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The prepared NVOY electrode achieves high stability and excellent cycle performance for AZIBs by embedding polypyrrole in ammonium vanadate layers to remove excess ammonium ions, expand the interlayer spacing, and enhance electronic conductivity. [Display omitted] Ammonium vanadate with stable bi-layered structure and superior mass-specific capacity have emerged as competitive cathode materials for aqueous rechargeable zinc-ion batteries (AZIBs). Nevertheless, fragile N H...O bonds and too strong electrostatic interaction by virtue of excessive NH 4 + will lead to sluggish Zn2+ ion mobility, further largely affects the electro-chemical performance of ammonium vanadate in AZIBs. The present work incorporates polypyrrole (PPy) to partially replace NH 4 + in NH 4 V 4 O 10 (NVO), resulting in the significantly enlarged interlayers (from 10.1 to 11.9 Å), remarkable electronic conductivity, increased oxygen vacancies and reinforced layered structure. The partial removal of NH 4 + will alleviate the irreversible deammoniation to protect the laminate structures from collapse during ion insertion/extraction. The expanded interlayer spacing and the increased oxygen vacancies by the virtue of the introduction of polypyrrole improve the ionic diffusion, enabling exceptional rate performance of NH 4 V 4 O 10. As expected, the resulting polypyrrole intercalated ammonium vanadate (NVOY) presents a superior discharge capacity of 431.9 mAh g−1 at 0.5 A g−1 and remarkable cycling stability of 219.1 mAh g−1 at 20 A g−1 with 78 % capacity retention after 1500 cycles. The in-situ electrochemical impedance spectroscopy (EIS), in-situ X-ray diffraction (XRD), ex-situ X-ray photoelectron spectroscopy (XPS) and ex-situ high resolution transmission electron microscopy (HR-TEM) analysis investigate a highly reversible intercalation Zn-storage mechanism, and the enhanced the redox kinetics are related to the combined effect of interlayer regulation, high electronic conductivity and oxygen defect engineering by partial substitution NH 4 + of PPy incorporation. [ABSTRACT FROM AUTHOR]

Building up and an investigating the efficiency of the cost-effective modified graphite for hybrid supercapacitor application is fascinating due to an extraordinary performance of graphite in battery application in day-to-day life about past decades. The metal oxides (Fe, Co, Ni) embedded in graphite was synthesized through the facile ultrasonication-assisted technique. Fe–Co–Ni deposited on graphite (Fe–Co–Ni-G) was studied structurally and morphologically by fourier transform infrared spectroscopy, X-ray diffraction analysis, field emission scanning electron microscopy, and high resolution transmission electron microscopy analyses. The electrochemical studies such as cyclic voltammetry, Galvanostatic charge–discharge analysis, and electrochemical impedance spectroscopy (EIS) analysis were revealed the supercapacitor performance of Fe–Co–Ni-G composite. The superior calculated areal capacitance of Fe–Co–Ni-G was 1355 mF cm−2 at 2 mA cm−2 which was higher than single metal deposited graphite (Fe-G 490 mF cm−2 at 2 mA cm−2) composite. EIS study supported the higher diffusion process of Fe–Co–Ni-G directed to higher supercapacitor performance that is possible for day-to-day life applications. [ABSTRACT FROM AUTHOR]

NiMoS/TiMg and NiWS/TiMg nanocatalysts were synthesized, characterized by various techniques and tested in the hydrodesulphurization (HDS) of dibenzothiophene (DBT). TiMg mixed oxides containing 5, 10 or 15 wt% of MgO were prepared by sol–gel and then used as catalyst supports. A constant atomic ratio of Ni/(Ni + M) = 0.5 was kept for all the catalysts (M = Mo or W). The catalysts were first prepared by sequential-wet impregnation. Then, after an ex-situ sulfidation process, they were characterized by high resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), and physisorption of N2 following the BET method. The presence of MgO in the NiMoS/TiMg and NiWS/TiMg catalysts resulted in an enhancement in the HDS activity of DBT. In addition, their HDS activities were higher than those observed in the NiMoS/Ti and NiWS/Ti catalysts. Furthermore, higher HDS activity was found for the NiMoS/TiMg compared with their NiWS/TiMg catalysts counterpart. [ABSTRACT FROM AUTHOR]

In this study, mixed phase (tetragonal and monoclinic) Zirconia nanoparticles (ZrO2 NPs) namely, ZS3, ZS7 and ZS10 were synthesized via hydrothermal method at different pH values of (3, 7, 10) respectively. A combination of Powder X-ray diffraction (PXRD), High Resolution Transmission Electron Microscopy (HRTEM), and Selected Area Electron Diffraction (SAED) characterization techniques confirmed the formation of mixed phase ZrO2 nanoparticles. The photocatalytic behavior of synthesized ZrO2 NPs was examined for the degradation of anionic Congo Red (CR) Dye under visible light irradiation. A systematic study of the efficiency of the prepared ZS3, ZS7 and ZS10 nanoparticles was compared and it was found that ZS7 outperformed the ZS3 and ZS10 materials, having removal efficiency of up to 98.9% with 0.1 g of the prepared ZS7 nanoparticles for 75 ppm of Congo Red (CR) dye. Furthermore, the surface area analysis revealed that among the prepared materials, ZS7 exhibited the highest surface area, thereby corroborating the finding of its superior catalytic efficiency. Under the optimized experimental conditions, the degradation of dye followed first-order kinetics. ZS7 showed the highest removal efficiency in just 60 min of contact time for all the CR dye concentrations ranging from 50 to 100 ppm, making it a superior catalyst for the efficient removal of the targeted Congo Red dye. [ABSTRACT FROM AUTHOR]

Currently, surface reflection of incident sunrays over solar cells results in degradation of output performance of the solar cells. This can be sorted out using an antireflection coating. In this investigation, ARC materials such as Titanium dioxide (TiO 2), Aluminium oxide (Al 2 O 3) and blended TiO 2 – Al 2 O 3 were utilized over the mono-crystalline Si (m-Si) solar cells. The ARCs for m-Si solar cell was coated using RF sputtering method. The optical, structural, electrical, I–V characteristics and temperature behavior of solar cell samples with coating and bare cells were studied. The elemental analysis was carried out using X-ray diffraction (XRD) method. The morphological study was conducted using High Resolution Transmission Electron Microscopy (HR-TEM) and Atomic Force Microscope (AFM). The electrical resistivity was measured in dark at room temperature using four-point probe technique. Optical characteristics was determined using UV–visible spectroscopy. It was discovered that the TiO 2 – Al 2 O 3 blend coated cell (I3) shows great performance than the other coatings. I3 solar cell demonstrated high power conversion efficiency (PCE) of 19.42 % and 20.16 %, when exposed to direct sunlight and neodymium radiation in both open and controlled environments. The findings indicate that TiO 2 – Al 2 O 3 blends are a suitable material for ARC applications, since they effectively reduce the incident photons scattering. [ABSTRACT FROM AUTHOR]

Rare earth complexes have gained attention in recent years for their remarkable luminescence properties, especially their long lifetimes, clear emission bands, and significant luminous quantum efficiency. In the ultraviolet area, the lanthanide ions exhibit relatively tiny absorption. The current investigation systematically portrays the tailoring of the micro-structural, opto-electonic and defect related features of the sol-gel derived pristine and rare earth element-samarium (Sm3+) substituted tin oxide (SnO 2) i.e., Sn 1- x Sm x O 2 (x = 0.0, 0.1, 0.2 & 0.3) nanoparticles (NPs). The structural, optical, electronic, morphological, photo-induced luminescence and defects related characteristics of the NPs were explored as a function of samarium (Sm3+) substitution level. In-depth analysis of the structure-property correlation of the Sn 1- x Sm x O 2 NPs is the goal of this study, focusing especially on the properties related to vacancy evolution and luminescence. The elemental mapping results revealed through energy dispersive X-ray spectroscopic (EDS) technique confirmed that the Sm-substitution is distributed uniformly throughout the NPs. The X-ray powder diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and field emission scanning electron microscopy (FESEM) studies corroborate that the Sm3+ substitution in the SnO 2 matrix causes the decrease in crystallite size of the NPs and increase in the dislocation density. A monotonic increase in lattice strain has been observed using the Williamson – Hall (W – H) approach, which is in line with the NPs' increased dislocation density and decreased crystallite size with the Sm3+ substitution level. The presence of vacancy-type defects inside the NPs was demonstrated by positron annihilation lifetime (PAL) spectroscopic measurements, and a decrease in defects was noticed as the level of Sm3+ substitution increased. To explore the optical characteristics and the evolution of the energy band gap with Sm3+ substitution level, the optical absorption (OA) spectroscopic measurement was carried out. As the Sm-substitution level rises, the optical energy band gap of the substituted SnO 2 NPs widens relative to that of pure SnO 2 NPs. The existence of various absorbance bands corresponding to the atomic vibrations within the NPs were investigated by the Fourier-transform infrared (FT-IR) spectroscopic technique. The photo-induced fluorescence (FL) emission spectroscopic analysis evidenced that the defect density decreased as the Sm-substitution level increased, which is in accordance with the PAL spectroscopic studies. The FL spectra showed the two typical near band edge (NBE) and deep level emission (DLE) peaks of the NPs. The proportion of different defects and vacancies associated with the FL emission transitions are portrayed as Pie-chart diagrams. The tailored NPs can establish to be effective candidates for possible spintronic and optoelectronic applications including magneto-optical devices. [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]

Superconducting qubits have arisen as a leading technology platform for quantum computing, which is on the verge of revolutionizing the world's calculation capacities. Nonetheless, the fabrication of computationally reliable qubit circuits requires increasing the quantum coherence lifetimes, which are predominantly limited by the dissipations of two-level system defects present in the thin superconducting film and the adjacent dielectric regions. In this paper, we demonstrate the reduction of two-level system losses in three-dimensional superconducting radio frequency niobium resonators by atomic layer deposition of a 10 nm aluminum oxide Al2O3 thin films, followed by a high vacuum heat treatment at 650 °C for few hours. By probing the effect of several heat treatments on Al2O3-coated niobium samples by x-ray photoelectron spectroscopy plus scanning and conventional high resolution transmission electron microscopy coupled with electron energy loss spectroscopy and energy dispersive spectroscopy, we witness a dissolution of niobium native oxides and the modification of the Al2O3-Nb interface, which correlates with the enhancement of the quality factor at low fields of two 1.3 GHz niobium cavities coated with 10 nm of Al2O3. [ABSTRACT FROM AUTHOR]

The synthesis of undoped and copper doped ZnS nanoparticles (NPs) by a facile starch mediated microwave assisted hydrothermal route is reported in this work. Polycrystalline, cubic ZnS nanostructure of the samples were revealed by X-ray diffraction studies. High resolution transmission electron microscopy (HRTEM) analysis revealed the crystalline nature of NPs with size distribution in 2–7 nm range. Analysis of X-ray emission induced by particles of samples indicated presence of copper content in the sample. Cu doping showed a strong influence on the green emission properties of the ZnS NPs under UV light illumination. The band gap values determined from UV–Vis absorption studies were higher than that for bulk ZnS (3.68 eV), confirming quantum confinement effect. Further, starch capping and Cu doping confirmed by Fourier transform infra-red (FTIR) spectra. A strong PL emission around 507 nm observed due to carrier transition from conduction band of ZnS to Cu2+ t 2 level. The intensity of this peak reduced at high dopant concentration due to quenching. [ABSTRACT FROM AUTHOR]

This paper reports synthesis by wet chemical route for neodymium doped lanthanum arsenates nanoparticles with chemical formula NdxLa1−xAsO4 (x = 0.0, 0.05, 0.10 and 0.15) and its characterization. Powder X-ray diffraction (PXRD) confirms monoclinic structure of the prepared nanomaterials. Crystallite size decreases with increasing concentration of Nd3+ ions. PXRD results are further validated by Rietveld refinement with low values of goodness factor (χ2). Morphology has been investigated by high resolution transmission electron microscopy (HRTEM) equipped with selected area electron diffraction (SAED) which shows the crystalline nature of nanomaterials. Various functional groups present have been studied by FTIR spectroscopy. The optical band gap calculated using UV–Vis diffuse reflectance spectroscopy is found to decrease with increasing dopant concentration. The emission spectrum studied by applying photoluminescence (PL) spectroscopy. At 315 nm excitation, the NdxLa1−xAsO4 exhibits a bright red emission with emission peaks in the range of 610–630 nm. Chromaticity plot shows that chromaticity coordinates are located in the red region. The dielectric analysis carried out to study variation of dielectric constant with frequency over range of 1–25 kHz and temperature range of 20–200 °C. The conductivity measurements are carried out and activation energy has been calculated. The variation of electrical modulus with frequency has also been observed. [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]

Nano size Z n 2 − x C u x V 2 O 7 (x = 0 ∼ 2) ceramics, prepared through a single step modified combustion method has been sintered at a relatively lower temperature for the first time. The thermodynamics of phase transition of the as prepared samples with respect to temperature was studied using Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). The powder X-ray diffraction (XRD) analysis of the samples along with Rietveld refinement of the data confirmed that the compositions crystalized in monoclinic structure despite increasing x from 0 to 2. Raman spectroscopic analysis carried out in the powders also corroborated the XRD analysis. The High Resolution Transmission Electron Microscopy (HRTEM), shows that the annealed powders have a particle size of around 43 nm. A systematic study on the densification behaviour of the cylindrical pellets was conducted in the range 680 0 C - 780 0 C to obtain optimal density. The microstructural study of the pellets sintered to the optimum density was conducted using Scanning Electron Microscopy (SEM). The electrical properties of the polished samples were measured using an Impedance Analyzer in the range 100 Hz – 1 MHz at different temperatures from 50 °C to 500 °C. On varying x from 0 to 2, the dielectric constant of Zn 2 V 2 O 7 ceramic showed a gradual increase from 7.9 to 15.9 at 10 kHz at room temperature. The Zn 2 V 2 O 7 ceramics showed a conductivity range from 4.10 × 10 − 9 S cm − 1 to 4.56 × 10 − 7 S cm − 1 between 300 °C and 450 °C.The present study confirmed the suitability of the ceramics as potential substrate material for LTCC applications. [ABSTRACT FROM AUTHOR]

Hydrogen energy possesses immense potential in developing a green renewable energy system. However, a significant problem still exists in improving the photocatalytic H 2 production activity of metal-free graphitic carbon nitride (g-C 3 N 4) based photocatalysts. Here is a novel Cu 3 P/CdS/g-C 3 N 4 ternary nanocomposite for increasing photocatalytic H 2 evolution activity. In this study, systematic characterizations have been carried out using techniques like X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM), Raman spectra, UV–Vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), surface area analysis (BET), electrochemical impedance (EIS), and transient photocurrent response measurements. Surprisingly, the improved 3CP/Cd-6.25CN photocatalyst displays a high H 2 evolution rate of 125721 μmol h−1 g−1. The value obtained exceeds pristine g-C 3 N 4 and Cu 3 P/CdS by 339.8 and 7.6 times, respectively. This could be the maximum rate of hydrogen generation for a g–C 3 N 4 –based ternary nanocomposite ever seen when exposed to whole solar spectrum and visible light (λ > 420 nm). This research provides fresh perspectives on the rational manufacture of metal-free g-C 3 N 4 based photocatalysts that will increase the conversion of solar energy. By reusing the used 3CP/Cd/g-C 3 N 4 photocatalyst in five consecutive runs, the stability of the catalyst was investigated, and their individual activity in the H 2 production activity was assessed. To comprehend the reaction mechanisms and emphasise the value of synergy between the three components, several comparison systems are built. Sphere-like Cu 3 P/CdS/g-C 3 N 4 photocatalyst was developed using hydrothermal route followed by ball milling and wet impregnation assisted method. A highest hydrogen production of 125721 μmol h−1g−1 was obtained for the above nanocomposite containing 6.25 wt% of g-C 3 N 4. [Display omitted] • Sphere-like Cu 3 P/CdS/g-C 3 N 4 composites was developed for visible light activity. • Metal free composites for H 2 evolution under visible light illumination was achieved. • The improved charge separation, transfer and transport results highest H 2 production. • Best activity results are observed for 3CP/Cd-6.25CN catalysts supported on g-C 3 N 4. • First time we report highest H 2 production activity for Cu 3 P/CdS/g-C 3 N 4 composites. [ABSTRACT FROM AUTHOR]

The present study aimed at developing an exopolysaccharide based nanoemulsion with increased kinetic stability, solubility, and availability. The nanoformulation was fabricated employing ultrasonication, a high energy fabrication method and constituted of flaxseed oil, tween 80, ethanol, and exopolysaccharide (extracted from Ganoderma gibbosum). The resultant formulation was found to have an average droplet size of 101.5 nm, with a PDI of 0.189, and a zeta potential of -8.2 mV. The particle size was further confirmed via the high resolution transmission electron microscopy which reported the nanoemulsion droplets to be round, uniform in size, with particle size ranging between 10 to 115 nm. In terms of the thermodynamic and storage stability the formulation was found to be highly stable and resistant to creaming, phase separation, and changes in pH. Further, the results in-vivo antioxidant assay revealed an increase in the activity of serum superoxide dismutase and catalase and a decrease in the serum level of thiobarbituric acid reactive substances suggesting that the formulation is capable of ameliorating the effect of reactive oxygen species in biological system. [ABSTRACT FROM AUTHOR]

Li–CdS/TiO 2 nanocomposite with different composition 10Li–CdS/TiO 2 , 20Li–CdS/TiO 2 , 30Li–CdS/TiO 2 , 40Li–CdS/TiO 2 , 50Li–CdS/TiO 2 were coated on FTO surface by using doctor blade followed by successive ionic layer adsorption and reaction (SILAR) method. As synthesized Li–CdS/TiO 2 photoanode is characterized with field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), high resolution transmission electron microscopy (HR-TEM), diffuse reflectance spectroscopy (UV-DRS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL). FE-SEM analysis suggests that, Li–CdS/TiO 2 film is 10.2 μm thick, porous, spongy and uniformly covered on FTO surface. The HR-TEM images reveal that the CdS nanoparticles are in intimate contact with the TiO 2 nanocrystal shells with the CdS/TiO 2 interfaces and the particle size of CdS and Li 2 S lies in the range of 20 nm–50 nm. UV-DRS analysis shows that, as the loading of Li in CdS/TiO 2 films increases, there is decrease in band gap energy. The XPS analysis supports the presence of Li+ in Li–CdS/TiO 2 nanocomposite. The PL spectra suggest that, with the increase in extend of Li+ ions into Li–CdS/TiO 2 , intensity of green emission band increases and it is shifted to higher wavelength. This reflects the low recombination rate of photo generated charge carrier in Li–CdS/TiO 2 which is responsible for higher photocatalytic H 2 production. The visible light photoanodic performance of Li–CdS/TiO 2 was investigated for H 2 evolution using aqueous Na 2 SO 3 and Na 2 S solution under natural sunlight. Among the all-synthesized nanocomposite material, the highest amount of hydrogen produced over 20Li–CdS/TiO 2 was found to be 38.61 ml/g/h in natural sunlight. Photoelectrochemical (PEC) performance of Li–CdS/TiO 2 was examined. A possible mechanism for photocatalytic hydrogen generation is also discussed. • Li–CdS/TiO 2 function as photocatalyst cum photoanode during solar water splitting. • Li–CdS/TiO 2 photoanode was synthesized by doctor blade followed by SILAR method. • Li–CdS/TiO 2 photoanode produces excellent H 2 as compare to TiO 2 and CdS/TiO 2. • In natural sunlight, 38.69 ml/g/h H 2 were evolved over 20Li–CdS/TiO 2. • 20Li–CdS/TiO 2 shows excellent transfer kinetics in PEC water splitting process. [ABSTRACT FROM AUTHOR]

As traditional non-renewable energy sources become scarcer, researchers are exploring effective strategies for producing sustainable and renewable energy. Oxygen evolution reaction through electrocatalytic water splitting (EC-OER) on the surface of a semiconductor has drawn much more attention in the worldwide as it has the principal role towards the several kind of energy applications viz. fuel cell, metal-ion rechargeable batteries and water oxidation. It is extremely difficult to develop eco-friendly, plentiful, and cost-effective nanomaterials as catalysts in order to achieve high efficiency of hydrogen production through water splitting. Furthermore, hierarchical nanostructures will become more valuable in future energy conversion applications due to their excellent physicochemical properties. Herein, we have synthesized total six different kinds of multi-metal-doped porous silica nanomaterials by utilizing the combination of nickel, iridium, and ruthenium metal slats in order to explore them as potential catalysts for electrochemical water oxidation process. We present a simple strategy to synthesize multi-metal-doped silica materials with spherical morphology, deploying a cation surfactant template (CTAB) as a structure directing agent in water-ethanol solvent mixtures. These materials are thoroughly characterized with the help of powder X-ray diffraction (PXRD), UV–Vis, FT-IR, X-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscopy (FE-SEM), nitrogen-sorption isotherm, thermogravimetric (TGA) analysis. The particles are 550–600 nm in size with a fine-looking spherical morphology and surface area in the range of 111–419 m2/g. Among all of these metal-silica, Ni–Ir–Ru-doped mesoporous silica particles (NIRS) exhibit excellent electrocatalytic activity towards oxygen evolution reaction (100 mA/cm2 current density@0.5V) with long-term durability up to 10 h, and the Tafel slope is also very low (∼68 mV/dec) in 1 M KOH medium. The excellent electrical conductivity of Ni–Ir–Ru-doped silica makes it a superior electrocatalyst due to its spherical morphology, synergistic effects of the multi metallic components, and its hierarchical nanoporous structure. [Display omitted] • A facile method for multi-metal-doped mesoporous silica was developed. • The particle sizes were 550–600 nm and surface area were up to 419 m2/g. • Multi-metal-doped mesoporous silica particles were spherical particles. • NIRS generated 100 mA/cm2 and current density@0.5V during OER in pH=14. • NIRS exhibited high durability up to 10 h with Tafel slope of 68 mV/dec in pH=14. [ABSTRACT FROM AUTHOR]

In the present work, bio-based conductive polymer composites were developed to utilize as supporting material for anode catalysts for oxidation of fuels to generate electrical energy. An in-situ method was adopted to synthesize the conducting polymer carbon composites through combined condensation process by reacting terephthalaldehyde and benzidine, and reinforced with almond shell carbon (BT-ASC). Using formaldehyde reduction method platinum-tin nanoparticles were deposited on BT-ASC composites and were characterized using modern analytical instruments., viz., X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDAX) and Fourier transform infrared spectroscopy (FT-IR). Thermal stability of the conducting polymer composites was analyzed by thermogravimetric analysis (TGA). The electrochemical properties of the prepared catalysts were studied by cyclic voltammetry and chronoamperometric analyses. Data obtained from different studies inferred that the Pt–Sn/BT-ASC catalyst possesses the maximum current density (88.6 mA/mg) with minimum oxidation potential than those of Pt–Sn/ASC, Pt/BT-ASC and Pt/ASC catalysts. The present work ascertains the importance of conducting polymer composites developed using reinforced with bio-carbon towards electro-oxidation of methanol and these supporting materials possess an enhanced catalytic activity than that of reported catalysts. • A bio-based conductive polymer composites as supporting material for anode catalysts. • Pt and Pt–Sn nanoparticles were developed by simple chemical reduction method. • Deducing jf/jb ratio, surface area and catalytic activity relationship of catalysts. • PtSn/BT-ASC, higher surface area and excellent catalytic activity. • PtSn/BT-ASC catalyst material for methanol fuel oxidation in acidic medium. [ABSTRACT FROM AUTHOR]

Noble metal single-atom catalysts (SACs) have been extensively investigated due to their unique electronic structure and high-efficiency catalytic performance. However, there are relatively few studies on the preparation of non-noble metal single atoms and their application in oxygen evolution reaction (OER). In this paper, nickel single-atom catalyst was prepared using a facile one pot method. Ni-SAC-2.5% showed uniform SACs distribution and anti-ferromagnetic property as evidenced by the aberration-corrected high resolution electron microscopy and the first-principle calculations, achieving the lowest overpotential of 220 mV (10 mA/cm2) and stable performance in 1 M KOH solution. Meanwhile, it exhibited the largest specific capacitance value of 1.77 mF/cm2 and the lowest charge transfer resistance value of 40.75 Ω due to the accelerated kinetic process. First-principle calculations further confirmed the lowest computed overpotential of 0.54 eV for Ni-SAC-2.5%. However, Ni small clusters and nanoclusters with superparamagnetic performance were observed when the Ni content was further increased to 3.5% and 4.5%, resulting in higher overpotentials of 0.85 eV and 2.01 eV for OER process as indicated by the theoretical simulation. This paper provides a facile method to prepare non-noble metal SACs and useful guidance for designing high performance OER catalysts. • Nickel single-atom catalyst was prepared using a facile one pot method. • Ni-SAC-2.5% showed uniform SACs distribution and anti-ferromagnetic property. • Ni-SAC-2.5% exhibited the lowest overpotential of 220 mV (10 mA/cm2) for OER process. • Ni-SAC-2.5% exhibited the largest specific capacitance value of 1.77 mF/cm2. • First-principle calculations confirmed the lowest overpotential of 0.54 eV for Ni-SAC-2.5%. [ABSTRACT FROM AUTHOR]

In this study, a novel cobalt-doped cerium oxide (CeO2)on reduced graphene oxide (rGO) substrate was successfully prepared through a hydrothermal method. The comprehensive characterization of the synthesized nanocomposite involved X-ray diffraction studies (XRD), Raman spectrum analysis, High Resolution Transmission Electron microscopy (HRTEM), and Field Emission Electron Microscopy (FE-SEM). The effective surface area of CeO2/rGO and Co-CeO2/rGO was determined using the Randles-Sevecik equation, revealing values of 4.02X10-5 cm2 and 6.35X10-5 cm 2, respectively. Cyclic Voltammetry (CV) was employed to investigate the electrochemical reversibility behavior, demonstrating promising results for Co-CeO2/rGO nanocomposite. Electrochemical impedance spectroscopy(EIS) further highlighted low charge transfer resistance (Rct) and enhanced double-layer capacitance (Cdl). Notably, the synthesized nanocomposite exhibited excellent electrocatalytic activity for methanol and formic acid oxidation in an acidic medium. Overall, this work provides valuable insights into the synthesis characterization, and electrochemical performance of Co-CeO2/rGO nanocomposite, showcasing their potential applications in energy-related processes. [ABSTRACT FROM AUTHOR]

The microstructure of nanostructured bainite formed by austempering in high-carbon silicon steel is characterized by high resolution electron microscopy. The results show that the bainitic sheaves consist of nanoscale subunits. The found kinds of crystal lattice distortions of each subunit in one bainite lath show clear difference. The latest generated subunit has most distortions. As the subunit grows up, the lattice distortion gradually gets relaxed. This indicates that the subunits form with high phase transformation strain energy, which causes severe lattice distortion. The results provide new experimental evidence on subjects relevant to the understanding of the mechanism of formation of bainitic ferrite. [ABSTRACT FROM AUTHOR]

The high explosive PBX 9502 undergoes irreversible expansion during thermal cycling ("ratchet growth"). Recent innovations in thermomechanical modeling via homogenization strategies are beginning to incorporate mesoscale information such as grain size, total porosity, and spatial distribution of voids and cracks. To generate a complete experimental data set to challenge and inform these models, PBX 9502 pellets were thermally cycled, cross-sectioned using ion polishing, and imaged in high resolution with scanning electron microscopy. Ratchet growth was found to drive expansion through microcracking. Microcracks were affected by agglomeration of crystals within the PBX. Virgin material showed greater ratchet growth than recycled material. [ABSTRACT FROM AUTHOR]

This study aims to clarify the growth process of the β-phase in Al-Mg-Si alloys from the point of view of morphological evolution. The orientation relationship, shape, growth process, misfit value, and interfacial condition between the β-phase and Al matrix were investigated using high-resolution transmission electron microscopy (HR-TEM), focused ion beam (FIB), and optical microscope (OM). In a previous study, the growth process and shape of the β-phase were determined using scanning electron microscopy (SEM). It was proposed that the truncated octahedron (8{111}, 6{100} facets) transforms into a hexahedron (6{100} facets). This study proposes that two new three-dimensional shapes of the β-phase exist between the truncated octahedron and hexahedron, and we identified the {111} β facets at the edges of the β-phase. We proposed the morphology evolution during the growth process of Mg 2 Si crystals and calculated the misfit to understand that the unstable {111} β facet has a higher misfit value compared to the {001} β and {011} β facets. Our observations provide insight into how they influence the behavior of Mg 2 Si crystals, which is crucial for predicting the microstructural evolution of Al-Mg-Si alloys and for designing materials with desired properties. • Investigated the morphology evolution of the β-phase in Al-Mg-Si alloys. • Explored β-phase orientation relationship, shape, and growth process using HR-TEM, FIB, and OM. • Discovered {111} β facets and proposed new three-dimensional shapes for the β-phase. • Calculated misfit values, revealing the instability of the (111) β facet compared to (001) β and (011) β facets. • Contributed to understanding microstructural evolution in Al-Mg-Si alloys and material design. [ABSTRACT FROM AUTHOR]

• Spinel ferrite N i 0. 4 + x Z n 0. 6 − x C e y F e 2 − y O 4 (0 ≤ x + y ≤ 0.3) were synthesized by a modified glycol-thermal process. • Correlation between saturation magnetization and the effective magnetic moments. • Crystallite sizes vary inversely with initial magnetic susceptibility. • Distinct strong correlation between inverse initial magnetic susceptibility and unit cell volume. • Compound N i 0. 4 Z n 0. 6 F e 2 O 4 exhibit best sensing characteristics. The spinel ferrite systems N i 0. 4 + x Z n 0. 6 − x C e y F e 2 − y O 4 (0 ≤ x + y ≤ 0.3) were synthesized by a modified glycol-thermal technique. X-ray diffractometer (XRD) confirmed formation of single phase cubic spinel structure with average crystallite sizes 8–21 nm. The crystallite sizes were found to be in agreement with the particle sizes obtained from the high resolution transmission electron microscopy (HRTEM) indicating formation of single domain nanoparticles. Scanning electron microscopy (SEM) showed a homogeneous spread of semi-spherical nanoparticles. Brunauer-Emmett-Teller (BET) revealed specific surface area ranging between 64 and 108 m2/g, while Barrett-Joyner-Halenda (BJH) showed the pore sizes varying between 48 and 126 nm. Cation distribution obtained from Rietveld refinement revealed all Ce3+ occupied B- sites whilst Ni2+, Zn2+, Fe3+ occupied both A and B sites. Magnetization measurements were performed using the vibration samples magnetometer (VSM). The saturation magnetization varied between 51 and 60 emu/g, while the coercivity dropped from 114 to 89Oe. The remnant magnetization varied between 3 and 12 emu/g. A correlation was observed between the saturation magnetization and the effective magnetic moments confirming cation distribution to be reliable. A strong correlation between initial susceptibility and unit cell volume was found. The crystallite sizes varied inversely with initial magnetic susceptibility. The magnetic characteristics of presented materials make them useful in high frequency device applications and has potential use as contrast agent in magnetic resonance imaging (MRI). 57Fe Mössbauer spectroscopy revealed the strengthening of ferromagnetic coupling. Gas sensing tests revealed a decrease in sensing response with the transition from paramagnetic state to ferromagnetic state. The N i 0. 4 Z n 0. 6 F e 2 O 4 sample showed the best sensing response to SO 2 at 100 °C compared to CO gas. However, at 150 °C the sample was more sensitive to CO gas than SO 2 gas. [ABSTRACT FROM AUTHOR]

• High temperature water combined with irradiation induces in oxidation of grain boundaries that weaken the boundaries. • Applied tensile stress enhances the rate of grain boundary oxidation. • Deformation induced dislocation channels create local stresses sufficient to crack a grain boundaryweakened by oxidation. • Fracture of the oxidized grain boundary allows for oxidation of the boundary beneath the crack tip. • Oxidation of silicon at the grain boundary forms highly soluble amorphous silica that aids crack extension via dissolution. Irradiation assisted stress corrosion cracking (IASCC) is a form of intergranular stress corrosion cracking that occurs in irradiated austenitic alloys. It requires an irradiated microstructure along with high temperature water and stress. The process is ubiquitous in that it occurs in a wide range of austenitic alloys and water chemistries, but only when the alloy is irradiated. Despite evidence of this degradation mode that dates back to the 1960s, the mechanism by which it occurs has remained elusive. Here, using high resolution electron backscattering detection to analyze local stress-strain states, high resolution transmission electron microscopy to identify grain boundary phases at crack tips, and decoupling the roles of stress and grain boundary oxidation, we are able to unfold the complexities of the phenomenon to reveal the mechanism by which IASCC occurs. The significance of the findings impacts the mechanical integrity of core components of both current and advanced nuclear reactor designs worldwide. [ABSTRACT FROM AUTHOR]

• An expected SnO 2 @CuO/CF heterostructure material is synthesized. • p-n heterojunction enhances the adsorption of H 2 O 2 and benefits sensing properties. • Cost-effective H 2 O 2 electrochemical sensor with excellent performance is obtained. • The developed sensor has good biocompatibility for real-time detection of H 2 O 2 released by living cells. Hydrogen peroxide (H 2 O 2) is a major messenger molecule in cellular signal transduction. It is critical to detect cellular secreted H 2 O 2 in situ for clinical diagnosis and biomedical research. Therefore a simple, fast, sensitive, and cost-effective hydrogen peroxide detection method is needed. In this study, copper foam (CF) was used as copper source and conductive substrate, the electrochemical sensor SnO 2 @CuO/CF is prepared to detect H 2 O 2 secreted by living cells. High resolution transmission electron microscopy (HRTEM), X-ray diffraction, Mott Schottky curves and X-ray photoelectron spectroscopy demonstrate the successful formation of SnO 2 @CuO heterostructure. Theoretical calculations confirm that SnO 2 @CuO heterostructure facilitates the adsorption of H 2 O 2. The designed SnO 2 @CuO/CF sensor shows good sensing performance for H 2 O 2. Under optimal conditions, the designed sensor shows a relatively wide linear range to H 2 O 2 concentration from 1 μM to 13.88 mM, with high sensitivity (5100 μA·mM−1·cm−2) and low detection limit (0.13 μM). Cytotoxicity experiments prove that the sensor has good biocompatibility and the prepared sensor is successfully used to detect H 2 O 2 released by HeLa cells. With superior sensitivity, anti-interference ability, and reproducibility, SnO 2 @CuO /CF shows the potential application of H 2 O 2 monitoring in the field of biomedical and clinical diagnosis. This study provides a new platform for the development of highly sensitive H 2 O 2 electrochemical sensors in practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Owing to the combination of good thermo-optical properties and inhomogeneously broadened fluorescence spectra suitable for ultrashort laser pulse generation, rare-earth doped solid solutions of sesquioxides (Y,Lu,Sc) 2 O 3 have attracted considerable interest in recent years. In this study, compositionally disordered Tm3+-doped YScO 3 transparent ceramic was fabricated using solid-state vacuum sintering of nanopowder produced using laser ablation of solid target in air flow. The as-synthesized powder consisted of weakly aggregated spherical particles having 20 nm diameter and a mostly monoclinic (space group C 2/ m) crystal structure, whose symmetry was transformed into cubic (space group Ia -3) by calcination at 1050 °C. From high resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray analysis (EDX), we observed a homogeneous distribution of components both throughout individual nanoparticles and 100-nm-thick ceramic foil resulting in high structural and optical quality of the obtained samples. The sintered ceramic featured an optical transmission of 77% at 600 nm and above 81% near 2 μm, an average grain size of 24.2 μm and a content of scattering centers of 26.1 ppm. The absorption spectra at several temperatures, from 93 K to 293 K, were measured and the corresponding absorption coefficients were obtained by Lambert-Beer formula in the range from 600 nm to 900 nm and from 1400 nm to 2100 nm. In particular, the room temperature absorption cross section at 794 nm and 1634 nm were determined to be σ abs = 4.25 × 10−21 cm2 and σ abs = 5.01 × 10−21 cm2 respectively. Concerning the emission cross section it was calculated by Fuchtbauer-Ladenburg equation starting from the fluorescence spectrum acquired at the laser work temperature: at 1951 nm and 2106 nm corresponding to the main two emission peaks belonging the curve, it was found σ em = 9.2 × 10−21 cm2 and σ em = 4.9 × 10−21 cm2, respectively. Finally, it was tested the laser behavior of the ceramic: pumped at 793 nm in quasi -CW mode it delivered 1.27 W of output power with a slope efficiency of 10.33% at 2081 nm. The tunability curve spans from 1942 nm to 2110 nm (i. e. 168 nm). • Tm 0.05 (Y 0.5 Sc 0.5) 1.95 O 3 laser ceramic. • Solid-state vacuum sintering from laser-ablated (Tm,Y,Sc) 2 O 3 nanoparticles. • Tm-based laser with emission peak at 2081 nm. • Broad laser wavelength tuning range (from 1942 nm to 2110 nm). [ABSTRACT FROM AUTHOR]

Pre-stretched strains, 2%, 4%, and 6%, were conducted on the friction-stir-welded dissimilar 2024-to-7075 aluminum alloy joints for strengthening purpose. Tensile tests and microhardness measurements were performed to evaluate the strengthening effect. Transmission electron microscopy and high resolution transmission electron microscopy examinations were employed to characterize precipitates and dislocation structures of the as-welded and pre-stretched joints to elucidate the intrinsic strengthening mechanisms. Results showed that the yield and tensile strengths of the pre-stretched 6% joint respectively increased 147.9 MPa and 31.1 MPa when compared with the as-welded joint. The strain hardening rates of 2024 lower hardness zone (LHZ)-II and 7075 LHZ were higher at the pre-stretched strain rate of 1 mm/min than those of 2 mm/min based on the microhardness area evolution. The yield sequence of the as-welded joint was 2024 LHZ-II, 2024 LHZ-I, 7075 LHZ, stir zone (SZ), and 2024 base material. The appearance of dislocation tangles, dislocation walls, dislocation cells, dislocation pile-ups in the 2024 LHZ-II and 7075 SZ combined with the severe interactions between dislocation structures and precipitates were the dominant strengthening factors. It was very interesting that dislocations provided a diffusion path for Mg atoms and Cu atoms in 2024 LHZ-II during the pre-stretching process. • Pre-stretching was used to strengthen the FSWed dissimilar aluminum alloys joints. • Yield sequence of the FSWed dissimilar aluminum alloys joints was identified. • The strengthened lower hardness zone contributed to the reinforced global joint. • Several kinds of dislocations structures induced by the pre-stretching process. • Dislocations provided a diffusion path for Mg and Cu atoms in 2024 aluminum alloy. [ABSTRACT FROM AUTHOR]

[Display omitted] • SnS and SnS 2 are synthesized in the form of quantum dots from aqueous solutions. • Syntheses are conducted under room conditions thanks to application of ultrasound. • Influence of sonication time on QDs properties is investigated. • SnS and SnS 2 QDs were utilized as photo- and (for the first time) sonocatalysts. • The greatest color removal was observed in the case of SnS QDs sonocatalyst (85.2%) Our study reports the ultrasound-assisted synthesis of SnS and SnS 2 in the form of nanoparticles using aqueous solutions of respective tin chloride and thioacetamide varying sonication time. The presence of both compounds is confirmed by powder X-ray diffraction, energy-dispersive X-ray spectroscopy, as well as Raman and FT-IR spectroscopic techniques. The existence of nanoparticles is proven by powder X-ray diffraction investigation and by high resolution transmission electron microscopy observations. The size of nanocrystallites are in the range of 3–8 nm and 30 50 nm for SnS, and 1.5–10 nm for SnS 2. X-ray photoelectron spectroscopy measurements, used to investigate the chemical state of tin and sulphur atoms on the surface of nanoparticles, reveal that they are typically covered with tin on the same oxidation degree as respective bulk compound. Values of optical bandgaps of synthesized nanoparticles, according to the Tauc method, were 2.31, 1.47 and 1.05 eV for SnS (60, 90 and 120 min long synthesis, respectively), and 2.81, 2.78 and 2.70 eV for SnS 2 (60, 90 and 120 min long synthesis, respectively). Obtained nanoparticles were utilized as photo- and sonocatalysts in the process of degradation of model azo-dye molecules by UV-C light or ultrasound. Quantum dots of SnS 2 obtained under sonication lasting 120 min were the best photocatalyst (66.9 % color removal), while quantum dots of SnS obtained under similar sonication time were the best sonocatalyst (85.2 % color removal). [ABSTRACT FROM AUTHOR]

β-Bi 2 O 3 and Ni-incorporated β-Bi 2 O 3 nanoparticles with different Ni incorporating amounts (0, 2, and 4 at. wt. %) were successfully synthesized through a viable hydrothermal process. As-synthesized nanoparticles were analyzed by complementary analytical tools such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), UV–visible spectroscopy (UV–Vis), and photoluminescence spectroscopy (PL) for structural, microstructural, compositional, and spectral properties. The photocatalytic performance of synthesized nanoparticles was assessed by subjecting them to visible light irradiation and monitoring the decomposition of rhodamine-B dye. The findings demonstrated that the inclusion of Ni(4%) in β-Bi 2 O 3 nanoparticles significantly enhanced its photocatalytic activity compared to pristine β-Bi 2 O 3 which is desirable for environmental remediation. This improvement may be caused by increased generation of electron-hole (e−-h+) pairs, reduced recombination rate of these pairs, enhanced absorption of visible light, and a decreased band gap energy. To evaluate the specific capacitance characteristics of synthesized electrode materials, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance analyses were conducted. The super capacitance activities of prepared electrode materials were observed in the order of Bi 2 O 3 < Ni(2%)-Bi 2 O 3 < Ni(4%)-Bi 2 O 3. Notably, Ni(4%)-Bi 2 O 3 nanocomposite exhibited higher supercapacitance, which can be attributed to the effective role of appropriate nickel incorporation in Bi 2 O 3. These results suggested that the incorporation of Ni(4%) into β-Bi 2 O 3 to form a nanocomposite showed greater capability as an effective electrode material for advanced energy storage devices, especially supercapacitors. Ni (0,2,4%) incorporated-Bi 2 O 3 nanoparticles were successfully synthesized and characterized through viable techniques. Ni (4%)- Bi 2 O 3 nanoparticles have shown enhanced visible light driven photocatalytic activity against organic dyes for environmental remediation. It also exhibited high supercapacitance desirable for high capacity electrode material employable in supercapacitors. [Display omitted] • Ag NPs-loaded brookite TiO 2 NWs supported on rGO sheets were produced hydrothermally. • Structure and morphology were evaluated by XRD, XPS and SEM/TEM. • Ag–TiO 2 /rGO nanohybrid exhibited an excellent light induced photocatalytic performance. • A suitable schematic mechanism was proposed for photocatalytic degradation of dye. • Ag–TiO 2 /rGO nanohybrid demonstrated fairly high electrochemical electrode material characteristics. [ABSTRACT FROM AUTHOR]

High manganese steel is influenced by the combined effects of corrosion and wear during service under specific conditions, resulting in components with shortened service life. Under harsh service environments, newly developed Cr+N alloyed austenitic high manganese steel (Mn18Cr7C0.6N0.2 steel) as a new type of railway steel has shown promising results. Herein, the tribocorrosion behaviors of Mn18Cr7C0.6N0.2 and Mn13C1.1 steels in artificial acid rain were studied using electrochemical methods, field emission scanning electron microscope (FE-SEM), focused ion beam scanning electron microscopy (FIB-SEM), scanning transmission electron microscopemicroscopy energy dispersive X-ray spectroscopy (STEM-EDS), and high resolution transmission electron microscopy (HR-TEM). The results showed the formation of passive film and gradient-nanostructure on surfaces of both test steels during tribocorrosion. A dense and tightly adhering amorphous passive film was formed on Mn18Cr7C0.6N0.2 steel surface with a superior blocking effect toward invasive ions. The high strain resistance and plasticity of the Mn18Cr7C0.6N0.2 steel resulted in an intact gradient-nanostructure, suitable for obtaining high surface hardness and maintaining the toughness of the matrix, contribute to providing high wear resistance. The oxide film on the Mn13C1.1 steel surface comprised crystal α-FeOOH. Vortex cracks formed in its gradient structure due to strain localization. Meanwhile, the relatively poor corrosion protection ability and vortex cracks of its gradient-nanostructure prevented it from maintaining interface integrity of the gradient nanostructure, resulting in inferior tribocorrosion resistance. In artificial acid rain, the new type of Cr+N alloyed Mn18Cr7C0.6N0.2 steel exhibited higher tribocorrosion resistance than traditional high manganese steel, promising for use as an excellent wear-resistant material under corrosive environments. • An amorphous passive film formed on the surface of Cr+N alloyed high-Mn steel. • The gradient-nanostructure of Cr+N alloyed high-Mn steel maintained integrity. • Vortex cracks formed in the gradient-nanostructure of traditional high-Mn steel. • Gradient-nanostructure and passive film determined the tribocorrosion resistance. • The surface layer and passive film were fully observed by FIB and TEM. [ABSTRACT FROM AUTHOR]

This paper presents the recrystallization of sodium bicarbonate (NaHCO 3) using the Supercritical AntiSolvent process. The focus is pointed toward crystal habit and its modification induced by varying the solvent nature. The observed habit is uncommon with crystals exhibiting a "zigzag" shape. High Resolution Scanning Electron Microscopy observations refuted that this shape was due to particle attachment: those "zigzag" particles are likely monocrystals grown in a diffusion-limited media. Firstly, a molecular modeling study shed light on organic solvents that can interact strongly with NaHCO 3 crystals. Such solvents were found to be ethylene glycol and glycine, in contrast to ethanol or water which likely interact weakly with NaHCO 3 crystals. An experimental campaign confirmed the predicted interactions. Ethylene glycol interactions with NaHCO 3 crystals led to the production of a different crystal salt. Alternatively, adding glycine as a growth inhibitor led to the initial polymorphic form, although with a modified growth mechanism. [Display omitted] • Sodium bicarbonate (NaHCO 3) recrystallized using the supercritical anti-solvent process. • Atypical "Zigzag" crystals formed, caused by an alternating growth direction. • Molecular modeling shows NaHCO 3 crystal interactions with Ethylene Glycol and Glycine. • Selective interactions of Ethylene Glycol with NaHCO 3 crystals allow for polymorphism control. • Strong Interactions of Glycine with NaHCO 3 crystals hinder the nucleation and growth. [ABSTRACT FROM AUTHOR]

ZrN and TiNiN nanolayers are alternately deposited on silicon substrate by magnetron sputtering. A series of ZrN/TiNiN nano-multilayer films with different Ni contents are prepared by varying the Ni:Ti volume ratio of the targets. The effects of Ni content on the microstructures and mechanical properties of ZrN/TiNiN nano-multilayer films are studied by X-ray diffractometer (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and nanoindentation instrument. The results show that with the increase of Ni content, the crystallization degree of ZrN phase first increases and then decreases. Besides, the hardness, elastic modulus and toughness of the films also increase first and then decrease with Ni content increasing. When Ni:Ti= 1:24, the ZrN/TiNiN nano-multilayer films obtain the highest hardness, elastic modulus and fracture toughness, which are 23.2 GPa, 317.8 GPa and 2.29 MPa·m1/2, respectively. This is mainly attributed to the best columnar crystal growth of the ZrN/TiNiN nano-multilayer film. The TiNiN layer changes into face centered cubic structure under the template of ZrN layer, and grows in coherent epitaxy with ZrN layer. ● A series of ZrN/TiNiN nano-multilayer films with different Ni contents are prepared by magnetron sputtering. ● When Ni:Ti= 1:24, the ZrN/TiNiN nano-multilayer films simultaneously obtain the highest hardness and fracture toughness. ● The high hardness and toughness are due to that the TiNiN layer grows in coherent epitaxy under the ZrN layer template. [ABSTRACT FROM AUTHOR]

[Display omitted] • The surface chemical composition of β-Ga 2 O 3 films is discussed in depth. • The component of O 1s with the binding energy around 531.8 eV is attributed to surface lattice O atoms. • The defects inside the β-Ga 2 O 3 films were analyzed by HRTEM. β gallium oxide (β-Ga 2 O 3) is an ultrawide bandgap semiconductor with great potential for solar-blind ultraviolet detection, power devices, and gas sensing. However, the understanding of the surface properties of β-Ga 2 O 3 remains insufficient. Here, epitaxial growth of β-Ga 2 O 3 films was carried by metal–organic chemical vapor deposition (MOCVD) on sapphire substrates. The surface chemical composition, surface layer crystalline properties, and surface morphology of the β-Ga 2 O 3 films were discussed and analyzed in detail. By comparing the atomic ratios of O/Ga, the surface morphology, and the crystalline properties of the films, we attribute the component of O 1s with the binding energy around 531.8 eV to surface lattice O atoms. Moreover, the one-dimensional defects inside the surface layers and the near-interface regions of the films were observed at atomic scale by high resolution transmission electron microscopy (HRTEM). By comparing the lattice fringes of different facets, the geometric phase uniformity, and the distribution of strain, we found that the crystalline quality of the surface layers is much higher than the near-interface regions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cerium substituted HA at different concentrations were prepared and characterized. • The antimicrobial study of prepared samples showed effective antimicrobial action. • The biocompatibility test demonstrated that all prepared samples were nontoxic. • The prepared materials have high potential to employ as drug delivery systems. • Cerium substituted HA can be used as a local treatment of bone cancer. The current study used the precipitation method to prepare pure calcium hydroxyapatite (HA) and cerium-substituted hydroxyapatite (Ce-HA) nanoparticles, where cerium ions were exchanged into the HA structure at different concentrations ranging from 3 to 7 wt%. X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), Fourier transform infrared (FTIR) spectroscopy, Brunauer-Emmett-Teller (BET) surface area measurements, and zeta potential were used to examine the structural characteristics of the nanoparticles. Additionally, the antibacterial and antifungal effects of the produced materials on Gram-positive, Gram-negative, and fungal bacterial species were studied. Nanoparticles with cerium doping showed effective antibacterial and antifungal properties. All samples were tested for bioactivity in simulated body fluid (SBF), and the formation of an apatite layer on their surfaces was highlighted using SEM in conjunction with energy-dispersive X-rays (EDX).Doxorubicin (DOX) release from Ce-HA nanoparticles and pure HA was tested in phosphate-buffered saline (PBS) for up to 28 days. Both nanoparticles were able to release the drug while still being semi-fully loaded. Similarly, the cytotoxic effect of all produced samples on the MG-63 cell line was evaluated, and all samples showed good cytocompatibility. The cytotoxic effect of doxorubicin-loaded nanoparticles showed promising anticancer activity against bone cancer cells, especially samples with high cerium content. The resulting nanoparticles show excellent promising ability for the delivery of doxorubicin to bone cancer with the capacity for bone regeneration. [ABSTRACT FROM AUTHOR]

Boron doped diamonds (BDD) with boron concentration above 1019 at./cm3, grown under conditions of high isostatic pressure by the temperature gradient method, were studied by Transmission Electron Microscopy methods, EELS analysis and X-ray diffraction analysis. It was shown that boron is distributed unevenly in the grown crystal. It was found that in places of maximum boron content, interplanar distances d 111 increase from 0.206 to approximately 0.2065 nm. Parallel bands were discovered, the boundaries of which are fragments of the intermediate carbon phase (ICP-phase). Numerous twins along the {111} plane, as well as fragments of rhombohedral 9R phase, were discovered. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu2+ doped MgFe 2 O 4 have been synthesized by microwave combustion method. • Cu2+ doped MgFe 2 O 4 confirms cubic inverse spinel structure with Fd 3 ¯ m space group. • Structural and elementals are confirmed by XRD, XPS and EDX analysis for MgFe 2 O 4. • Hysteresis confirms Mg 1- x Cu x Fe 2 O 4 were shows a ferromagnetic behaviour in nature. • The detailed photocatalytic degradation mechanism of Mg 0.7 Cu 0.3 Fe 2 O 4 is discussed. This study presents the synthesis of Mg 1- x Cu x Fe 2 O 4 (x = 0.0, 0.1, 0.3, and 0.5) nanoparticles (NPs) using the direct microwave combustion method (MCM) with L-arginine as the fuel source. The samples were characterised comprehensively using various analytical techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), High resolution scanning electron microscopy (HRSEM), Energy-dispersive X-ray (EDX), Diffuse reflectance spectroscopy in the ultraviolet–visible (DRS-UV) range, Fourier-transform infrared spectroscopy (FTIR), and Vibrating sample magnetometry (VSM). The cubic spinel structure was verified by X-ray diffraction analysis. It revealed an average crystallite size ranging from 15.8 to 26.6 nm. The oxidation states and elemental composition of Mg 1- x Cu x Fe 2 O 4 were evaluated using XPS analysis. Notably, the major absorption bands at 557 and 434 cm−1 corresponded to the tetrahedral (Mg2+ –O2−) and octahedral (Fe3+ –O2−) sites, respectively. HRSEM images showed agglomerated particles with elemental verification of Mg 1- x Cu x Fe 2 O 4. This was validated by EDX studies. The optical bandgap was determined by DRS-UV analysis. Functional groups were analyzed by FTIR spectra. Hysteresis loop measurements revealed the ferromagnetic properties of the obtained samples. Furthermore, the study evaluated the detailed mechanism of the photocatalytic degradation (PCD) of Mg 0.7 Cu 0.3 Fe 2 O 4. [ABSTRACT FROM AUTHOR]

Structural analysis, spectroscopic studies and multiferroic properties of Zn 1- x Ni x O (x = 0, 0.03, 0.06, 0.09, 0.12, 0.15) nanoparticles are reported here. Ni-doped ZnO nanoparticles were synthesized through a simple chemical growth route using hydroxyoxalate type materials. The hexagonal wurtzite structure of prepared compounds has been ascertained through X-ray diffraction. High Resolution Transmission Electron Microscopy (HRTEM) reveals the particle size and lattice growth direction of the nanoparticles. The expected doping concentration of nickel was confirmed by Energy Dispersive X-ray (EDX) spectroscopy. The excitonic peaks observed from absorption spectra of the prepared nanoparticles exhibit blue shift for nickel doping. Ni-doped ZnO explore superior photocatalytic response and are controlled by three factors: band gap, crystallite size and surface defect. To be specific, 12 % Ni doping results in 7.8 times increase in the photocatalytic degradation efficiency. The samples exhibit characteristic P -E and M − H loops. The obtained remnant polarization for 9 % and 15 % Ni doping are 9 × 10−3 and 6 × 10−3 μC/cm2 respectively. The multiferroicity perceived in the synthesized Ni-doped ZnO nanoparticles with the ME coefficient at around 1.1mV/cm-Oe have important application potentiality in electromagnetic coupled devices. • Ni-doped ZnO nanopowders for tuning the physical properties as multiferroicity. • Prominence of absorption in UV-VIS due to exciton-exciton collision. • Superior sunlight-driven photocatalytic effect of Ni-doped ZnO nanoparticles. • Signature of multiferroic behavior in nickel doped ZnO materials. • Magnetic and magnetoelectric properties of nickel doped ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

• Crystallization kinetics of chalcogenide glasses were studied through impulse excitation technique (IET). • High resolution transmission electron microscopy (HRTEM) confirmed the formation of nanocrystals. • The early crystallization has positive impact on microhardness and infrared transmittance. Chalcogenide glasses (ChGs) have been used in industry and our daily lives as infrared optical elements. Their crystallization kinetics must be investigated because a high level of crystallinity deteriorates the optical performance of glasses. In this study, the crystallization kinetics of ChGs were investigated by using the impulse excitation technique (IET), in which crystallization kinetics was probed based on the increases in Young's modulus at an annealing temperature, T a , higher than their glass transition temperature, T g. It is shown that crystallization can occur at a temperature 148 °C lower than that determined based on calorimetry. The Mori-Tanaka (MT) method was employed to estimate the volume fraction of crystals under different annealing temperatures, and the activation energy of crystallization was also calculated based on the crystallization rate. This early crystallization leads to Se-rich nanocrystals with sizes well below 10 nm. They led to higher microhardness without affecting infrared transmittance. This study provides new insights for the investigation of crystallization kinetics of materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • N-doped Cdots synthesized by conjugation of 1,4 butanediol L-arginine. • Self-assembly of amine functionalized transverse oligomeric chain of diols by H-bond. • Dual probe for the detection of nanomolar concentrations of TC and 4-NP. • Static quenching with ground state complexation between N-Cdots and TC /4-NP. • Demonstration of TC and 4-NP detection in real sample matrix: river water and milk. Nitrogen doped carbon dots are emerging as efficient photoluminescent probes for wide range of sensing applications. A simple strategy of synthesizing highly ordered nitrogen doped carbon dots (named here as N-CD arg) is developed by thermal conjugation of 1, 4-Butanediol with L-Arginine. It led to formation of self-assembled transverse carbon chains through oligomerization of 1,4-Butanediol and conjugation with L-Arginine. The structural, morphological and compositional analysis of the N-CD arg is confirmed from 1H and 13C NMR, mass spectroscopy, FT-IR, higher resolution transmission electron microscopy and X-ray photoelectron spectroscopy. It exhibited bright bluish photoluminescence with PL quantum yield of 11 %. Under optimized pH and contact time, the probe solution of N-CD arg exhibited dual sensing for the detection of tetracycline (TC) and 4-nitrophenol (4-NP) via PL quenching proportional, which followed Stern-Volmer relation. The linear PL quenching response for TC is in the range of 0.5 μM to 60 μM with a limit of detection (LOD) of 103 nM; while the linear range for 4-NP is 0.4 μM to 20 μM, and the LOD is 77 nM. Selectivity of these species have been confirmed against several metal ions, anions, other antibiotics (for TC detection) and different structural analogues of phenols (for 4-NP detection). The ability of the probe to quantitatively detect trace concentrations of TC and 4-NP in real sample matrices like river water and milk has been demonstrated by spike analysis. The mechanism of PL quenching of N-CD arg by TC and 4-NP has been discussed using PL decay lifetime spectroscopy. [ABSTRACT FROM AUTHOR]

In this research, cuprous oxide (pristine Cu 2 O) and rGO (reduced graphene oxide)-doped Cu 2 O were prepared using a simple synthetic route and adopted as sensitive materials for ozone detection. The microstructural, morphological and compositional properties of as-prepared samples have been analyzed by several characterization techniques including X-ray diffraction (XRD), High resolution transmission electron microscopy (HRTEM), Energy dispersive spectrometer (EDS), UV-Visible spectrophotometer (UV–vis), Multi-functional field emission scanning electron microscope (FESEM), X-ray Photoelectron Spectroscopy (XPS) and Brunauer-Emmett-Teller (BET). Meanwhile, the sensing features of as-prepared samples have been investigated carefully and the as-prepared 0.5 wt% rGO-Cu 2 O exhibited best ozone sensing properties, such as high stability, sensitivity and selectivity. It can be found that the response value of 0.5 wt% rGO-Cu 2 O-based sensor towards 20 ppb ozone and 1 ppm ozone were 9.2/1734, respectively, and the corresponding response and recovery times were 11/64 s and 11/411 s, respectively. More importantly, the detection limit of the 0.5 wt% rGO-Cu 2 O sensor was as low as 0.1 ppb. Furthermore, the possible mechanism for the enhanced sensing performance of the as-prepared rGO-Cu 2 O has been discussed. • We report rGO-Cu 2 O nanomaterials for efficient ozone gas detection. • O 3 gas sensing with very low detection limit at 0.1 ppb. • Advantages of the detection of O 3 at low interferences and well stability. [ABSTRACT FROM AUTHOR]

Removing carbon monoxide with catalytic combustion technology is an effective and economical solution. Highly efficient conversion of CO at low temperatures can be achieved by introducing a catalyst, and its application in automotive exhaust emissions and preferential oxidation of CO in fuel cells is remarkable. In this work, catalysts were prepared by mixing the prepared cerium organic framework with Co 3 O 4 , and after calcination at 400 °C, the organic framework collapsed, resulting in a uniform dispersion of Ce on the Co 3 O 4 nano surface. Experimental results demonstrated that the required temperature of the catalyst is 101 °C when the conversion is 90 %, and it remained stable over the 75 h tested at 100 °C. High resolution transmission electron microscopy (HRTEM) revealed that Ce/Co 3 O 4 primarily exposed 311 surface. Combined with DFT calculations, the catalysts may improve the catalytic combustion activity of CO by multiplying the oxygen vacancies and modulating the dispersion of Ce atoms. The reaction occurred on the 311 surface predominantly. Activated CO* preferred to react with the lattice oxygen at the Ce-O-Co linkage compared to the lattice oxygen at Co-O-Co. Energy barrier for the rate dictating step in the complete catalytic cycle is 0.42 eV. This work not only provides experimental support and theoretical basis for the design of low-temperature catalytic combustion CO catalysts, but also provides new ideas for the doping of metal oxides with lanthanide metals. [ABSTRACT FROM AUTHOR]

In this study, the effects of applied pressure (AP) and residual heat quenching (RQ) on the mechanical properties and thermal conductivities of Al-4.6Mg-3.6Zn-0.86Mn-0.48Fe alloys were investigated based on intensively microstructure analysis by scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM) and synchrotron X-ray tomography (SXT). The results indicated that AP and RQ did not change the type of intermetallic; instead, they reduced the length and quantity of lath-like Al 6 (Fe,Mn) and significantly refined the grain by increasing the cooling rate. Moreover, η′ precipitation particles were enriched near the grain boundaries, which was beneficial for the yield strength of the alloy; the AP + RQ sample exhibited the best mechanical properties of the ultimate tensile strength, yield strength and elongation of 269 MPa, 164 MPa and 11.4 %, respectively, which were 19 %, 17 %, and 83.8 % higher than those of the gravity cast (GC) sample. Moreover, the thermal conductivity of the AP + RQ sample did not show significant changes, which were attributed to the reduction in solid solute caused by the increased volume fraction of η′ precipitates, thus improving the thermal conductivity; however, the formation of numerous semi-coherent interfaces between η′ and the matrix led to increased lattice distortion, resulting in electron scattering. • Residual heat quenching can improve the strength of cast Al–Mg–Zn alloys. • The 3D morphology of the Fe-rich phases and pores has been significantly improved. • Mechanical properties enhanced by improvement of Al 6 (FeMn) and the presence of η'. • The semi-coherent interfaces between η′ and matrix reduced the thermal conductivity. [ABSTRACT FROM AUTHOR]

Methyl orange (MO), which is known as a highly durable dye that is extremely toxic to humans and animals, has been processed by using various methods. In recent years, MO degradation through reduction in the presence of NaBH 4 (NB) and suitable nanocatalyst have garnered considerable interest. However, the nanosized particles of the catalyst make separation from the liquid solution more difficult and limit the practical application of this technique. Herein, copper nanoparticles (CuNPs) decorated on three-dimensional chitosan aerogel (CSA) were synthesized as a reusable composite for the catalytic degradation of MO by using a green method with durian (Durio zibethinus) shell (DS) extract as a reducing agent. The Cu/CSA composite's physicochemical properties were characterized by using X-ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy- energy dispersive X-ray spectroscopy (SEM-EDS), high resolution Transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) and Raman spectroscopy. These modern techniques elucidated the structure and formation of copper nanoparticles on the CSA surface. The copper nanocatalysts have an average particle size of 32.6 nm, specific surface area of 55.8 m2/g, pore size of 32 Å and pore area of 0.049 cm3/g. Through the investigation of catalyst activity, the conditions of MO reduction were optimised with the 1.0 Cu/CSA sample, catalyst dose of 0.5 g/L and a molar ratio of MO/NB of 1/200. The reaction reached over 94.3% efficiency after 10 min, correlating with a kinetic rate constant of 0.163 min−1. It is worth mentioning that the optimized catalyst can be conveniently synthesized and retrieved from the reaction solution in just 5 s using a vacuum filter. Furthermore, its effectiveness remains largely unaffected even after undergoing five cycles of reuse, thus demonstrating its exceptional durability and potential in environmental remediation. [Display omitted] • An alternative chitosan aerogel-based support for metal nanoparticles. • Nano-copper/chitosan aerogel (Cu/CSA): a benign reduction using durian shell extract. • Outstanding reactivity of Cu/CSA in the catalytic reduction of methyl orange. • High stability and proficient reusability of Cu/CSA during 5 consecutive cycles. [ABSTRACT FROM AUTHOR]

The persistence of active pharmaceutical ingredients in water bodies has lead to detrimental impacts on public health as well as deteriorated aquatic resources at breakneck pace. To address this, highly fluorescent chitosan capped ZnS QDs (CZS QDs) were integrated with nickel ferrite nanoparticles (NF NPs) through ultrasonic assisted method to yield a series of magnetically responsive CZS-xNF nanohybrids (x = 5, 10, 15 and 20 wt% of NF). The successful fabrication of nanohybrids were affirmed through various techniques such as Fourier transform infra-red spectroscopy (FT-IR), powder X-ray diffraction (XRD), X-ray photoelectron microscopy (XPS), high resolution transmission electron microscopy (HRTEM), vibrating sample magnetometer (VSM) and diffused reflectance spectroscopy (DRS). The dual applicability of CZS-xNF nanohybrid was witnessed for the detection of pharmaceutical waste by fluorescence sensing and their concomitant annihilation via visible light driven photodegradation reactions. The developed nanohybrid showed exceptional selectivity towards tetracycline antibiotics, with ultra-low limit of detection of 0.53 μM for tetracycline (TC) and 0.30 μM for minocycline (MC), respectively. The fluorescent sensor was also analysed for trace level detection of tetracyclines in real water samples that showed satisfactory recoveries of 90–106%, depicting practical applicability of sensor. Additionally, the excellent photocatalytic features of synthesized nanohybrid prompted their use in photodegradation of TC and MC and a superior photocatalytic performance was achieved in comparison to CZS QDs. The enhanced photocatalytic performance of CZS-xNF nanohybrid can be attributed to type-I charge transfer mechanism, which resulted in efficient charge separation and reduced photo-induced recombination rate of charge carriers. The nanohybrids were recyclable up to four cycles after being utilized in sensing and photocatalysis, thus offering a promising strategy for environmental remediation through synchronized sensing and extirpation of pharmaceutical waste. The multifunctional magnetically retrievable CZS-xNF nanohybrids (x = 5, 10, 15 and 20 wt% of NF NPs) were designed by integrating highly fluorescent chitosan capped ZnS QDs (CZS QDs) and magnetic NiFe 2 O 4 nanoparticles (NF NPs) for detection and photocatalytic removal of pharmaceutical drugs, tetracycline and minocycline. [Display omitted] • Fabrication of photostable and biocompatible CZS-xNF nanohybrid using sonication method. • Uniform anchoring of CZS QDs onto the surface of NF NPs in CZS-xNF nanohybrid. • Ultralow level sensing and annihilation of pharmaceutical drugs, tetracycline and minocycline. • Sensitive and specific detection of tetracycline and minocycline in real water samples. • Excellent recyclability of CZS-10NF upto four sensing and photocatalytic cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • A wet impregnation procedure was used to create a g-C3N4/CuS heterojunction. • The catalyst degrades the RhB dye photocatalytically (98.6%) in 40 min. • The results of the repeatability experiment indisputably show that the produced catalyst has a high photo-stability. The g-C 3 N 4 /CuS heterojunction was synthesized using a wet impregnation process. Powder X-ray diffraction (PXRD), High resolution scanning electron microscopy (HR-SEM), X-ray photoelectron spectroscopy (XPS), Diffused reflectance spectroscopy (UV–vis DRS), and Photoluminescence (PL) were employed to examine the crystalline structure, morphology, elemental configuration, optical absorption characteristics, electron hole recombination, and charge transfer property of the prepared materials, respectively. The specific surface area and pore volume of the produced materials were calculated using N 2 adsorption–desorption isotherms and BET studies. Rhodamine B (RhB) is broken down by the catalysts in the presence of visible light. In 40 min, the catalyst showed quick photocatalytic degradation of the RhB dye (98.6 %). The synthesized catalyst performs at the highest level for photocatalytic degradation due to its low e-h recombination rate, broad spectrum of absorption light, increased photo-generated electrons, and larger specific surface area. Higher photocatalytic activity might be a result of the matched overlapping band structure and the interaction between CuS and g-C 3 N 4. The photoluminescent spectra show that the interaction of g-C 3 N 4 and CuS would not only boost the optical absorption property of g-C 3 N 4 , but would also produce more interfaces for the efficient transfer of photo-generated electron-hole pairs to limit recombination. The repeatability experiment's results unequivocally demonstrate that the developed catalyst has a high photo-stability. The results of the degrading efficiency tests were competitive with numerous photocatalysts that had already been published. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) by green synthesis from fungi polysaccharides are attracting increasing attention owing to their distinctive features and special applications in numerous fields. In this study, a cost-effective and environmentally friendly biosynthesizing AgNPs method with no toxic chemicals involved from the fruiting body polysaccharide of Phlebopus portentosus (PPP) was established and optimized by single factor experiment and response surface methodology. The optimum synthesis conditions of polysaccharide-AgNPs (PPP-AgNPs) were identified to be the reaction time of 140 min, reaction temperature of 94 °C, and the PPP: AgNO 3 ratio of 1:11.5. Formation of PPP-AgNPs was indicated by visual detection of colour change from yellowish to yellowish brown. PPP-AgNPs were characterized by different methods and further evaluated for biological activities. That the Ultraviolet-visible (UV–Vis.) spectroscopy displayed a sharp absorption peak at 420 nm confirmed the formation of AgNPs. Fourier transform infrared (FTIR) analysis detected the presence of various functional groups. The lattice indices of (111), (200), (220), and (331), which indicated a faced-centered-cubic of the Ag crystal structure of PPP-AgNPs, was confirmed by X-ray diffraction (XRD) and the particles were found to be spherical through high resolution transmission electron microscopy (HRTEM). Energy dispersive X-ray spectroscopy (EDS) determined the presence of silver in PPP-AgNPs. The percentage relative composition of elements was determined as silver (Ag) 82.5 % and oxygen (O) 17.5 % for PPP-AgNPs, and did not exhibit any nitrogen peaks. The specific surface area of PPP-AgNPs was calculated to be 0.5750 m2/g with an average pore size of 24.33 nm by BET analysis. The zeta potential was −4.32 mV, which confirmed the stability and an average particle size of 64.5 nm was calculated through dynamic light scattering (DLS). PPP-AgNPs exhibited significant free radical scavenging activity against DPPH with an IC 50 value of 0.1082 mg/mL. The MIC values of PPP-AgNPs for E. coli , S. aureus , C. albicans , C. glabrata , and C. parapsilosis are 0.05 mg/mL. The IC 50 value of the inhibition of PPP-AgNPs against α -glucosidase was 11.1 μg/mL, while the IC 50 values of PPP-AgNPs against HepG2 and MDA-MB-231 cell lines were calculated to be 14.36 ± 0.43 μg/mL and 40.05 ± 2.71 μg/mL, respectively. According to the evaluation, it can be concluded that these green-synthesized and eco-friendly PPP-AgNPs are helpful to improve therapeutics because of significant antioxidant, antimicrobial, antidiabetic, and anticancer properties to provide new possibilities for clinic applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Over the years, a wide range of spectral research has been carried out on various carbon forms to explore deeply their structure-property relationship. The structural stability of carbon allotropies remains to be a challenging endeavor yet to be achieved under extreme conditions, especially under acoustical shocked conditions. From the experimental findings, we report the acoustic shock wave response of the amorphous carbon nanoparticles and the resultant degree of crystalline nature, morphological characteristics and magnetic response. Moreover, analytical techniques such as X-ray diffractometry (XRD), Raman spectrometer, High resolution transmission electron microscopy (HR-TEM) and vibrational sample magnetometer (VSM) have been employed to arrive at the relationships of structure – morphology – magnetic properties under shocked conditions. Interestingly, under shocked conditions (0, 250, 500 and 750 shocks), compelling evidence has been found for the short-range amorphous pockets which turn into spatially short-range ordered graphitic domains within the sphere-shaped amorphous nanoparticles whereby the obtained values of the ratio I D /I G of the samples are 0.94, 0.93, 0.95 and 1.01 for 0, 250, 500 and 750 shocked conditions, respectively. Moreover, the saturation magnetization is found to have reduced in the base of the local atomic ordering and the obtained values are found to be 1, 0.64, 0.41, 0.725 emu/g for 0, 250, 500 and 750 shocked conditions, respectively. The structure-property relationship is to be elaborated in the upcoming sections. [Display omitted] • Shock wave induced amorphous carbon to short-range ordered graphitic domains is reported. • The I D /I G intensity ratio of the samples is 0.94, 0.93, 0.95 and 1.01 for 0, 250, 500 and 750 shocked conditions. • The saturation magnetization values are 1, 0.64, 0.41 and 0.725 for 0, 250, 500 and 750 shocked conditions. • The correlation of the magnetic properties and degree of crystalline nature is discussed. [ABSTRACT FROM AUTHOR]

Co-loaded amorphous zeolite has been prepared, characterized and tested as an electrochemical supercapacitor. Amorphous zeolite (AZ) and H-amorphous zeolite were prepared using the steam assisted crystallization method; the H+ was added on AZ via ion exchange with NH 4 NO 3 to evaluate the supercapacitive difference between AZ and H-AZ. Co was loaded into the AZ and H-AZ by the impregnation method to enhance the redox properties. The physico-chemical properties of the AZ, H-AZ, Co/AZ and Co/H-AZ were investigated using various analytical characterization techniques, namely X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR), High Resolution Scanning Electron Microscopy (HRSEM), N 2 physisorption and X-ray Photoelectron Spectroscopy (XPS). The materials were subsequently drop-cast into a Ni foam and evaluated for supercapacitive properties. Notably, the resulting electrode materials exhibit supercapacitive behaviour that is effective over a potential window from −0.1 to +0.7 V in a potassium hydroxide (1 M KOH) aqueous electrolyte. A relatively high specific capacitance of 550 F/g at 1 A/g was calculated from Galvanometric Charge Discharge (GCD) analysis for the Co/H-AZ electrode with a Coulombic efficiency of 98% after 2000 cycles and a capacitance retention of 91.6%, while the value calculated for Co/AZ was 400 F/g with a Coulombic efficiency of 96% after 2000 cycles and a capacitance retention of 75.5%. The energy density and power density for Co/H-AZ were 19.09 W h/kg and 250 W/kg respectively, while the energy density and power density for Co/AZ were 13.88 W/kg and 248 W h/kg respectively. The difference in the performance of Co/H-AZ and Co/AZ can be attributed to the effect of H+ ions at the electrode/electrolyte interface. [Display omitted] • Amorphous zeolite (AZ) was synthesized by the steam-assisted method; H was ion exchanged into AZ. • Co was loaded onto the AZ and H-AZ and then drop cast onto Ni-foam. • Specific capacitance of Co/H-AZ and the Co/AZ: 550 and 400 F/g respectively. • After 2000 cycles, Co/H-AZ exhibited 98% Coulombic efficiency and 91.6 of capacitance retention. • Supercapacitor properties of Co/H-AZ are due to redox nature of Co 3 O 4 and H+ in AZ. [ABSTRACT FROM AUTHOR]