Search

In the present study, silver nanoparticles were synthesized via green synthesis using fenugreek (Trigonella foenum‐graecum L.) seeds of variety HM 425. The AgNPs were characterized by using UV‐Visible spectroscopy, Particle size analyzer, Field emission scanning electron microscopy coupled to Energy dispersive X‐ray spectroscopy, XRD, High resolution transmission electron microscopy and Fourier Transform Infrared Spectroscopy. The AgNPs were spherical and had an average particle size of 28 nm. The reduction of cationic dyes Methylene blue, Rhodamine B, and an anionic azo dye Methyl Orange by Sodium borohydride was used as a model reaction to investigate the catalytic ability of AgNPs. The results demonstrated an efficient catalytic dye degradation of methylene blue (95.81 %, 25 min, 0.1737±0.01 min−1), Rhodamine B (90.23 %, 15 min, 0.1388±0.01 min−1) and methyl orange (83.63 %, 39 min, 0.0412±0.002 min−1). The synthesized AgNPs had an excellent detection limit of 12.50 μM for Hg2+, making them excellent solid bio‐based sensors for mercury sensing. [ABSTRACT FROM AUTHOR]

In the present study, silver nanoparticles were synthesized via green synthesis using fenugreek (Trigonella foenum‐graecum L.) seeds of variety HM 425. The AgNPs were characterized by using UV‐Visible spectroscopy, Particle size analyzer, Field emission scanning electron microscopy coupled to Energy dispersive X‐ray spectroscopy, XRD, High resolution transmission electron microscopy and Fourier Transform Infrared Spectroscopy. The AgNPs were spherical and had an average particle size of 28 nm. The reduction of cationic dyes Methylene blue, Rhodamine B, and an anionic azo dye Methyl Orange by Sodium borohydride was used as a model reaction to investigate the catalytic ability of AgNPs. The results demonstrated an efficient catalytic dye degradation of methylene blue (95.81 %, 25 min, 0.1737±0.01 min−1), Rhodamine B (90.23 %, 15 min, 0.1388±0.01 min−1) and methyl orange (83.63 %, 39 min, 0.0412±0.002 min−1). The synthesized AgNPs had an excellent detection limit of 12.50 μM for Hg2+, making them excellent solid bio‐based sensors for mercury sensing. [ABSTRACT FROM AUTHOR]

Transmission electron microscopy (TEM) has evolved into a powerful characterization tool that allows visualization of materials with finer resolution than any other type of microscope in existence. While numerous areas of the physical and biologically sciences and engineering benefit tremendously from TEM and its analytical features, the highest resolution can only be achieved if a sample fulfills certain requirements, including an optimal thickness as well as a sufficiently long e‐beam stability. At a fundamental level, the physical and chemical properties of organic polymers are generally problematic in conjunction with TEM, as they experience damage from the electron beam more readily than their hard materials counterparts. However, progress in polymer characterization using TEM has evolved considerably and the polymer community stands to benefit greatly from continued growth going forward. [ABSTRACT FROM AUTHOR]

Polyaniline‐potassium doped nickel oxide nanocomposites (PANI/KNO) were efficiently synthesized via an in situ chemical oxidation method, meticulously confirmed by comprehensive x‐ray diffraction, Fourier transformation infrared spectroscopy, energy dispersive x‐ray spectroscopy, selected area electron diffraction, and x‐ray photoelectron spectroscopy analyses. The crystallite size and strain exhibited distinct behaviors, while field emission scanning electron microscopy revealed a blend of irregular spherical shapes and nanofibers, further confirmed by high resolution transmission electron microscopy. These composites exhibited significantly enhanced thermal stability, surpassing PANI by 1.39 times, and showcased a band gap exceeding 3 eV, along with multiple photoluminescence peaks at room temperature (RT). Moreover, their RT AC conductivity experienced a remarkable surge by 4.91 times compared to pure polyaniline. Jonscher's Power Law model and the Havriliak–Negami relaxation model are employed to elucidate the electrical properties of composite materials. The composites displayed nonDebye relaxation behavior with increased conductivity, as observed through impedance analysis, electrical modulus evaluation, and dielectric constant assessment. Additionally, evident superparamagnetic properties and multiple magnetic domains further contributed to their effectiveness. The PANI/KNO composite demonstrated photocatalytic efficiency, achieving over 90% degradation of methylene blue dye across four cycles, thus highlighting its superior photostability. Furthermore, investigations into its response to pH variations and scavenger activity underscored its immense potential for highly effective photocatalytic applications. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) are a new type of carbon nanomaterial that has recently attracted great attention as a potential competitor to standard semiconductor quantum dots. There are various ways to synthesis CQDs, and one of harmless way is undoubtedly green synthesis. In this study, hydrothermal synthesis based on the green way was employed to synthesize CQDs. The CQDs were obtained using the green leaves of the Stachys euadenia plant extract, an endemic species located in Turkey. The CQDs were characterized by fluorescent and UV‐Visible spectroscopy, and results confirmed blue emission (430–480 nm) and absorption around 280 nm. X‐ray photoelectron spectroscopy (XPS) analysis revealed C=C, C–N and C–O interactions. X‐ray diffractometer (XRD) patterns confirmed structure of carbon with a broad peak of (002) plane. High resolution tunneling electron microscopy (HRTEM) and dynamic light scattering (DLS) analysis was used to determine the shape and size of CQDs. The CQDs obtained from Stachys euadenia were employed as electrode materials for capacitor application, and they were tested in Swagelok‐type cell by cyclic voltammetry (CV) measurements. CQD capacitors exhibited 2.12 F/g charge and 1.24 F/g discharge capacitances were obtained with ~58% coulombic efficiency rate for the first cycle. Results highlights that CQDs are synthesized successfully by green synthesis method and can be used for capacitor applications. [ABSTRACT FROM AUTHOR]

The controlled synthesis of two‐dimensional nanocrystals of graphene particles instead of amorphous carbon quantum dots is highly challenging and requires tremendous efforts to optimize the reaction conditions. It has been observed that as a significant bio‐compatible zero‐dimensional material, graphene quantum dots are considered as a novel material for opto‐electronics, energy, biological and environmental applications. However, very few are known about their utilization in photocatalytic degradation of pesticides, especially organochlorine pesticides which are resistant to removal by conventional wastewater treatment methods. In this work, graphene quantum dots were produced from rice husk at relatively low temperatures, resulting in an average particle size of 3.3 nm. The high resolution transmission electron microscopy clearly showed the formation of spherical quantum dots having lattice fringes and the selected area electron diffraction pattern showed the crystallinity of the graphene quantum dots. A study of photodegradation of three highly toxic organochlorine pesticides namely, dichlorodiphenyl trichloro ethane, cypermethrin and fenvalerate were carried out using as‐synthesized graphene quantum dots from rice husk. Interestingly, all these pesticides were found to be degraded around 60 % to 70 % under visible light conditions. It confirmed that synthesized graphene quantum dots from rice husk can act as prominent photocatalyst for the degradation of pesticides and other pollutants. [ABSTRACT FROM AUTHOR]

Biodiesel has recently emerged as a renewable and environmentally benign fuel substitute for fossil‐derived energy sources. The use of heterogeneous solid catalysts for the generation of biodiesel from biomass‐derived fats and oils is sustainable. Among various reported catalyst supports, metal–organic frameworks (MOFs) have been popular choices for enhancing catalytic activity for biodiesel synthesis because of several outstanding features including porosity, high surface area, adjustable structures, and uniform pore sizes. In this research, the authors synthesized a novel nanocomposite of MOF‐supported hydroxyapatite (UiO‐66@HAp) using a facile impregnation technique and the characterization of the as‐synthesized catalyst was performed by different spectroscopic methods including powder X‐ray diffraction (PXRD), Fourier transform infrared (FTIR), X‐ray photoelectron spectroscopy (XPS), field emission gun‐scanning electron microscope (FEG‐SEM), energy dispersive X‐ray spectroscopy (EDS), high resolution transmission electron microscopy (HR‐TEM), thermogravimetric analysis (TGA), and N2 adsorption–desorption techniques. After successful synthesis, the catalytic property of the prepared material was evaluated in the palm oil transesterification into biodiesel. Product formation was confirmed by the 1H nuclear magnetic resonance (NMR) spectroscopy, 13C NMR, FTIR, and gas chromatography–mass spectrometry (GC–MS) of the biodiesel. The influence of different reaction variables such as catalyst dosage, methanol/oil molar ratio, temperature of the reaction, and reaction time was also studied. The outcomes revealed that the maximum biodiesel yield (∼97%) was obtained when 6 wt% catalyst was used with a 6:1 ratio of methanol/oil at 70 °C for 1 h. It was also observed that, even after 5 cycles of reuse, the catalyst was capable of producing significant amounts of biodiesel (over 90%). The results suggest that the synthesized novel catalyst holds a promising future in the sustainable production of biodiesel. [ABSTRACT FROM AUTHOR]

This article discusses the use of high-resolution scanning electron microscopy to image the structural organization of the LINC complex cage at the nuclear envelope. The LINC complex is a group of proteins that connect the cytoskeleton to the nucleus, playing a crucial role in controlling nuclear deformability and integrity during cell migration. The study aims to directly image the structure of the LINC complex and its interactions with the nuclear envelope. The results provide preliminary evidence of a network of filaments that connect the cytoplasmic cytoskeleton to the outer nuclear membrane and embed in the inner nuclear membrane. The study also highlights the importance of sample preparation techniques and the use of immunogold labeling for imaging. The author, Lakshana Baheerathan, gained valuable technical and transferable skills through this research project and plans to continue studying cell biology and microscopy in future projects. [Extracted from the article]

The water‐splitting reaction via electrocatalyst is a potential method for hydrogen evolution reaction (HER), and metal‐free electrocatalytic material with excellent performance are in great demand for future applications. In this context, a novel, facile, and efficient route for the synthesis of highly conjugated azomethine‐functionalized graphitic carbon nitride (GCN) is proposed. The GCN functionalized with azomethine moiety by using various proportions of GCN–x% dimethyl amino cinnamaldehyde (DMAC) (x = 0.1%, 0.5%, 1.0%, 5.0%, and 10.0%) of p‐DMAC leads to introduction of azomethine moiety onto the GCN matrix that does not affect the original framework of GCN network, but it efficiently enlarges its π‐delocalized system, increases its surface area, and enhances the electrocatalytic properties. All the structural and morphological properties of synthesized materials are analyzed by X‐ray diffraction, Fourier transform infrared, X‐ray photoelectron spectroscopy, Brunauer–Emmett–Teller, High resolution transmission electron microscopy, and field emission scanning electron microscopy, with Energy dispersive spectroscopy analysis. Furthermore, the GCN–5.0% DMAC exhibits superb HER performance with onset potential near to 0 V, and a low overpotential of 18.7 mV at 5 mA cm−2, and extremely ultrasmall Tafel slope (46.8 mV dec−1) in an 0.5 m H2SO4. In this study, the door is laid for interfacial engineering to be used as an efficient method for economically developing electrocatalysts. [ABSTRACT FROM AUTHOR]

Many researchers have shifted their interest towards eco‐friendly, cost effective, and environmental‐based metal oxide nanoparticles. Herein, Cu2O nanoparticles are synthesized via green method for water splitting application. The prepared materials are characterized structurally and morphologically by field emission‐scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X‐ray photoelectron spectroscopy (XPS) Raman, and UV–visible spectroscopy. It is found that size and morphology depend strongly on OLE concentration and reaction time. The temperature increase leads to the formation of copper oxide (CuO) nanoparticles, which exhibit quantum confinement behavior and have an optical band gap that increases with decreasing size. Photoelectrochemical (PEC) tests of the coated graphite with Cu2O nanoparticles show a severe instability of Cu2O under irradiation due to the oxidation state that can easily change. For that, a protective overlayer of cuprous sulfide Cu2S is successfully grown on the top of Cu2O nanostructures to stabilize the photocathode. After Cu2S deposition, the measured photocurrent is significantly improved. Thus, this material is very promising for hydrogen generation by water splitting. [ABSTRACT FROM AUTHOR]

The present study was focused on green synthesis of Silver nanoparticles (AgNPs) using Trigonella foenum‐graceum L. seed extract belonging to specific variety HM (Hisar Mukta) 425, optimizing the different experimental conditions required for the formation and stability of AgNPs. UV‐Vis spectroscopy, Particle Size Analyzer (PSA), Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscopy (HRTEM), X‐ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) were used to characterise the synthesised AgNPs. The average size of AgNPs was found to be 22 nm and were spherical in shape. Additionally, the United States Environmental Protection Agency (USEPA) has listed nitrophenols as a priority pollutant, and biosynthesized AgNPs can catalytically convert them into less harmful aminophenols. One example of a reaction where AgNPs are used as a catalyst is the conversion of p‐nitrophenol to p‐aminophenol, which acts as a bridge for many analgesics and antipyretic medications. Hence, the study is anticipated to have a significant impact on the pharmaceutical, cosmetic, and food industries. [ABSTRACT FROM AUTHOR]

Environmental remediation projects are becoming increasingly interested in polymers, transition‐metal oxides and graphene based nanocomposites as photocatalysts. To increase their effectiveness, they could be adjusted in conjunction with one another. A hierarchically organised nanocomposite of reduced graphene oxide based TiO2 and copolymer (Aniline and Indole) (rGO/ TiO2/P(ANI‐co‐IN)), TiO2/P(ANI‐co‐IN) and P(ANI‐co‐IN) has been synthesized by heterogeneous emulsion polymerization and is used as a catalyst for the degradation of the cationic Rhodamine (RhB) dye. Different analyses were used to characterize the resulting nanocomposites i. e. UV‐Vis diffuse reflectance spectra (DRS), Fourier Transform Infrared spectroscopy (FTIR), X‐ray diffraction (XRD), Energy Dispersive X‐Ray Spectroscopy (EDX), High Resolution Transmission electron microscopy (HR‐TEM), Selected area (electron) diffraction (SAED) and thermogravimetric analysis (TGA). DRS results revealed that the rGO/ TiO2/ P(ANI‐co‐IN) nanocomposites band gap decreased when compared to TiO2/P(ANI‐co‐IN) and P(ANI‐co‐IN). Here, rGO/ TiO2/P(ANI‐co‐IN) has outperformed every previous study on polymer/metal oxide/graphene‐based ternary nanocomposites, achieving 92 % RhB degradation within 80 min with a degradation rate constant of 0.032 min−1. The reusability of rGO/ TiO2/P(ANI‐co‐IN) was run over five cycles which bought in only a small change which could be negligible. Overall, this research may make it easier to synthesise hierarchically organised ternary nanocomposites in the future, which might be used to improve photocatalysis and address environmental protection challenges. [ABSTRACT FROM AUTHOR]

With an aim to combine the catalytic properties of Pd nanoparticles (NPs) with the excellent characteristics of porous layered double hydroxides (LDH), in the present study, four different catalysts (Pd/Fe3O4‐CoTiMgAlLDH, Pd/Fe3O4‐CoTiMgLDH, Pd/Fe3O4‐CoTiAlLDH and Pd/Fe3O4‐CoTiLDH) were synthesized by supporting Pd NPs onto four different Fe3O4‐LDH supports, which were synthesized by varying the metals in LDH. The catalytic activity of these catalysts was studied for Suzuki coupling and reductive degradation of dyes. Pd/Fe3O4‐CoTiMgLDH outperformed the other catalysts in both reactions. The synthesized catalysts were examined via different characterization techniques like X‐ray diffraction (XRD), Brunauer–Emmett–Teller analysis (BET), X‐ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), high resolution transmission electron microscopy (HR‐TEM), field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray (EDX), energy dispersive X‐ray mapping (SEM–EDX mapping), inductively coupled plasma atomic emission spectroscopy (ICP‐AES) and vibrating sample magnetometry (VSM). On the basis of results obtained from XPS and the experimental data, Fe3O4‐CoTiMgLDH was found to be the support of choice as it not only stabilized the Pd0 NPs but also increased the electron density on the anchored Pd0 species, which enhanced the catalytic activity of Pd/Fe3O4‐CoTiMgLDH for studied organic transformations. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenide (TMDC) nanotubes complement the field of low‐dimensional materials with their quasi‐1D morphology and a wide set of intriguing properties. By introducing different transition metals into the crystal structure, their properties can be tailored for specific purpose and applications. Herein, the characterization and a subsequent preparation of single‐nanotube field emission devices of MoxWx‐1S2 nanotubes prepared via the chemical vapor transport reaction is presented. Energy‐dispersive X‐ray spectroscopy, Raman spectroscopy, and X‐ray diffraction indicate that the molybdenum and tungsten atoms are randomly distributed within the crystal structure and that the material is highly crystalline. High resolution transmission electron microscopy and electron diffraction (ED) patterns further corroborate these findings. A detailed analysis of the ED patterns from an eight‐layer nanotube reveal that the nanotubes grow in the 2H structure, with each shell consists of one bilayer. The work function of the nanotubes is comparable to that of pure MoS2 and lower of pure WS2 NTs, making them ideal candidates for field emission applications. Two devices with different geometrical setup are prepared and tested as field emitters, showing promising results for single nanotube field emission applications. [ABSTRACT FROM AUTHOR]

Metal sulfides have shown great promise for sodium‐ion batteries due to their excellent redox reversibility and relatively high capacity. However, metal sulfides generally suffer from sluggish charge transport and serious volume change during the charge–discharge process. Herein, potato chip‐like nitrogen‐doped carbon‐coated ZnS/Sb2S3 heterojunction (ZnS/Sb2S3@NC) is precisely synthesized through a sulfurization reaction, and a subsequent metal cation exchange process between Zn2+ and Sb3+. The theoretical calculations and experimental studies reveal the boosted charge transfer in ZnS/Sb2S3@NC composites. Therefore, the ZnS/Sb2S3@NC electrode exhibits excellent cycling stability (a high reversible capacity of 511.4 mAh g‐1 after 450 cycles) and superior rate performance (400.4 mAh g‐1 at 10 A g‐1). In addition, ZnS/Sb2S3@NC is based on a conversion‐alloy reaction mechanism to store Na+, which is disclosed by the X‐ray diffraction and high resolution transmission electron microscopy analysis. This effective synthesis method can provide a reference for the design of other high‐performance electrode materials for sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Low loading Pton TiO2 were prepared by an impregnation‐reduction process for chemoselective hydrogenation of chloronitrobenzenes (CNBs) to chloroanilines (CANs). The structure and physicochemical properties were characterized by N2 adsorption‐desorption, X‐ray diffraction, high resolution transmission electron microscopy, X‐ray photoelectron spectroscopy and temperature programmedreduction. The low loading Pt(≤0.08 wt %) on TiO2 exhibited outstanding chemoselectivity for the catalytic hydrogenation of CNBs to CANs, without any disturbance on carbon‐chlorine bond. The characterization data suggested that the Pt particles were highly dispersed on TiO2 and strongelectronicinteractionsoccur between the dispersedPt andTiO2support, which led toelectron deficiency of nearly all Pt and production of suboxide TiOx species (x<2) in the 0.08 wt % Pt/TiO2. The electron‐deficient Pt and suboxide TiOx species favor N=O bondactivation, leading to its unique chemoselectivity. [ABSTRACT FROM AUTHOR]

Ni nanoparticles (NiNPs) were prepared by thermal decomposition of nickel acetylacetonate in the presence of a third generation polypyridylphenylene dendrimer (G3) which acts both as a coordinating ligand due to presence of pyridine groups and as a stabilizing agent due to highly branched architecture. Transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), and X‐ray photoelectron spectroscopy (XPS) were used to extensively evaluate structure and morphology of the synthesized NiNPs@G3. The selected area electron diffraction (SAED) allowed us to conclude about fcc structure of NiNPs while STEM EDS analysis demonstrated a formation of core‐shell NiO@Ni NPs. Further, the catalyst was tested in selected Suzuki‐Miyaura cross‐coupling reactions at mild conditions and demonstrated a high efficiency at low Ni loading with negligible content of Ni0 on the NP surface. The functional hyperbranched dendrimer macromolecule provided an excellent stabilization for NiNPs@G3 while allowing an easy access for reactants to catalytic sites. The high activity of the catalyst in the recycling experiments was maintained by the absence of Ni leaching from the NiNPs@G3. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms that connect heat and electron transport with crystal structures and defect chemistry is fundamental to develop materials with thermoelectric properties. In this work, we synthesized a series of self‐doped compounds Cu2+xMn1−xGeS4 through Cu for Mn substitution. Using a combination of powder X‐ray diffraction, high resolution transmission electron microscopy and precession‐assisted electron diffraction tomography, we evidence that the materials are composed of interconnected enargite‐ and stannite‐type structures, via the formation of nanodomains with a high density of coherent interfaces. By combining experiments with ab initio electron and phonon calculations, we discuss the structure–thermoelectric properties relationships and clarify the interesting crystal chemistry in this system. We demonstrate that excess Cu+ substituted for Mn2+ dopes holes into the top of the valence band, leading to a remarkable enhancement of the power factor and figure of merit ZT. [ABSTRACT FROM AUTHOR]

A novel 2‐D flakes like Al‐BPED ((N1,N2‐bis [pyridine‐2‐yl]methyl)ethane‐1,2‐diamine) metal–organic framework (MOF) have been explored for its catalytic potential in the N‐alkylation of amines with dialkyl carbonates. The Al‐BPED MOF catalyst has been synthesized by hydrothermal route. The X‐ray diffraction, Fourier Transform Infrared Spectroscope (FTIR), and High Resolution Transmission Electron Microscopy (HRTEM) images were used to analyze the morphology of the synthesized Al‐BPED MOF samples. With the use of Al‐BPED MOF, the primary and secondary aromatic amines were selectively and efficiently methylated with dimethyl carbonate. The effect of process conditions has been investigated toward N‐methylation, N‐ethylation, and N‐benzylation of aromatic amines. Under the optimal conditions with 10 mol% of the MOF catalyst, a maximum aniline conversion of 88% and a selectivity >90% toward N‐alkylation was achieved. The kinetic studies revealed the N‐alkylation reaction in presence of Al‐BPED MOF followed pseudo‐first order rate kinetics. [ABSTRACT FROM AUTHOR]

Glassy carbon is frequently used in electrochemical research due to its presumed robust electrochemical performance. Although it is widely utilized as a rotating disc electrode material, the modification of glassy carbon during electro‐catalytic process is rarely emphasized or characterized. In this report, we investigated the structural modification of glassy carbon imparted by electrochemical oxidation in acidic media and compared the behavior with graphite. The functional groups generated from electrochemical oxidation in both electrodes possess similar electrochemical properties. However, above an oxidation potential of 1.8 V (vs. reversibly hydrogen electrode), glassy carbon exhibits a lower electrochemical capacitance compared to graphite. We propose that the existence of electrochemically inactive species, originating from the non‐graphitic portion of glassy carbon is attributed to such deterioration. Additionally, high resolution scanning electron microscopy (HR‐SEM) and high‐resolution transmission electron microscopy (HR‐TEM) images corroborate how electrochemical oxidation prevails for glassy carbon electrodes at oxidative potentials. The overall analysis leads us to propose a corrosion mechanism for glassy carbon in acidic solution. [ABSTRACT FROM AUTHOR]

The development of bimetallic and magnetic nanomaterials as a catalyst is highly desirable for organic transformations due to their recyclability for the sustainable future of chemical industries. Bimetallic CoNi nanoflowers were developed via the facile liquid‐phase reduction method and were employed for the hydrogenation of terminal alkynes. The structural and morphological studies were analyzed by X‐ray diffraction, Field‐Emission Scanning Electron Microscopy, and High Resolution Transmission Electron Microscopy. The bimetallic CoNi nanoflower exhibited 100 % conversion with ∼100 % selectivity towards alkane products with recyclability up to six cycles. The transfer hydrogenation mechanism was proposed via diimide formation with Co(0)/Ni(0) state, confirmed by X‐ray Photoemission Spectroscopy analysis. [ABSTRACT FROM AUTHOR]

Because of its weak durability at low temperatures and low strain rates, polypropylene's use as an engineering plastic is restricted. To make polypropylene more tougher, combine it with elastomeric particles in a cost‐effective manner is an excellent option. Internal melt blending was used to manufacture polypropylene (PP) and high‐molecular‐grade ethylene‐propylene‐diene rubber (EPDM) blends with varying constitutive ratios in this work. EPDM's lower portions have especially high impact strength ratings for PP/EPDM mixtures. (i.e., 2.5, 5, and 7.5 parts per hundred EPDM rubber). The mechanically generated cavitation behavior of impact cracked specimens is obvious from SEM morphology, showing to the strong impact resistance of PP/EPDM blends. Increased EPDM content reduces the amount of scattered EPDM rubber particles by increasing the average diameter of dispersed particles, as seen by HRTEM images of the samples. The tensile and flexural properties of PP/EPDM blends were analysed. The rheological tests demonstrate that as the frequency increases, the complex viscosity drops, indicating that the melt is in a pseudoplastic condition. Due to the destruction of polymer chain mobility at greater cooling rates, DSC analysis indicates that percentage crystallinity values decrease as the cooling rate of crystallization increases, resulting in an incomplete crystallization process. The fact that PP/EPDM mixes have two glass transition temperatures indicates that they are immiscible. An investigation using the TGA found that the maximum degradation temperature (Tmax) of the PP/EPDM rubber mixtures may be sustained for long periods of time at very high operating temperatures. [ABSTRACT FROM AUTHOR]

Submicron‐sized wear particles are generally accepted as a potential cause of aseptic loosening when produced in sufficient volumes. With the accelerating use of increasingly wear‐resistant biomaterials, identifying such particles and evaluating their biological response is becoming more challenging. Highly sensitive wear particle isolation methods have been developed but these methods cannot isolate the complete spectrum of particle types present in individual tissue samples. Two established techniques were modified to create one novel method to isolate both high‐ and low‐density materials from periprosthetic tissue samples. Ten total hip replacement and eight total knee replacement tissue samples were processed. All particle types were characterized using high resolution scanning electron microscopy. UHMWPE and a range of high‐density materials were isolated from all tissue samples, including: polymethylmethacrylate, zirconium dioxide, titanium alloy, cobalt chromium alloy and stainless steel. This feasibility study demonstrates the coexistence of mixed particle types in periprosthetic tissues and provides researchers with high‐resolution images of clinically relevant wear particles that could be used as a reference for future in vitro biological response studies. [ABSTRACT FROM AUTHOR]

This study explains the synthesis of cobalt‐doped dysprosium oxide nanocubes (Co‐Dy2O3 NCs) and the modification of GCE (glassy carbon electrode), for the selective and sensitive detection of riboflavin (RF). The Co‐Dy2O3 NCs were synthesized by co‐precipitation method and characterized using spectroscopic and microscopic techniques like micro‐Raman Spectroscopy, X‐ray diffraction (XRD), X‐ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FT‐IR), High‐Resolution Transmission Electron Microscopy (HRTEM), Energy‐Dispersive X‐ray Spectroscopy (EDX), and High Resolution Scanning Electron Microscopy (HRSEM). The synthesized Co‐Dy2O3 NCs were coated on the glassy carbon electrode to detect and quantify the concentration of riboflavin in aqueous and real samples. The samples were analyzed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques with three‐electrode system. The modified electrode displays two linear concentration ranges (0.5–50, 50–300 μM) with a low detection limit (LOD) of 0.094 μM and high sensitivity of 3.67 μA μM−1 cm−2. Besides, the fabricated sensor has more selectivity, great reproducibility, repeatability and good stability. Finally, the Co‐Dy2O3 NCs modified GCE based sensor was effectively applied in real sample analysis using milk and egg yolk with good recovery. [ABSTRACT FROM AUTHOR]

Mechanical stirring of bulk Te in N‐methyl‐2‐pyrrolidone (NMP) solution at room temperature resulted in the formation of free‐standing few‐layer (∼1.2–2.8 nm) crystalline ultrathin nanosheets of tellurene with a large lateral thickness (∼1–1.6 μm) as confirmed by atomic force microscopy (AFM). High‐resolution transmission electron microscopy (HRTEM) confirms the presence of α‐ and β‐phases of tellurene. First‐principle density functional theoretical (DFT) based electronic structure calculations demonstrate the indirect band gap of bi‐layer β‐tellurene. The band gap decreases with increasing number of layers in the tellurene nanosheet. [ABSTRACT FROM AUTHOR]

We report the synthesis and electrocatalytic activity of poly(3‐hexylthiophene) stabilized nickel oxide nanoparticles (P3HT@NiO NPs). Employing semiconducting P3HT as a stabilizing agent produced well dispersed P3HT@NiO NPs with uniform size distribution (2.5 ± 1.2 nm). For comparison, NiO NPs stabilized with the small molecule 3‐hexylthiophene (3HT@NiO NPs) were also synthesized and characterized as reference material. The physiochemical properties of the developed hybrid P3HT@NiO were fully characterized using UV/Vis absorption spectroscopy, fluorescence spectroscopy, high resolution transmission electron microscopy (HRTEM) and X‐ray photoelectron spectroscopy (XPS). The electrocatalytic activities of the developed semiconducting polymer‐stabilized NPs were evaluated for the oxygen evolution reaction (OER) of water splitting. Our work reveals the electronic communication between P3HT and NiO NPs and demonstrates that P3HT@NiO NPs exhibit superior catalytic activity with an overpotential of 310 mV when compared to the reference 3HT@NiO NPs which exhibited an overpotential 560 mV. These results suggest that the heteroatom‐containing π‐conjugated semiconducting polymers can be employed as electrocatalytic performance enhancing and stabilizing ligands for the synthesis of ultrafine metal‐based NPs as efficient electrocatalytic platforms. [ABSTRACT FROM AUTHOR]

The current study focuses on the photocatalytic reduction of p‐nitrophenol using Europium, Yttrium and Lutetium doped Cerium oxide (CeO2) nanoparticles which were synthesized via chemical precipitation method. The synthesized nanoparticles were subjected to characterization using different analytical tools to confirm the formation of nanoparticles. They were characterized using X‐Ray diffraction (XRD) studies, Fourier Transform‐Infrared spectroscopy (FT‐IR), High resolution Scanning electron microscopy (HRSEM), High resolution Transmission electron microscopy (HRTEM), Energy dispersive X‐ray analysis (EDAX), X‐ray photoelectron spectroscopy (XPS), and UV‐Diffuse reflectance spectroscopy (UV‐DRS) studies. The synthesized rare earth nanomaterials were successfully applied for the photoreduction of the organic pollutant p‐nitrophenol with the addition of NaBH4 as reducing agent using 300 W Xenon lamp. The addition of the synthesized photocatalyst enhanced the reduction ability of NaBH4 in reducing p‐nitrophenol to p‐aminophenol. The results confirmed the superior photocatalytic activity of Lu0.05CeO2 compared to the other rare earth doped photocatalysts. The time taken by Lu0.05CeO2 photocatalyst for the complete reduction of p‐nitrophenol was 45 min and was found to be 96 % efficient in the reduction of 0.5 mM p‐nitrophenol to p‐aminophenol compared to the other photocatalysts. [ABSTRACT FROM AUTHOR]

Herein we report a facile approach for the preparation of a magnetically separable Fe3O4@poly(m‐phenylenediamine)@Cu2O nanocatalyst and its catalytic efficiency in the synthesis of 5‐phenyl‐[1,2,3]triazolo[1,5‐c]quinazolines from (E)‐1‐bromo‐2‐(2‐nitrovinyl)benzenes, aldehydes, and sodium azide under mild reaction condition is described. The morphology, chemical composition, interior structure and magnetic properties of the Fe3O4@PmPDs@Cu2O nanocomposites were studied using powder X‐ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray photoelectron microscopy, vibrating sample magnetometer and nitrogen adsorption‐desorption technique. The as‐prepared Fe3O4@PmPDs@Cu2O nanocatalyst was simply recovered using external magnet and reused up to successive six runs with no obvious loss in its catalytic efficiency and structural integrity (confirmed by powder X‐ray diffraction and transmission electron microscopy of recycled nanocatalyst) along with low leaching of copper (2.32 ppm) and iron (0.008 ppm) ions. The present protocol has a broad substrate scope with high yield in shorter reaction time and it does not require any additive or base. Overall, it has better green chemistry metrices like low E‐factor (0.93), process mass intensity (1.93), high reaction mass efficiency (51.9 %) and carbon efficiency (95 %). [ABSTRACT FROM AUTHOR]

In the present work, we have demonstrated the synthesis of Molybdenum Carbide‐reduced graphene oxide (Mo2C‐rGO) heterostructure. Uniquely, the in‐situ formation of rGO using D‐glucose in the heterostructure and its battery performance has been discussed. The High Resolution Transmission Electron Microscopy (HR‐TEM) study clearly shows the growth of Mo2C nanoparticles along with rGO confers a unique integrated layered heterostructure. X‐ray diffraction (XRD) and Raman study exhibits the formation of graphene oxide (GO) followed by multi‐layers of rGO along with hexagonal Mo2C. The electrochemical study of Mo2C‐rGO heterostructure demonstrates stable cycling performance and excellent rate capabilities. The heterostructure showed the initial capacity (1st discharge) around 632.23 mAh/g and specific capacity i. e., 537.91 mAh/g @ 0.5 A/g with 99–100 % columbic efficiency. The reversible capacities of 521.56 mAh/g, and 400.76 mAh/g were observed at current densities of 1 A/g and 2 A/g for 300 cycles, respectively, which justifies the stability of heterostructure. The cycled cell was investigated by using Electrochemical Imepedance Spectroscopy (EIS), ex‐situ XRD, and Field Emmision Scanning Electron microscopy (FESEM), which shows the negligible change in the ionic conductivity, structure, and morphology after 300 cycles. It shows the excellent stability of Mo2C‐rGO heterostructure. [ABSTRACT FROM AUTHOR]

Cobalt oxide hydrate (Co(OH)x) supported on metal oxides were prepared. The oxidative cleavage of C(OH)−C bond in alcohol was catalyzed by Co(OH)x/metal oxides using molecular oxygen as the oxidant, and the corresponding product was obtained with high selectivity. The composition and characteristics of the catalysts were analyzed by X‐ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), high‐angle ring dark‐field scanning TEM (HAADF‐STEM), N2 physico‐adsorption characterization, inductively coupled plasma optical emission spectrometry (ICP‐OES), Fourier transform infrared spectrum (FTIR), X‐ray photoelectron spectroscopy (XPS) and NH3‐temperature‐programmed desorption (NH3‐TPD). Additionally, a reasonable reaction mechanism was proposed based on the characterization results and a series of controlled experiments. Notably, this heterogeneous catalytic system did not require any additives and had good recycling performance. [ABSTRACT FROM AUTHOR]

The applications of self‐cleaning coatings on large scale are limited due to their poor durability, remnants of hazardous by‐products and lack of biocompatibility. We propose to solve this problem by developing TiO2‐ZrO2 composite‐based self cleaning coatings. In order to achieve this task another important aspect was to select biocompatible polymers poly (methyl methacrylate) and pluronic F‐127 (PF‐127) as they can enhance the self‐cleaning capability of TiO2‐ZrO2 which itself is biocompatible and endowed with anti‐bacterial capability. The selection of a preparation technique that could produce coatings mimicking the nature has also been important and hence Electrospraying technique was selected as the processing method. The samples were then characterized using various techniques like field emission scanning electron microscopy, X‐ray diffraction, high resolution transmission electron microscopy, Brunauer–Emmett–Teller analysis, and so forth to fathom the interlink between observed properties and morphology. High quality superhydrophobic and superhydrophilic films have been generated and the surfaces were modulated by the addition of tri‐block co‐polymer which was found to provide swapping of superhydrophobic nature to superhydrophilic nature. The integration of superhydrophobic, superhydrophilic, photocatalytic and antibacterial properties in the prepared microsphere coatings is a unique achievement and may interest those in the quest for self‐cleaning materials for antibacterial coatings in mitigating surgical site infections, medical implants, coronary stent surfaces, and so forth. [ABSTRACT FROM AUTHOR]

In this paper, sulfonic acid functionalize magnetic starch (denoted Starch/SPION@SO3H) is fabricated by the polymerization of 4‐styrenesulfonic acid on the surface of magnetic starch. Magnetic starch (Starch/SPION) is synthesized by covalent modification of starch by silica capsulate superparamagnetic iron oxide nanoparticles (SPION). For this purpose, Starch/SPION is modified by allyltrimethoxysilane, follows by the polymerization of 4‐styrenesulfonic acid onto this material. The catalyst is characterized by various characterization techniques, including transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA), vibrating‐sample magnetometer (VSM), X‐ray photoelectron spectroscopy (XPS), and acid/base titration. The characterizations prove the structure of Starch/SPION@SO3H catalyst. The catalytic activity of Starch/SPION@SO3H is evaluated in the multicomponent reaction of 4‐hydroxycoumarin, benzaldehydes, dimedone, and ammonium acetate for the synthesis of chromeno[4,3‐b]quinoline‐6,8(9H)‐dione derivatives. The catalyst shows very good activity in the synthesis of chromeno[4,3‐b]quinoline‐6,8(9H)‐dione derivatives. Several benzaldehydes with electron donating or electron withdrawing functionalities are used as starting material and all the substrates give the desired products in high isolated yields. In addition, the catalyst is extremely reusable during 10 sequential runs. Characterization of Starch/SPION@SO3H catalyst by TEM, VSM, and acid/base titration after recovery from the reaction proves the stability of the catalyst in the reaction conditions. [ABSTRACT FROM AUTHOR]

Interest in layered Ruddlesden–Popper (RP) strongly correlated manganites of Pr0.5Ca1.5MnO4 as well as in their thin film polymorphs is motivated by the high temperature of charge orbital ordering above room temperature. The c‐axis orientation in epitaxial films is tailored by different SrTiO3 (STO) substrate orientations and CaMnO3 (CMO) buffer layers. Films on STO(110) show in‐plane alignment of the c‐axis parallel to the [100] direction. On STO(100), two possible directions of the in‐plane c‐axis lead to a mosaic like, quasi 2D nanostructure, consisting of RP, rock‐salt, and perovskite blocks. With the CMO buffer layer, Pr0.5Ca1.5MnO4 epitaxial films with c‐axis out‐of‐plane are realized. Different physical vapor deposition techniques as ion beam sputtering, pulsed laser deposition and metalorganic aerosol deposition are applied in order to distinguish effects of growth conditions from intrinsic epitaxial properties. Despite their very different growth conditions, surface morphology, crystal structure, and orientation of the thin films reveal a high level of similarity as verified by X‐ray diffraction, scanning, and high resolution transmission electron microscopy. For different epitaxial relations stress in the films is relaxed by means of modified interface chemistry. The charge ordering in the films occurs at a temperature close to that expected in bulk material. [ABSTRACT FROM AUTHOR]

p‐Nitrophenol (p−NP) is a high priority toxic pollutant and that has harmful effects on human, animals and plants. Thus, the detection and determination of p−NP present in the environment is an urgent as well as highly important requisite. The present article, therefore focused on the construction of a novel electrochemical sensor based on NiO nanoparticles/α‐cyclodextrin functionalized reduced graphene oxide modified glassy carbon electrode (NiO−NPs‐α‐CD‐rGO‐GCE) for the selective and sensitive detection of p−NP. UV‐vis, high resolution transmission electron microscopy (HR‐TEM), selected area electron diffraction pattern (SAED) and X‐ray diffraction (XRD) analysis confirms the formation of highly pure NiO nanoparticles. Field emission scanning electron microscopy (FE‐SEM), energy dispersive X‐ray spectroscopy (EDS), and cyclic voltammetry (CV) were used to characterize the step‐wise electrode modification process. DPV was carried out to quantify p−NP within the concentration range of 1−10 μM and found the detection limit of 0.12 nM on the basis of the signal‐to‐noise ratio S/N=3. The electrode can able to detect different isomers of nitrophenols. Interferences of other pollutants such as phenol, p‐aminophenol, o‐ and m‐ nitrophenol, 4‐chlorophenol, 2,6‐dichlorophenol and ions like K+, Cd2+, Cl−, SO42− did not affect the sensing of p−NP. The newly developed sensor exhibited diffusion controlled kinetics and had excellent sensitivity, selectivity and reproducibility for the detection of p−NP. The electrode showed good recoveries in real sample analysis. [ABSTRACT FROM AUTHOR]

Cuboid‐shaped anatase TiO2 nanocrystals with co‐exposed {101} and [111]‐facets (or {101} and {100} facets), diamond‐shaped, rod‐like and irregular anatase TiO2 nanocrystals with dominant {010} facets were controllably synthesized from titanium (IV) ethoxide (TEOT) using HF as a capping agent via a facile sol‐gel procedure, and characterized by X‐ray powderdiffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), nitrogen adsorption, photoluminescence (PL) spectra, UV‐vis diffuse reflectance spectra,and electrochemical impedance spectroscopy (EIS). For the as‐prepared anatase TiO2 nanocrystals, the 0.5HF‐TiO2 revealed the best photocatalytic efficiency under UV light irradiation: 94.1 % of methylene blue (MB) was photodegraded within 90 min. The reaction rate constant k(min−1) was 1.39, 1.47, 1.59, 1.66, 1.92, 2.75, and 30.5 times higher than that of 2.0HF‐TiO2 (2.20×10−2 min−1), 1.5HF‐TiO2 (2.07×10−2 min−1), 1.0HF‐TiO2 (1.92×10−2 min−1), 2.5HF‐TiO2 (1.84×10−2 min−1), 3.0HF‐TiO2 (1.59×10−2 min−1), Bodi‐TiO2 (1.11×10−2 min−1), and the blank sample (0.10×10−2 min−1), respectively. Compared to other as‐prepared anatase TiO2 nanocrystals with the similar co‐exposed crystal facets, the highest efficiency of 0.5HF‐TiO2 could be attributed to the minimum crystal size,narrower pore size distribution, the maximum specific surface area, the lowest PL intensity and charge‐transfer resistance, andthe smallestrecombination resistance. [ABSTRACT FROM AUTHOR]

In a sample with nominal composition BiCr2S5 a new misfit layer compound has been synthesized and studied via transmission electron microscopy (TEM). It presents a composite modulated structure with a composition that can be formulated as (BiS)1.19[(CrS2)‐Bi1/3‐(CrS2)]. It consists of the periodic stacking of a Q layer (BiS) with two H layers (CrS2), ...QHHQHH..., with additional bismuth atoms inserted between the H layers. Selected area electron diffraction (SAED) patterns show an almost commensurate fit between the pseudo‐tetragonal Q (BiS) and the pseudo‐orthohexagonal H (Bi1/3Cr2S4) subcells along the misfit direction a, being b the same for both sublattices and c the layers stacking direction. In addition to the characteristic misfit modulation between the two sub‐structures, a second modulation is observed in the H sub‐structure produced by the ordering of bismuth atoms within the Van der Waals gap that occurs between consecutive H layers. High resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) images show ordered stacking sequences between the (BiS) and (Bi1/3Cr2S4) layers. Besides, disordered intergrowths have been occasionally found as well as different kinds of twinning defects. [ABSTRACT FROM AUTHOR]

The electromagnetic Interference (EMI) shielding effectiveness of W‐Type barium hexaferrite (BaCo2Fe16O27) and reduced graphene oxide (RGO) nanofillers reinforced poly(vinylidenefluoride) (PVDF) polymer composite films are reported. Two different amounts of BaCo2Fe16O27 (10 wt% and 30 wt%) nanofillers and fixed amount of RGO (10 wt%) are loaded in PVDF matrix by solvent casting in order to fabricate the multifunctional PVDF/RGO/BaCo2Fe16O27 composite films. The synthesized samples are investigated using various instruments including X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), Raman spectroscopy, high resolution scanning electron microscopy (HRSEM), energy dispersive X‐ray spectroscopy (EDX), X‐ray photoelectron spectroscopy (XPS) and vibrating sample magnetometer (VSM) analysis. The microwave properties of PVDF/RGO/BaCo2Fe16O27 composites are tested with vector network analyser (VNA) in 8–12 GHz frequency (X‐Band). The possible mechanism of EMI shielding is investigated from the analysis of complex permittivity and permeability.The resultant flexible films exhibit desirable EMI SE of 35.94 dB at 11.8 GHz for the 10 wt% of BaCo2Fe16O27 addition in PVDF composite for a very small thickness of 0.2 mm. The combination of high dielectric loss (tanδε= 1.63) and magnetic loss (tanδμ= 0.26) contributes to high absorption of 29.85 dB (>99% attenuation) dominated over reflection. Thus, the simple and cost‐effective fabrication of ultrathin and flexible PVDF/RGO/BaCo2Fe16O27 composite film with low filler content has a great potential as suppresser in electromagnetic fields. [ABSTRACT FROM AUTHOR]

Silica‐bonded porous SiC ceramics were fabricated using nano‐β‐SiC powder‐carbon black template compacts by sintering in air at 600°C‐1200°C. The intrinsic microstructures of the porous ceramics were characterized by high‐resolution transmission electron microscopy, which led to the following observations: (a) a core (SiC)‐shell (SiO2) structure was formed, owing to the partial oxidation of nano‐SiC particles during sintering; (b) a low‐temperature (800°C) β‐to‐α polytypic phase transformation was observed, owing to the oxidation‐induced residual thermal stresses; and (c) non‐graphitic carbons were precipitated inside the SiC core, owing to the segregation of C atoms emitted at the strained SiC‐SiO2 interface. [ABSTRACT FROM AUTHOR]

We analyzed the surface atomic structure of highly oriented pyrolytic graphite (HOPG) substrate exfoliated with adhesive tape, using high‐resolution transmission electron microscopy and scanning transmission electron microscopy‐electron energy‐loss spectroscopy (STEM‐EELS). The surface step height of the exfoliated HOPG substrate was determined using high‐angle annular dark‐field‐scanning transmission electron microscopy (HAADF‐STEM) images and the depth profiles of the EELS spectra of a cross‐sectioned thin foil specimen prepared via focused ion beam milling. The exfoliated surface of the HOPG substrate presented disordered and curved graphene layers. The STEM‐EELS measurements indicated that upon exfoliation, the surface of the HOPG substrate reacted with atmospheric water and oxygen molecules. [ABSTRACT FROM AUTHOR]

Resistive switching in oxide‐based structures is intensively studied for the development of ultra‐fast non‐volatile memories with low consumption and neuromorphic electronic devices. Here, evidence of interface‐controlled, reversible, bi‐polar resistance switch in prototype multiferroic BaTiO3/La0.75Sr0.25MnO3 (BTO/LSMO) system is given. The analysis of current–voltage hysteresis curves of a thick Au/BTO/LSMO structure reveals the existence of a 2.55 nm‐thick barrier layer at the bottom BTO/LSMO interface, leading to a tunnel electroresistance of ≈1700%. In the native state where BTO polarization points downward, high resolution electron microscopy and electron energy loss spectroscopy show Ba/(La,Sr) and Ti/Mn cationic intermixing, together with a valency reduction of Mn cations and an oxygen deficiency at the interface. This results in a high resistance state, due to partial loss of the metallicity and of the double exchange magnetic interaction in the oxygen‐deficient LSMO. The switch to the low resistance state, achieved by upward electric field, is explained in terms of re‐oxydation of Mn cations at the interface (decrease of the Mn3+/Mn4+ ratio), with oxygen vacancies migration from LSMO to BTO. This work emphasizes the crucial role of ionic exchanges and of redox processes at interfaces, both on ferroelectric bound charge screening and on resistive switching. [ABSTRACT FROM AUTHOR]

In this work, graphene nanoplatelets have been synthesized using liquid phase exfoliation of graphite flake powder. The exfoliated graphene nanoplatelets were identified and characterized by using UV–Visible–NIR spectroscopy, High resolution transmission electron microscopy, electron diffraction, scanning electron microscopy and X‐ray diffraction. The obtained graphene nanoplatelets and nano alumina at various weight ratios were dispersed in an epoxy matrix to enhance the surface roughness (Ra), micro hardness (Hv) and coefficient of friction (CoF) of epoxy hybrid nanocomposites. The results showed that the Ra and CoF value for the combined loading of 0.2 wt% of graphene nanoplatelets and 0.8 wt% of alumina into the epoxy was decreased to 41.02 and 20.01% whereas, the Hv value was increased to 10.04% when compared with the neat epoxy. The improved mechanical and tribological behaviors are suitable for the applications bearing and coating. [ABSTRACT FROM AUTHOR]

Sol‐gel and hand milling techniques were used to prepare a lithium iron phosphate‐lithium manganese silicate (LiFePO4−Li2MnSiO4) hybrid cathode materials. The structural studies from x‐ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) show that the materials are well crystallized although few impurities were observed in the pristine LiFePO4 (LFP) and Li2MnSiO4 (LMS) materials. We used graphene to coat the hybrid cathode materials in order to increase its conductivity and enhance the electrochemical performance. The successful reduction of the graphene oxide into graphene nanosheets was confirmed with the results from the Fourier transform infrared (FTIR) and Raman spectroscopy. The morphological analysis indicate that the pristine materials are made of spherical nanoparticles that are slightly agglomerated while the sol‐gel‐prepared hybrid cathode materials show evenly distributed spherical nanoparticles with minimal agglomeration. The in situ sol‐gel technique gave more homogenously mixed material in comparison to the hand milling method and particle sizes of 37 and 23 nm respectively were obtained for the plain, and graphenised sol gel derived hybrid materials. The sol‐gel derived hybrid materials are also the most thermally stable giving a total weight loss of 4.5 % and 3.4 % for the plain and graphenised cathodes respectively. While the LFP‐LMS hybrid cathode materials performed better electrochemically more than the pristine materials in terms of enhanced current and specific capacities, the graphenised LFP‐LMS hybrid cathode materials showed better electrochemical properties compared to those without graphene. This is associated with the presence of graphene nanosheets in these samples. All the results confirmed that the graphenised LiFePO4−Li2MnSiO4 hybrid cathode material prepared via in situ sol‐gel method performed better than those of the hand milling method. [ABSTRACT FROM AUTHOR]

A green nano‐sized ceramic pigment Co0.6Zn0.4Al0.8Cr1.2‐xSmxO4 has been successfully prepared by doping ions Zn2+, Cr3+, and Sm3+ into the crystalline CoAl2O4 spinel and using the complex‐gel method along with agar as complexing and combustion agent. The Infrared Spectroscopy, X‐ray diffraction, Thermo‐gravimeter, High resolution transmission electron microscopy, Automatic color reader, and UV Vis diffuse reflectance were applied to characterize the pigment power and its gel precursor. The results reveal that the introduction of Zn2+, Cr3+, and Sm3+ could change the occupation status of ions in the tetrahedral and octahedral framework of CoAl2O4 spinel, leading to the colorant variation of the blue cobalt pigment CoAl2O4, With increasing the content of Sm3+ ion, the reflection peak position of the pigments in visible spectrum appeared a red‐shift, ie the color transition from blue green to yellow green, and the average reflectivity in the violet region decreased to 13.31%, and the band gap energy also changed from 3.47 to 3.20 eV. This illustrates the better UV absorption of this green pigment and can be used as UV shielding material. With the hydrochloric acid or sodium hydroxide solution treatment, this pigment was found to be durable in chemical stability. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (NPs) in a transparent dielectric matrix represent a very intriguing system due to the plasmonic absorption tunable in the range of visible wavelengths. Herein, the preparation and physical characterization of plasmonic titania–silver dots thin films are reported. The synthesis parameter that leads to making a TiO2 matrix in which the Ag NPs are actually incorporated is carefully analyzed and controlled. Morphological (scanning electron microscopy, transmission electron microscopy, high resolution electron microscopy), structural (selected area diffraction, X‐ray diffraction), and spectroscopic (Raman spectroscopy) characterization techniques attest that the Ag NPs are spherical and homogeneously distributed into the TiO2 dielectric matrix in the structural modification of anatase. The study of the optical properties of films concludes the work. Plasmonic resonance is analyzed according to the light scattering theory. [ABSTRACT FROM AUTHOR]

Summary: This paper takes a fundamental view of the electron energy loss spectra of monolayer and few layer MoS2. The dielectric function of monolayer MoS2 is compared to the experimental spectra to give clear criteria for the nature of different signals. Kramers–Krönig analysis allows a direct extraction of the dielectric function from the experimental data. However this analysis is sensitive to slight changes in the normalisation step of the data pretreatment. Density functional theory provides simulations of the dielectric function for comparison and validation of experimental findings. Simulated and experimental spectra are compared to isolate the π and π + σ surface plasmon modes in monolayer MoS2. Single‐particle excitations obscure the plasmons in the monolayer spectrum and momentum resolved measurements give indication of indirect interband transitions that are excited due to the large convergence and collection angles used in the experiment. Lay Description: Two‐dimensional materials offer a path forward for smaller and more efficient devices. Their optical and electronic properties give way to beat the limits set in place by Moore's Law. Plasmon are the collective oscillations of electrons and can confine light to dimensions much smaller than its wavelength. In this work we explore the plasmonic properties of MoS2, a representational candidate from a family of 2D materials known as transition metal dichalcogenides. High resolution electron microscopy and spectroscopy provide insights in the plasmonic properties of MoS2 down to an atomic scale. Experimental results show the relationship between plasmons and interband transitions in the electron energy loss spectrum. Density functional theory provides a theoretical support for the experimental findings and provides commentary on the fundamental underlying physics. [ABSTRACT FROM AUTHOR]

The active sites of Cu/ZnO‐based catalysts, commercially applied for the hydrogenation of CO2 or CO2‐rich synthesis gas, are still subject of current debates. Generally, the discussion is focused on the nature of the interfacial contact between Cu and ZnO, particularly whether it is rather of oxidic (Cu−ZnO) or alloying (Cu−Zn) character. We report on kinetic investigations on a Cu/ZnO : Al high performance catalyst activated at different temperatures. Incrementally increasing temperature under reductive conditions leads also to increased CuZn‐alloy formation, analyzed by in‐situ X‐ray diffraction, in‐situ X‐ray absorption spectroscopy and high resolution transmission electron microscopy. The combination of the catalytic data and the complementary characterization techniques provide valuable insights on the relevant reaction sites for CH3OH formation. Our results highlight the complexity of the interfacial contact with evidence for Cu−ZnO reaction sites and clarify the negative impact of CuZn alloy formation on the nature of the active site. [ABSTRACT FROM AUTHOR]

Summary: Regeneration of diesel particulate filter (DPF) is a complicated process due to its high operating temperature and associated oxidation of soot on the filter substrate. Several oxidation mechanisms of diesel soot have been proposed based on reaction kinetics, but more information about the oxidation phenomena is needed in a practical system, that is, soot oxidation on a DPF substrate. In this work, the DPF regeneration process was, for the first time, visualized at the particle scale ex‐situ, in time‐lapse series, using field emission scanning electron microscopy (FE‐SEM). Time‐lapse transformation of soot cake layer on a real DPF was followed from initiation through the complete regeneration process. In parallel, transformation of the soot primary particle diameter was directly measured using high‐resolution transmission electron microscopy. FE‐SEM visualization clearly showed shrinkage of the soot cake layer on the DPF wall as oxidation progressed. Furthermore, diameter distribution analysis revealed a trend of shrinkage of the nanoscale soot primary particles during oxidation, supporting the FE‐SEM observations of the micron‐scale shrinkage of the agglomerated soot cake layer. Fragmentation of the shrunken soot cake layer was also observed and is suspected to be a result of locally higher gas flow that depends on surface pore morphology of the filter substrate. Lay Description: In this work, the DPF regeneration process was, for the first time, visualized at the particle scale ex‐situ, in time‐lapse series, using field emission scanning electron microscopy (FE‐SEM). Time‐lapse transformation of soot cake layer on a real DPF was followed from initiation through the complete regeneration process. In parallel, transformation of the soot primary particle diameter was directly measured using high resolution transmission electron microscopy. FE‐SEM visualization clearly showed shrinkage of the soot cake layer on the DPF wall as oxidation progressed. Furthermore, diameter distribution analysis revealed a trend of shrinkage of the nano‐scaled soot primary particles during oxidation, supporting the FE‐SEM observations of the shrinkage of the micron‐scale agglomerated soot cake layer. Fragmentation of the shrunken soot cake layer was also observed and is suspected to be a result of locally higher gas flow that depends on surface pore morphology of the filter substrate. Further detail mechanism about transformations of the soot cake layer was additionally discussed based on electrostatic attraction. [ABSTRACT FROM AUTHOR]

In this work, dehydrogenation of NaBH4 in alkaline solutions was catalyzed by amorphous Co‐B catalysts supported on nitrogen doped carbon (N‐C) that is rarely utilized in this field. The physicochemical properties of the as‐prepared catalysts were characterized by X‐ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscopy (HRTEM), X‐ray Photoelectron Spectroscopy (XPS), Raman Spectroscopy and BET (Brunner−Emmet−Teller) measurements. Among all the catalysts made in this paper, Co‐B/N‐C‐700 exhibited best activity, which is likely to be attributed to the possession of more metal Co as active sites. The hydrogen generation rate (HGR) reached 2649 ml H2 min−1 g−1cat in 10 wt. % NaOH + 10 wt. % NaBH4 solution at 30 °C. The value of activation energy is 37.57 kJ mol−1 and compares favorably with values of some previous reports. Besides, influences of NaOH concentration, NaBH4 concentration, temperature, recycle times and amount of catalyst for the catalytic performance of Co‐B/N‐C‐700 were also investigated to reflect more on hydrolysis of sodium borohydride. [ABSTRACT FROM AUTHOR]

Heterostructures of strongly correlated oxides demonstrate various intriguing and potentially useful interfacial phenomena. LaMnO3/SrMnO3 superlattices are presented showcasing a new high‐temperature ferromagnetic phase with Curie temperature, TC ≈360 K, caused by electron transfer from the surface of the LaMnO3 donor layer into the neighboring SrMnO3 acceptor layer. As a result, the SrMnO3 (top)/LaMnO3 (bottom) interface shows an enhancement of the magnetization as depth‐profiled by polarized neutron reflectometry. The length scale of charge transfer, λTF ≈2 unit cells, is obtained from in situ growth monitoring by optical ellipsometry, supported by optical simulations, and further confirmed by high resolution electron microscopy and spectroscopy. A model of the inhomogeneous distribution of electron density in LaMnO3/SrMnO3 layers along the growth direction is concluded to account for a complex interplay between ferromagnetic and antiferromagnetic layers in superlattices. [ABSTRACT FROM AUTHOR]

The LiRh‐type crystal structure of the equiatomic intermetallic compound IrZn turns out to be a competitor to the otherwise energetically favored CsCl‐type structures of congeneric transition metal zinc phases, thus enlightening the structural impact of element‐specific factors beyond the Hume‐Rothery concept. [ABSTRACT FROM AUTHOR]