100 mg/kg, p.o for 14 days), MTX (7.5 mg/kg for 4 successive days), and CILO + MTX. The improving effect of CILO on the morphological structure was confirmed by an upturn in the histopathological and transition electron microscope examinations evidenced by the increased jejunal villus height/width and the crypt depth besides the maintenance of tight junctions. These findings were verified biochemically; on the molecular level, CILO reduced the MTX-induced lipid peroxidation, cleaved caspase-3, p53, and the inflammatory parameters (TLR-2, NF-κB, IL-23, TNF-α, IL-1β), while increasing the anti-inflammatory marker IL-10 and the antioxidant enzyme SOD. Moreover, CILO decreased the injurious axis AKT/GSK-3β/cyclin-D1, and CD44+, but increased the immunoexpression of the cell proliferating marker PCNA. CILO also upheld the intestinal barrier by enhancing the tight junction molecules (ZO-1, claudin-4) and the E-cadherin/β-catenin complex while abating the mesenchymal marker vimentin. In conclusion, CILO protected gut integrity by reducing the epithelial-mesenchymal transition process, the MTX-induced oxidative, apoptotic, and inflammatory mediators, and turning off the CD44/AKT/GSK-3β/cyclin D1 trajectory and intensifying the expression of PCNA.

Synthesis of tetrahydrobenzo[a]xanthene-11-ones by indium sulfide nanoparticles as green an efficient and reusable catalyst under solvent-free condition

In this work, tetrahydrobenzo[a]xanthene-11-ones are effectively synthesized without the need for solvents and in an environmentally safe manner by the use of indium sulfide (In2S3) nanoparticle as a catalyst. Indium sulfide (In2S3) nanoparticles were synthesized by the hydrothermal method, and X-ray diffraction pattern (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and transition electron microscopy (TEM) were among the techniques used to characterize indium sulfide (In2S3) nanoparticles. The synthesis of tetrahydrobenzo[a]xanthene-11-ones was achieved in a single pot using a three-component reaction involving β-naphthol, dimedone, and aryl aldehyde. The resultant indium sulfide (In2S3) nanoparticles were produced without the need for a solvent and exhibited remarkable yields, as well as quick reaction times and reusable catalysts.

Development of a novel (Mg0.25Co0.25Ni0.25Zn0.25)O medium entropy oxide for dielectric applications

A novel quaternary medium-entropy rock-salt oxide (Mg0.25Co0.25Ni0.25Zn0.25)O (MERO) was predicted using first-principles calculation and prepared through solid-state reaction. The first-principles study demonstrated that the mixing enthalpy and entropy values of the MERO are 2.377 kJ/mol and 0.693–1.040 R, respectively. The single-phase MERO can be obtained from 1000 °C to 1200 °C, demonstrating good thermal stability, whereas a completely disordered occupancy of different metal cations can be confirmed by Raman spectroscopy. The Transition Electron Microscope (TEM) analysis reveals that the MERO exhibits an FCC structure with a lattice parameter of 4.384 Å. The dielectric permittivity εr of MERO prepared at 1200 °C shows relatively high values of 6.4 × 103 and 18.40 corresponding to frequencies of 100 Hz and 1 MHz at room temperature, exhibiting a potential for application in electrode materials and capacitors.

Divergent Polymer Superstructures from Protonated Poly(adenine) DNA and RNA.

Studies have shown that poly(adenine) DNA and RNA strands protonate at a low pH to form self-associating duplexes; however, the nanoscopic morphology of these structures is unclear. Here, we use Transition Electron Microscopy (TEM), Atomic Force Microscopy (AFM), dynamic light scattering (DLS), and fluorescence spectroscopy to show that both ribose identity (DNA or RNA) and assembly conditions (thermal or room-temperature annealing) dictate unique hierarchical structures for poly(adenine) sequences at a low pH. We show that while the thermodynamic product of protonating poly(adenine) DNA is a discrete dimer of two DNA strands, the kinetic product is a supramolecular polymer that branches and aggregates to form micron-diameter superstructures. In contrast, we find that protonated poly(A) RNA polymerizes into micrometer-length, twisted fibers under the same conditions. These divergent hierarchical morphologies highlight the amplification of subtle chemical differences between RNA and DNA into unique nanoscale behaviors. With the use of poly(adenine) strands spanning vaccine technologies, sensing, and dynamic biotechnology, understanding and controlling the underlying assembly pathways of these structures are critical to developing robust, programmable nanotechnologies.

Real-time monitoring of CdTe quantum dots growth in aqueous solution

Quantum dots (QDs) are remarkable semiconductor nanoparticles, whose optical properties are strongly size-dependent. Therefore, the real-time monitoring of crystal growth pathway during synthesis gives an excellent opportunity to a smart design of the QDs luminescence. In this work, we present a new approach for monitoring the formation of QDs in aqueous solution up to 90 °C, through in situ luminescence analysis, using CdTe as a model system. This technique allows a detailed examination of the evolution of their light emission. In contrast to in situ absorbance analysis, the in situ luminescence measurements in reflection geometry are particularly advantageous once they are not hindered by the concentration increase of the colloidal suspension. The synthesized particles were additionally characterized using X-ray diffraction analysis, transition electron microscopy, UV-Vis absorption and infrared spectroscopy. The infrared spectra showed that 3-mercaptopropionic acid (MPA)-based thiols are covalently bound on the surface of QDs and microscopy revealed the formation of CdS. Setting a total of 3 h of reaction time, for instance, the QDs synthesized at 70, 80 and 90 °C exhibit emission maxima centered at 550, 600 and 655 nm. The in situ monitoring approach opens doors for a more precise achievement of the desired emission wavelength of QDs.

Investigation of Microstructural Properties of Nano-modified Concrete for Sustainable Environment

The creation and evaluation of Nano-modified concrete, with an emphasis on its microstructural characteristics, is the main goal of this extensive study. The inclusion of nanosilica and nanoclay not only enhances the characteristics of concrete but also contributes to mitigating soil pollution. By adding nanosilica and nanoclay as additional cementitious materials, the study intends to assess the structural integrity of nano-modified concrete using cutting-edge techniques like Scanning electron microscopy, Transition electron microscopy and X-ray diffraction. Four different concrete compositions with variable amounts of nanosilica and nanoclay additions (0%, 5%, 10% and 15% of nano additives by weight of fine aggregate) and a 3% cement replacement rate were cast and evaluated throughout the experimental phase. A comparison with regular concrete revealed significant improvements in microstructures, demonstrating the efficacy of nano-modified concrete without sacrificing necessary characteristics. Slump values increased with the addition of nano-silica and nanoclay, indicating better workability and smoother concrete surfaces. The study's findings indicate that the development of Nano-modified concrete has great potential as an advanced building material. In addition to providing instant structural gains, the use of nanosilica and nanoclay enhances the long-term performance of concrete buildings and creates new opportunities for creative and long-lasting building techniques.

CoFe2O4 on Mica Substrate as Flexible Ethanol Gas Sensor in Self-Heating Mode.

In this study, a novel flexible ethanol gas sensor was created by the deposition of a CoFe2O4 (CFO) thin film on a thin mica substrate using the pulsed laser deposition technique. Transition electron microscopy (TEM) investigations clearly demonstrated the successful growth of CFO on the mica, where a well-defined interface was observed. Ethanol gas-sensing studies showed optimal performance at 200 °C, with the highest response of 19.2 to 100 ppm ethanol. Operating the sensor in self-heating mode under 7 V applied voltage, which corresponds to a temperature of approximately 200 °C, produced a maximal response of 19.2 to 100 ppm ethanol. This aligned with the highest responses observed during testing at 200 °C, confirming the sensor's accuracy and sensitivity to ethanol under self-heating conditions. In addition, the sensor exhibited good selectivity to ethanol and excellent flexibility, maintaining its high performance after bending and tilting up to 5000 times. As this is the first report on flexible self-heated CFO gas sensors, we believe that this research holds great promise for the future development of high-quality sensors based on this approach.

New Design PdNi Heterogeneous Nanocatalysts for the Direct Synthesis of Hydrogen Peroxide

Hydrogen peroxide (H2O2) is a widely used chemical as an eco-friendly oxidizing agent, with water being the only byproduct of oxidation in applications like bleaching pulp and paper, making electronic semiconductors, chemical and detergent synthesis, and wastewater treatment. The direct synthesis approach is preferred to provide the environmentally friendly production of H2O2 for market requirements. Bimetallic PdNi nanocatalysts were chosen for this study because of their catalytic activity and the structural characteristics of the material system. First, for the development of order-structured bimetallic PdNi nanocatalysts based on mesoporous carbon template after hydrogen-assisted heat treatment at 750∘C. The transformation of the disordered structure into ordered intermetallically structured PdNi alloys with higher alloying extents was confirmed by X-ray absorption spectroscopy (XAS) and high-resolution transition electron microscopy (HR-TEM). Then, to improve the oxygen oxidation reaction, two-electron pathway selectivity was used by TiO2-C as a support-ordered structure material to facilitate strong metal-support interactions. XAS and X-ray photoelectron spectra (XPS) techniques show more clear evidence of metal-support interactions with electron transfer from defects in the TiO2-C support to the ordered alloyed PdNi nanocatalysts, resulting in record productivity and selectivity of H2O2 production at ambient conditions. The results demonstrated in this study will enlighten a reliable design of new heterogeneous nanocatalysts with ordered structure. Electron transfer between hybrid support and active sites can clarify the catalytic behavior and prompt further research during the direct synthesis of hydrogen peroxide.
 Keywords: hydrogen peroxide, direct synthesis, heterogeneous nanocatalysts PdNi, TiO2-C

Prophylactic nicotinamide treatment protects from rotenone-induced neurodegeneration by increasing mitochondrial content and volume

Leber’s hereditary optic neuropathy (LHON) is driven by mtDNA mutations affecting Complex I presenting as progressive retinal ganglion cell dysfunction usually in the absence of extra-ophthalmic symptoms. There are no long-term neuroprotective agents for LHON. Oral nicotinamide provides a robust neuroprotective effect against mitochondrial and metabolic dysfunction in other retinal injuries. We explored the potential for nicotinamide to protect mitochondria in LHON by modelling the disease in mice through intravitreal injection of the Complex I inhibitor rotenone. Using MitoV mice expressing a mitochondrial-tagged YFP in retinal ganglion cells we assessed mitochondrial morphology through super-resolution imaging and digital reconstruction. Rotenone induced Complex I inhibition resulted in retinal ganglion cell wide mitochondrial loss and fragmentation. This was prevented by oral nicotinamide treatment. Mitochondrial ultrastructure was quantified by transition electron microscopy, demonstrating a loss of cristae density following rotenone injection, which was also prevented by nicotinamide treatment. These results demonstrate that nicotinamide protects mitochondria during Complex I dysfunction. Nicotinamide has the potential to be a useful treatment strategy for LHON to limit retinal ganglion cell degeneration.

Mapping orthorhombic domains with geometrical phase analysis in rare-earth nickelate heterostructures

Most perovskite oxides belong to the Pbnm space group, composed of an anisotropic unit cell, A-site antipolar displacements, and oxygen octahedral tilts. Mapping the orientation of the orthorhombic unit cell in epitaxial heterostructures that consist of at least one Pbnm compound is often needed for understanding and controlling the different degrees of coupling established at their coherent interfaces and, therefore, their resulting physical properties. However, retrieving this information from the strain maps generated with high-resolution scanning transmission electron microscopy can be challenging, because the three pseudocubic lattice parameters are very similar in these systems. Here, we present a novel methodology for mapping the crystallographic orientation in Pbnm systems. It makes use of the geometrical phase analysis algorithm, as applied to aberration-corrected scanning transition electron microscopy images, but in an unconventional way. The method is fast and robust, giving real-space maps of the lattice orientations in Pbnm systems, from both cross section and plan-view geometries, and across large fields of view. As an example, we apply our methodology to rare-earth nickelate heterostructures, in order to investigate how the crystallographic orientation of these films depends on various structural constraints that are imposed by the underlying single crystal substrates. We observe that the resulting domain distributions and associated defect landscapes mainly depend on a competition between the epitaxial compressive/tensile and shear strains, together with the matching of atomic displacements at the substrate/film interface. The results point toward strategies for controlling these characteristics by appropriate substrate choice.

Tuning the superconducting performance of YBa2Cu3O7-δ films through field-induced oxygen doping.

The exploration of metal-insulator transitions to produce field-induced reversible resistive switching effects has been a longstanding pursuit in materials science. Although the resistive switching effect in strongly correlated oxides is often associated with the creation or annihilation of oxygen vacancies, the underlying mechanisms behind this phenomenon are complex and, in many cases, still not clear. This study focuses on the analysis of the superconducting performance of cuprate YBa2Cu3O7-δ (YBCO) devices switched to different resistive states through gate voltage pulses. The goal is to evaluate the effect of field-induced oxygen diffusion on the magnetic field and angular dependence of the critical current density and identify the role of induced defects in the switching performance. Transition electron microscopy measurements indicate that field-induced transition to high resistance states occurs through the generation of YBa2Cu4O7 (Y124) intergrowths with a large amount of oxygen vacancies, in agreement with the obtained critical current density dependences. These results have significant implications for better understanding the mechanisms of field-induced oxygen doping in cuprate superconductors and their role on the superconducting performance.

Structural characterization, optical, and magnetic properties of MgTbxFe2−xO4 nano ferrite particles using a combustion technique

The citrate gel auto-combustion method was utilised to synthesis terbium-doped nanoparticles (NP) with considerable concentrations of magnesium ferrites, using the chemical formula MgTbxFe2−xO4 and an X range of 0.000 to 0.0030 (with an X step of 0.0005). At 300 K, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transition electron microscopy (TEM), and magnetic characteristics were all determined. The XRD and TEM images indicate nanoscale ranges as well as the cubic spinel structure, which is merely phased, and confirm the normal crystallite size. The lattice parameter and volume decrease as density increases with doping of terbium. The images from the FESEM. It is evident that the grain clusters were found within the material. In the specimen's case, the highly interacting grains were found. The fourier-transformed infrared spectroscopy (FTIR) data clearly suggests that two metallic bands have formed, confirming the cubic spinel ferrites. There are two primary absorption bands visible between 200 and 650 cm−1. The UV–vis investigation demonstrates that the calculated direct band gap energy values have a violet shift. The band gab energy was reported in the range of 415.30 eV to 375.12 eV.The magnetic properties of the hysteresis loops indicate a transition from hard magnetic moments to soft magnetic moments. All magnetic properties were reduced when the Tb3+ ion was substituted. They are excellent for switching memory storage devices as well as telecommunications.

Non-Noble Transition Metal-Based Electrocatalysts for Green Hydrogen Production from Anion Exchange Membrane (AEM) Seawater Electrolyzer

As water-scarce is increasing rapidly all over the world, water electrolysis might not be a practical approach for sustainable hydrogen production in the long term. Fortunately, hydrogen production from the anion exchange membrane (AEM) seawater electrolysis enables to achieve of sustainability and durability. But still, suitable electrocatalysts for hydrogen and oxygen evolution reactions in seawater are not figured out yet. Here we report non-noble transition metal-based electrocatalysts for hydrogen and oxygen evolution reaction in seawater electrolysis. The synthesized electrocatalysts were in-situ characterized in X-ray diffraction (XRD), scanning electron microscopy (SEM), Transition electron microscopy (TEM), Raman spectroscopy, and ex-situ characterized in linear sweep voltammetry (LSV), Chronopotentiometry, and impedance studies. Further, the electrocatalysts were investigated in a single-cell anion exchange membrane electrolyzer, and polarization curves, stability tests, and efficiency calculations were carried out. These research findings will be further investigated until attains the industrially required parameters of 1 A cm-2 at a low overpotential of 1.8 V.

Application of electrochemical sensor modified by SBA-15 /Fe3O4/polyaniline nanocomposite for determination of tyrosine in milk samples

In this study, a selective SBA-15 /Fe3O4/Polyaniline /Chitosan nanocomposite was successfully electrodeposited on Screen- Printed Carbon Electrode (SPCE) and used for L-Tyrosine (Tyr) detection.Biological diagnostic probes such as artificial receptors are one of the important diagnostic layers for the identification of vital biomolecules, including essential amino acids like Tyr. A new electrochemical sensing platform based on differential pulse voltammetry was prepared for selective determination of Tyr in milk samples.SBA-15 nanoparticles were synthesized from corn leaves as a source of silica. These high-absorbance nanoparticles have been used for surface modification of SPCE. The morphology and electrochemical performance of the modified electrode were characterized by X-ray diffraction, scanning electron microscopy (SEM), transition electron microscopy (TEM), Furrier transform infrared spectroscopy (FTIR), Brunauer-Emmett–Teller techniques, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry(CV).As a novel modified electrode, the catalytic activity of the modified SPCE towards electro-oxidation of Tyr was measured by differential pulse voltammetry (DPV). The experimental conditions, including the adsorption time, scan rates, the ratio of SBA-15, pH value, and applied potential, are investigated in detail.Electrochemical sensor based on SBA-15 (SPCE/SBA-15/Fe3O4/Polyaniline /Chitosan) Compared with SPCE/Fe3O4/Polyaniline/Chitosan shows good sensitivity, repeatability, reproducibility, low detection limit and high selectivity.In addition, a linear correlation between oxidation peak current and concentration of Tyr in the ranges 0.1–250 μM with a detection limit of 0.05 μM (S/N = 3) was obtained. Eventually, the suggested sensor was used for quantification of Tyr in real samples, by adding standard solutions to the milk samples.

Preparation, Characterization, and Antibacterial Properties of Cu-Fibreboards

In the present study, copper modified fibreboards were prepared and their existing phase, morphology, and antibacterial behaviour were investigated. The copper content and the physical and mechanical properties of fibreboards (thickness, bending strength, and swelling) were determined. X-ray diffraction analysis (XRD) showing diffraction peaks typical for cellulose, Cu2S, and Na2SO4, depended on the preparation conditions. The average size of the Cu2S crystals varied between 20 and 50 nm. The morphology of the obtained fibreboards, as well as the size and shape of copper particles, were observed by scanning electron microscopy (SEM) and transition electron microscopy (TEM). The antibacterial activity was tested against Gram-positive (Bacillus subtilis 3562) and Gram-negative (Escherichia coli K12 407) bacteria. The tests showed that the materials had higher antibacterial activity against E. coli, which depended on their preparation conditions. Based on these results, the obtained copper fibreboards can be used as antibacterial agents in the packaging and building industry.

Reduced Graphene Oxide-Supported Iron-Cobalt Alloys as High-Performance Catalysts for Oxygen Reduction Reaction.

Exploring non-precious metal-based catalysts for oxygen reduction reactions (ORR) as a substitute for precious metal catalysts has attracted great attention in recent times. In this paper, we report a general methodology for preparing nitrogen-doped reduced graphene oxide (N-rGO)-supported, FeCo alloy (FeCo@N-rGO)-based catalysts for ORR. The structure of the FeCo@N-rGO based catalysts is investigated using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and transition electron microscopy, etc. Results show that the FeCo alloy is supported by the rGO and carbon that derives from the organic ligand of Fe and Co ions. The eletrocatalytic performance is examined by cyclic voltammetry, linear scanning voltammetry, Tafel, electrochemical spectroscopy impedance, rotate disc electrode, and rotate ring disc electrode, etc. Results show that FeCo@N-rGO based catalysts exhibit an onset potential of 0.98 V (vs. RHE) and a half-wave potential of 0.93 V (vs. RHE). The excellent catalytic performance of FeCo@N-rGO is ascribed to its large surface area and the synergistic effect between FeCo alloy and N-rGO, which provides a large number of active sites and a sufficient surface area.

Constructing Chiral Covalent-Organic Frameworks for Circularly Polarized Light Detection.

The use of chiral covalent organic frameworks (COFs) as active elements in photodetectors to directly identify circularly polarized light (CPL) can meet the requirement of integration and miniaturization of the as-fabricated devices. Herein, the design and synthesis of two isoreticular chiral two-dimensional (2D) COFs (CityU-7 and CityU-8) by introducing photosensitive porphyrin-based amines (5,10,15,20-tetrakis(4-aminophenyl)porphyrin) to enhance the optical absorption and chiral aldehyde linkage (2,5-bis((S/R))-2-methylbutoxy)terephthalaldehyde) to engender chirality for direct CPL detection are reported. Their crystalline structures were confirmed by powder X-ray diffraction, Fourier-transform infrared spectroscopy, and low-dose transition electron microscopy. Employing both chiral COFs as the active layers in photodetectors, left-handed circularly (LHC) and right-handed circularly (RHC) polarized light at 405nm can be well distinguishable with short response time, high responsivity, and satisfying detectivity. The study provides the first example on the design and synthesis of chiral COFs for direct detection of CPL.

Microwave-assisted sol–gel synthesis of V-TiO2 nanocatalyst for wastewater treatment

A microwave (MW)-assisted sol–gel approach was used to create a new vanadium-doped titanium dioxide (V-TiO2) nanocatalyst. When compared to synthesized titanium dioxide, the doped V-TiO2 nanocatalyst had higher photocatalytic activity than the synthesized titanium dioxide (TiO2). The doped V-TiO2 absorption edge shifted, increasing the visible-light absorption capability of the nanocatalyst. The optical absorbance of doped V-TiO2 had a lower bandgap energy (Eg) of 2.35 eV than TiO2, which band gap energy was observed as 2.9 eV. In its crystalline form, the doped nanocatalyst inherited morphological and structural compositions that portrayed both anatase and rutile lattice fringes. This study agreed well with the results obtained from the X-ray diffraction (XRD) analysis. Image from scanning electron microscope (SEM) and transition electron microscope (TEM) morphological characterization depicted a cluster made up of non-uniform spherical aggregate particles with particle sizes of between 15 and 50 nm. The presence of V, Ti, and O constituents in the catalyst is confirmed by an Energy Dispersive Spectrometer (EDS). Brunauer-Emmett-Teller (SBET) investigation displays a surface area of produced TiO2, as 102.75 m2/g, while V-TiO2 was 113. 83 m2/g. Under visible light irradiation, doped V-TiO2 demonstrated excellent photocatalytic activities. Within the first 15 min, the degradation of a model pollutant (Methylene blue) was achieved. The impact of doping TiO2, demonstrated an increase in V-TiO2 photocatalytic activity, with excellent rates of removal and a well-anticipated decrease energy band gap.

Correlation of morphology, rheology, thermal, and mechanical properties in PP/EOC blends in presence of nanoclay and compatibilizer

ABSTRACT To expand the range of applications and overcome mechanical limitations of Polypropylene (PP), a commonly used industrial polymer, toughness modification is required. In this study, PP was toughened with ethylene octene copolymer (EOC) and nanoclay platelets and the blends and nanocomposites of PP/EOC were prepared by means of a melt mixing process, and the effect of different grades of EOC, the addition of nanoclay platelets, and the effect of compatibilizer on properties of the final system were investigated. Scanning and transition electron microscopy, X-ray diffraction, rheology, differential scanning calorimetry, and dynamic-mechanical analysis were conducted to correlate the structure to the resulting properties. The results indicate that different grades of EOC with different molecular weights and viscosity can have a tremendous impact on droplet size and final properties of the blend sample. From a morphological point of view, the addition of EOC grade with higher viscosity (ƞi) in PP/EOC blends results in droplet matrix structure with larger EOC droplets. To decrease the droplet size, and hence improvement in final properties, nanoclay and compatibilizer were introduced to the blend. According to the results, selective localization of nanoclay and proper dispersion degree of nanoclay in the PP/EOC blend with higher viscosity grade of EOC containing nanoclay up to 3 wt.% lead to amelioration of the final properties of the system including complex viscosity, storage modulus, damping, and crystallinity. Moreover, the addition of the compatibilizer to the nanocomposite samples with 5 wt.% nanoclay can compensate for the deteriorated properties which occurred as a result of nanoclay aggregation in this system. This indicates that the addition of the nanoclay and compatibilizer plays an important role in toughening, morphology, and determining the final properties of the system as well.

Synthesis and characterization of amorphous nano silica from South African coal fly ash

In this study, amorphous silica nanoparticle was extracted from South African coal fly ash (SACFA), using a facile sol–gel synthesis method. Prepared amorphous silica nanoparticles (ASNPs) were characterized employing X-ray fluorescence (XRF) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), transition electron microscope (TEM), Brauer Emmett Teller (SBET) surface area analysis, and ultraviolet–visible diffuse reflection spectroscopy (UV–vis DRS). XRF analysis suggests SACFA as fly ash class F. the XRD pattern, reveals the structural compositing of SACFA and the amorphous nature of extracted SNP, while the FTIR assay shows the presence of silanol and siloxane groups. SEM and TEM analysis revealed primary silica nanoparticles were roughly spherical with sizes of about 98 nm. EDX spectral confirms the presence of SiO2. The findings of this study demonstrate a simple sol–gel method of synthesizing amorphous nano silica from SACFA, thus suggesting the utilization of SACFA in high-tech and complex material preparation and applications in a more inventive manner.