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Two series based on poly(propylene 2,5-furandicarboxylate)-block-poly(tetramethylene oxide) (PPF-b-F-PTMO) containing carbon and mineral nanofillers that differ in shape (1D and 2D) were synthesized via in situ polymerization. The influence of the addition of the 1D-type nanoparticle, i.e., carbon nanofibers (CNFs) and halloysite nanotubes (HNTs), and the so-called 2D-type, i.e., graphene nanoplatelets (GNPs) and organoclay (C20A), on the properties of a biobased block copolymer was analyzed. The dispersion of nanoadditives in the nanocomposites was determined using a scanning electron microscope (SEM). The thermal properties were studied employing differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The introduction of nanoparticles increased the crystallinity (Xc) and the mean values of tensile modulus (E) of the bionanocomposites. In turn, one observed that the decrease in the limited viscosity number (LVN) was visible along with incorporating nanoadditives. The synthesized polymer bionanocomposites reveal the mechanical properties of elastomers during mechanical testing. Moreover, the good processability of the obtained materials by injection molding combined with the comprehensive ability to change mechanical and thermal properties of PPF-b-F-PTMO by tailoring the type and content of the nanofillers can indicate their possible applications in packaging, automotive, sports, construction, and many other industries. [ABSTRACT FROM AUTHOR]

In this study, zinc oxide nanoparticles (Zn-NPs) were prepared by the green synthesis method and loaded inside niosomes as a drug release system and their physicochemical and biological properties were determined. Zn-NPs were prepared by the eco-friendly green strategy, the structure, and morphological properties were studied and loaded into niosomes. Subsequently, different formulations of niosomes containing Zn-NPs were prepared and the optimal formulation was used for biological studies. Scanning electron microscope (SEM) and dynamic light scattering (DLS) were used to investigate the morphology and size of nanoparticles. Fourier transform infrared spectroscopy (FTIR) and UV–Vis were used to confirm the synthesis of Zn-NPs. Energy dispersive X-ray spectrometer (EDS) determined the elemental analysis of the Zn-NPs synthesis solution and the crystalline structure of Zn-NPs was analysed by XRD (X-Ray diffraction). Furthermore, Zn-NPs were loaded inside the niosomes, and their structural characteristics, entrapment efficiency (EE%), the release profile of Zn-NPs, and their stability also were assessed. Moreover, its antimicrobial properties against some microbial pathogens, its effect on the expression of biofilm genes, and its anticancer activity on the breast cancer cell lines were also determined. To study the cytocompatibility, exposure of niosomes against normal HEK-293 cells was carried out. In addition, the impact of niosomes on the expression of genes involved in the apoptosis (Bcl2, Casp3, Casp9, Bax) at the mRNA level was measured. Our findings revealed that the Zn-NPs have a round shape and an average size of 27.60 nm. Meanwhile, UV–Vis, FTIR, and XRD results confirmed the synthesis of Zn-NPs. Also, the EE% and the size of the optimized niosomal formulation were 31.26% and 256.6 ± 12 nm, respectively. The release profile showed that within 24 h, 26% of Zn-NPs were released from niosomes, while in the same period, 99% of free Zn-NPs were released, which indicates the slow release of Zn-NPs from niosomes. Antimicrobial effects exhibited that niosomes containing Zn-NPs had more significant antimicrobial and anti-biofilm effects than Zn-NPs alone, the antimicrobial and anti-biofilm effects increased 2 to 4 times. Cytotoxic effects indicated that when Zn-NPs are loaded into niosomes, the anticancer activity increases compared to Zn-NPs alone and has low cytotoxicity on cancer cells. Niosomes containing ZnNPs increased the apoptosis-related gene expression level and reduced the Bcl2 genes. In general, the results show that niosomes can increase the biological effects of free Zn-NPs and therefore can be a suitable carrier for targeted delivery of Zn-NPs. [ABSTRACT FROM AUTHOR]

Lately, children's daily consumption of some products, such as cereals and candies, has been rising, which provides a compelling rationale for determining any metallic substances that may be present. Monitoring the concentration of certain metals, like nickel, in these products is necessary due to medical issues in humans when consumed regularly. So, in this work, a novel and highly selective carbon paste as a Ni(II) ion-selective sensor was prepared and investigated using ceramic magnesium aluminum spinel nanoparticles as the ionophore and tritolyl phosphate (TOCP) as a plasticizer. A modified co-precipitation method was used to synthesize the spinel nanoparticles. X-ray diffraction, scanning electron microscope with EDAX, transmission electron microscope, and BET surface area were used to determine the phase composition, microstructure, pores size, particle size, and surface area of the synthesized nanoparticles. The spinel nanoparticle was found to have a nano crystallite size with a cubic crystal system, a particle size ranging from 17.2 to 51.52 nm, mesoporous nature (average pore size = 8.72 nm), and a large surface area (61.75 m2/g). The composition ratio of graphite carbon as a base: TOCP as binder: spinal as ionophore was 67.3:30.0:2.7 (wt%) based on potentiometric detections over concentrations from 5.0 × 10−8 to 1.0 × 10−2 mol L−1 with LOD of 5.0 × 10−8 mol L−1. A measurement of 29.22 ± 0.12 mV decade−1 over pH 2.0–7.0 was made for the Nernstian slope. This sensor demonstrated good repeatability over nine weeks and a rapid response of 8 s. A good selectivity was shown for Ni(II) ions across many interferents, tri-, di-, and monovalent cations. The Ni(II) content in spiked real samples, including cocaine, sweets, coca, chocolate, carbonated drinks, cereals, and packages, were measured. The results obtained indicated no significant difference between the proposed potentiometric method and the officially reported ICP method according to the F- and t-test data. In addition to utilizing ANOVA statistical analysis, validation procedures have been implemented, and the results exceed the ICP-MS methodology. [ABSTRACT FROM AUTHOR]

In this study, a comparison is made between the Taguchi and the GRA strategy for enhancing the machinability of AA7178 metal matrix composites that are reinforced with SiC and TiO2 nanoparticles. The composites were produced using a stir casting method, and their machinability was studied using a lathe. The investigation that was carried out with the assistance of a scanning electron microscope (SEM) revealed that the reinforcement particles were dispersed uniformly over the surface of the aluminum matrix. The machining behavior of the composites was extensively investigated using the Taguchi approach and gray relational analysis. The feed had the greatest effect on the surface roughness of AA7178 + 3wt.% SiC(S1) and AA7178 + 3wt.% TiO2(T1) nanocomposites, respectively, as determined by ANOVA. In contrast, the cutting force for S1 and T1 nanocomposite was most affected by the depth of cut and the cutting speed. An examination of the variance of gray relationship grade revealed that cutting speed had a significant effect on both surface roughness and cutting force for S1 and T1, i.e., 59.76% and 71.40%, respectively. Abrasion and built-up edge were the primary causes of tool wear for both materials. [ABSTRACT FROM AUTHOR]

Lithium-doped anatase-TiO2 nanoparticles (LixTi1-xO2 NPs, x = 0, 0.05, 0.10, 0.15 and 0.20) could be synthesized by a simple sol–gel process. X-ray diffraction (XRD) results displayed the tetragonal (space group: I41/amd) of polycrystalline TiO2 anatase phase. The spectroscopy results of Raman and FT-IR confirmed the anatase phase of TiO2 through the specific modes of metal oxides vibration in the crystalline TiO2. Surfaces micrographs by scanning electron microscope (SEM) of agglomerated LixTi1-xO2 NPs showed a spongy like morphology. Transmission electron microscope (TEM) illustrated a cuboidal shape of dispersed NPs with particle size distributed in a narrow range 5–10 nm. Bruanauer Emmett-Teller (BET) results showed the increased surface area of LixTi1−xO2 NPs with increasing Li content. LixTi1-xO2 NPs (x = 0.05–0.20) working electrodes illustrated a pseudocapacitive behavior with excellent electrochemical properties through the whole cycles of GCD test. Interestingly, Li0.1Ti0.9O2 NPs electrode illustrated a high performance in terms of maximum specific capacitance 822 F g−1 at 1.5 A g−1 in 0.5 M Li2SO4 electrolyte, with excellent capacitive retention 92.6% after 5000 cycles GCD test. [ABSTRACT FROM AUTHOR]

A CeO2-doped plasma electrolytic oxidation (PEO) composite coating was prepared on the surface of Cu–Zn alloys by adding CeO2 nanoparticles into the mixed electrolytes of Na2SiO3·9H2O and sodium hydroxide. Surface microstructure and element composition of PEO coatings were studied by a scanning electron microscope (SEM) with energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). Microstructure analysis showed that CeO2 nanoparticles were uniformly deposited on the sample surface, and most of the particles were embedded into PEO coatings. Ce element found in the EDS and XRD analysis confirmed the successful incorporation of CeO2 nanoparticles. Furthermore, with the addition of CeO2 nanoparticles, the coating porosity decreased gradually, while the thickness and surface roughness of PEO coatings decreased and then increased. Corrosion resistance of PEO coatings was investigated by using a potentiodynamic polarization test. The results show that the addition of CeO2 nanoparticles has significantly improved the corrosion resistance of PEO coatings. Especially, the corrosion current density of the PEO coating with 4 g/L CeO2 concentration is 3 orders of magnitude more than that of the bare alloy substrate. [ABSTRACT FROM AUTHOR]

Cocoa pod shells are the byproducts of the cocoa industry. These pod shells were explored for the biogenic synthesis of silver nanoparticles. The synthesized nanoparticles were characterized, and studies were carried out to assess the catalytic and antifungal activities. UV–Vis spectral analysis recorded the surface plasmon resonance at 438 nm. Spherical-shaped particles with a diameter ranging from 48.83 to 55.24 nm were determined by scanning electron microscope. The presence of silver was confirmed through Energy Dispersive X-Ray Analysis. FTIR analysis was carried out to determine the functional groups capped on the surface of the nanoparticles. XRD patterns substantiated the crystalline nature with the sharp peak of 33.16° indicating (101) fcc plane and crystallite size were calculated to be 59.65 nm. Amylase activity was found to be sevenfold higher with a significant amount of 16.05 mg/ml/min in the presence of silver nanoparticles as compared to the control. Methylene blue dye degradation in the presence of silver nanoparticles followed a pseudo-first-order reaction with a degradation constant of 0.1889 min−1 and R2 of 0.9869. In addition, an inhibition activity of 34% against Fusarium oxysporum f. sp. cubense fungi was exhibited by the synthesized silver nanoparticles. The outcome of the investigation has revealed the potential scope of silver nanoparticles as nanocatalysts in starch hydrolysis, dye degradation as well as the antifungal potential. [ABSTRACT FROM AUTHOR]

In this research, the production of cobalt disulfide nanoparticles by hydrothermal and solvothermal methods with new raw materials and solvents has been investigated. Then, nanoparticles were characterized by X-ray diffraction, Energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and Scanning electron microscope. Since the crystalline structure of synthesized nanostructures effectively increases the power of thermal batteries, the effects of such types of reactive salts, the ratio of reactive salts, solvents, and reaction temperature on the production process and its crystalline structure have been investigated. The results showed that changing the type of salts and the molar ratio of salts (1:2 and 2:1), and the type of solvent has no effect on its crystal structure. But, increasing reaction temperature and reaction time leads to an increase in the degree of crystallinity and increasing the size of the particles. In this study, optimum conditions for the synthesis of disulfide cobalt were the salts of cobalt acetate and sodium thiosulfate with ethylene glycol as solvent at 170 °C and 4 h. The amount of material in the reaction temperature was 9.31 g. The synthesized nanoparticles in optimal conditions were in the range of 40–90 nm. [ABSTRACT FROM AUTHOR]

This study focused on investigating the possibility of using different ratios (5, 10, 15 mass%) of recycled alum sludge (RAS) as partial replacement of ordinary Portland cement (OPC), to contribute to solving the problems encountered by cement production as well as stockpiling of large quantities of water-treated sludge waste. MnFe2O4 spinel nanoparticles (NMFs) were used to elaborate the mechanical characteristics and durability of different OPC-RAS blends. The outcomes of compressive strength, bulk density, water absorption, and stability against firing tests fastened the suitability of utilization of RAS waste for replacing OPC (maximum limit 10%). The inclusion of different doses of NMFs nanoparticles (0.5, 1 and 2 mass %) within OPC–RAS pastes, motivates the configuration of hardened nanocomposites with improved physico-mechanical characteristics and stability against firing. Composite made from 90% OPC–10% RAS–0.5% NMFs presented the best characteristics and consider the optimal choice for general construction applications. Thermogravimetric analysis (TGA/DTG), X-ray diffraction analysis (XRD), and scanning electron microscope (SEM) techniques. affirmed the positive impact of NMFs particles, as they demonstrated the formation of enormous phases as ilvaite (CFSH), calcium silicate hydrates (CSHs), MnCSH, Nchwaningite [Mn2 SiO3(OH)2 H2O], [(Mn, Ca) Mn4O9⋅3H2O], calcium aluminosilicate hydrates (CASH), Glaucochroite [(Ca, Mn)2SiO4, and calcium ferrite hydrate (CFH). These hydrates boosted the robustness and degradation resistance of the hardened nanocomposites upon firing. [ABSTRACT FROM AUTHOR]

Zn-doped CuFe2O4 nanoparticles (NPs) were eco-friendly synthesized using plant extract. These nanoparticles were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy and thermal gravimetric analysis (TGA). SEM image showed spherical NPs with size range less than 30 nm. In the EDS diagram, the elements of zinc, copper, iron, and oxygen are shown. The cytotoxicity and anticancer properties of Zn-doped CuFe2O4 NPs were evaluated on macrophage normal cells and A549 lung cancer cells. The cytotoxic effects of Zn-doped CuFe2O4 and CuFe2O4 NPs on A549 cancer cell lines were analyzed. The Zn-doped CuFe2O4 and CuFe2O4 NPs demonstrated IC50 values 95.8 and 278.4 µg/mL on A549 cancer cell, respectively. Additionally, Zn-doped CuFe2O4 and CuFe2O4 NPs had IC80 values of 8.31 and 16.1 µg/mL on A549 cancer cell, respectively. Notably, doping Zn on CuFe2O4 NPs displayed better cytotoxic effects on A549 cancer cells compared with the CuFe2O4 NPs alone. Also spinel nanocrystals of Zn-doped CuFe2O4 (~ 13 nm) had a minimum toxicity (CC50 = 136.6 µg/mL) on macrophages J774 Cell Line. [ABSTRACT FROM AUTHOR]

ZnO nanoparticles show great potential for photodegradation applications due to their excellent physical and chemical properties. Finding a greener approach to producing nanoparticles is of the utmost importance for multidimensional application purposes. In the present study, the ZnO nanoparticles were synthesized by a simple combustion method at 400 °C, using jackfruit extract. X-ray diffraction (XRD) pattern revealed a crystalline structure of the nanoparticles. Scanning electron microscope (SEM), Raman spectroscopy, BET surface area were used to further characterize the synthesized nanoparticles. Further, it has been used as a photocatalyst for the degradation of one of the organic pollutant methylene blue dye. In general, the method employed here is a greener approach to synthesize ZnO nanoparticles with good photocatalytic activity. [ABSTRACT FROM AUTHOR]

This work focuses on the electrochemical synthesis of polymer-inorganic semiconductor hybrid consisting of poly(3-hexylthiophene) (P3HT) and titania nanoparticles (TiO2). The P3HT–TiO2 hybrid was prepared by electropolymerization of the 3HT monomer in a dichloromethane-tetrabutylammonium perchlorate (CH2Cl2/TBAP) solution containing titania nanoparticles (TiO2). The hybrid material was electrodeposited on indium-tin oxide (ITO) substrates via cyclic voltammetry method. It was illustrated from scanning electron microscope observation that the incorporation of TiO2 nanoparticle within P3HT matrix created an interconnected network structure, which has improved interfacial transport charges. Furthermore, the potentiodynamic results revealed that the electropolymerization process of P3HT in the presence of TiO2 was easier and occurred at an early value of 1 V (vs. Ag/AgCl) with a noticeable increase in current density. The impedance results showed lower charge-transfer resistance and higher capacitance values for the P3HT–TiO2 hybrid (Rct = 7 Ω cm−2, CPE = 5.196 μF cm–2) compared to pure P3HT (Rct = 37 Ω cm−2, CPE = 1.959 μF cm–2), demonstrating the better conductivity and charge storage capacity for the P3HT–TiO2 hybrid. [ABSTRACT FROM AUTHOR]

The synthesis of undoped barium oxide (BaO) and neodymium (Nd)-doped BaO nanoparticles (NPs) was carried out through the co-precipitation technique. The synthesis of cubic structure BaO NPs was confirmed through X-ray diffraction (XRD). The crystallite sizes calculated from X-rays diffractometric (XRD) results for undoped BaO and Nd-doped BaO were 10.50 nm and 10.04 nm, respectively. The morphological study and percent composition of synthesized NPs were investigated using a scanning electron microscope and energy-dispersive X-ray analysis. Thermogravimetric analysis confirmed the decomposition of precursor to BaO after annealing at ~ 500 °C. The band gap energy calculated for undoped BaO was 3.7 eV. The substitution of Nd to BaO decreased this value to 3.4 eV. The activation energy calculated for the doped BaO and undoped BaO was 16.5 kJ/mol and 22.5 kJ/mol, respectively. The Nd-doped BaO degraded about 96.4% dye, while the undoped BaO NPs degraded about 86.6% dye within 120 min. The synthesized BaO NPs were used as novel catalysts for the photodegradation of malachite green (MG) dye by varying irradiation time, catalyst dose, pH, temperatures and dye initial concentration. The maximum degradation efficiency was achieved at pH 4, catalyst dose 10 mg, dye initial concentration 50 ppm, and at a temperature of 50 °C. The dye degradation was also studied using the recovered catalysts. [ABSTRACT FROM AUTHOR]

Undoped and Sr-doped CdO nanoplatelets were efficiently synthesized via simple co-precipitation method. The prepared materials were characterized using X-ray diffraction (XRD) and Scanning electron microscope (SEM). XRD pattern confirms the synthesized nanomaterial was phase pure Sr-doped CdO. SEM images reveal the formation of nanoplatelets like morphology. Electrochemical supercapacitor characterization of CdO and Sr-doped CdO nanoplatelets were done using cyclic voltammetry, Galvanostatic charge–discharge, and Electrochemical impedance spectroscopy measurements. The estimated specific capacitance value for Sr-doped CdO and CdO at a current density of 1 Ag−1 was 752 and 250 Fg−1. The Sr-doped CdO nanoplatelets exhibits about three times higher specific capacitance than the pure CdO electrode material. Sr-doped CdO electrode retains 93% of initial specific capacitance after 2000 charge–discharge cycles whereas CdO retains only 85%. The solution resistance (Rs) value of Sr-doped CdO (2.95 Ω) is lower than the CdO (3.57 Ω). This high specific capacitance, long cycle life and low charge transfer resistance confirms the suitability of Sr-doped CdO nanoplatelets for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Nano-lubricants offer improved tribological properties in many applications, such as machines and engines. The presence of nanoparticles in the lubricating oil affects its wear, friction, thermal, chemical and physical properties in many ways. Titanium dioxide (TiO2) is a promising lubricant additive for enhanced engine efficiency. This article reports the effect of 10 W-30 pure base engine oil suspended TiO2 nanoparticles. Four different volume concentrations (0.01%, 0.025%, 0.050% and 0.075%) of TiO2 nanoparticles in the base lubricating oil are used for the analysis. The tribological tests were performed at ambient temperature as well as at 75 °C using a four ball tribometer. Scanning electron microscope (SEM) and Alicona Inginite Focus G5 microscope were used to analyze the worn surface. The results show that the surface-modified TiO2 nanoparticles can remarkably improve the load-carrying capacity, the friction reducing, and anti-wear abilities of the additive oil. The diameter of the wear trace and the coefficient of friction are the tribological properties analyzed for the nano-lubricant prepared at different volume concentration (VC). It was found that the diameter of the wear scar and the coefficient of friction increase with increasing VC of TiO2 nanoparticles in the lubricating oil. The main objective of the paper is to present the recent progress and, consequently, to develop a comprehensive understanding of the tribological behavior of engine oil mixed with TiO2 nanoparticles. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the efficacy of magnetic nanocomposite of cefotax against MRSA. A total of 190 samples were collected from milk, farm personnel and different environmental components from the dairy farm under the study to isolate S. aureus. Cefotax based magnetic nanoparticles was synthetized by the adsorption method and marked using Fourier-transform infrared spectrum (FT-IR), and X-ray diffraction (XRD), then it was characterized using Scanning and Transmission Electron Microscope (SEM and TEM). The obtained results revealed that number of positive samples of S. aureus isolation were 63 (33.1%), mainly from feed manger followed by milk machine swabs (60.0 and 53.3%, respectively) at X2 = 48.83 and P < 0.001. Obtained isolates were identified biochemically and by using molecular assays (PCR), also mec A gene responsible for resistance to cefotax was detected. Testing the sensitivity of 63 isolates of S. aureus showed variable degree of resistance to different tested antibiotics and significant sensitivity to cefotax based magnetic nanoparticles at P < 0.05. It was concluded that dairy environment might act a potential source for transmission of MRSA between human and animal populations. In addition, cefotax based magnetic nanoparticles verified an extreme antimicrobial efficacy against MRSA. [ABSTRACT FROM AUTHOR]

Sn1−xLaxO2 nanoparticles (x = 0, 0.001, 0.01 and 0.1) were prepared using a polyol method. X-ray diffraction patterns showed that only the tetragonal rutile phase is present for x = 0, 0.001, and 0.01. For Sn0.9La0.1O2, in addition to the tetragonal phase, a SnO impurity phase is present for x = 0.1. Fourier transform infrared spectroscopy (FTIR) measurements spotted the variation of local defects and grain size of the prepared nanoparticles. Scanning electron microscope (SEM) images revealed no variation in the microstructure of SnO2 with La doping except for x = 0.1. Ultraviolet–visible absorbance spectroscopy (UV–vis) was utilized to investigate the optical properties and the evolution of the band gap with lanthanum doping. A Brunauer-Emmett-Teller (BET) specific surface area (SSA) method was performed to determine the surface properties of the prepared samples. Vibrating-sample magnetometer (VSM) measurements revealed room temperature ferromagnetism in all the prepared samples. The electron spin resonance (ESR) response shows a clear dependence on La doping. Deep analysis of VSM and ESR results was performed in the frame of the bound magnetic polaron model to understand the origin of room temperature ferromagnetism in these compounds. [ABSTRACT FROM AUTHOR]

This research deals with structural, optical, electrical, and magnetic properties of nanocomposite composed of polymethyl methacrylate (PMMA) and cobalt ferrite (CFO) nanoparticles. Nanocomposite films were synthesized using solution casting technique. The synthesized nanocomposites were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), and high-resolution scanning electron microscope (SEM). Using UV–Vis technique, the absorption coefficient and optical energy gap of the nanocomposite films were determined. The refractive index was calculated using Dimitrov–Sakka relationship. The findings showed that the optical energy gap decreased, and the refractive index increased as the concentration of cobalt ferrite nanoparticles within PMMA matrix increased. The magnetic hysteresis loop of cobalt ferrite nanoparticles and all nanocomposite films show a ferrimagnetic behavior. Dielectric constant, dielectric loss, and the electrical conductivity for all samples increased by increasing the concentration of cobalt ferrite nanoparticles. The values of activation energy decreased by increasing the magnetite nanoparticles content. All the nanocomposite films possess low dielectric loss inferred the potential application in energy storage and embedded electronic devices. [ABSTRACT FROM AUTHOR]

Green synthesis of zinc oxide nanoparticles (ZnO NPs) through simple, rapid, eco-friendly and an economical method with a new haloalkaliphilic bacterial strain (Alkalibacillus sp. W7) was investigated. Response surface methodology (RSM) based on Box-Behnken design (BP) was used to optimize the process parameters (ZnSO4.7H2O concentration, temperature, and pH) affecting the size of Alkalibacillus-ZnO NPs (Alk-ZnO NPs). The synthesized nanoparticles were characterized using UV–visible spectrum, X-ray diffraction (XRD), Scanning electron microscope-energy dispersive X-ray spectroscopy (SEM–EDX), Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and Zeta potential. The UV–Vis spectrum of ZnO NPs revealed a characteristic surface plasmon resonance (SPR) peak at 310 nm. XRD pattern confirmed the hexagonal wurtzite structure of highly pure with a crystallite size 19.5 nm. TEM proved the quasi-spherical shape nanoparticles of size ranging from 1 to 30 nm. SEM–EDX showed spherical shaped and displayed a maximum elemental distribution of zinc and oxygen. FTIR provided an evidence that the biofunctional groups of metabolites in Alkalibacillus sp.W7 supernatant acted as viable reducing, capping and stabilizing agents. [ABSTRACT FROM AUTHOR]

The synthesis of magnetic nano-sized spinel ferrites has become an important area of research, due to their several potential applications. In this work, CoFe2O4 nanoparticles were synthesized by the co-precipitation method. Structural, magnetic, and photocatalytic properties of cobalt ferrites were analyzed based on their chemical composition considering their biological properties. Structural and morphological properties were investigated by X-ray diffraction analysis (XRD) and scanning electron microscope (SEM), respectively. Lattice parameters and cell volumes were calculated from XRD data. SEM images revealed uniform surface morphology and spherical shape of nanoparticles. Magnetization measurements were measured by using Lake Shore 7304 model Vibrating Sample Magnetometer (VSM). In hemolytic activity tests, formation of a precipitate with a characteristic black color provided an explicit evidence to the formation of heme–iron complexes. Undesirable hemolytic effect of CoFe2O4 nanoparticles on human erythrocytes at both concentrations was attributed to the comparatively high amount of reactive oxygen species formed by CoFe2O4 nanoparticles. The theoretical concentration Co (theory) obtained by second-order model (0.82 mg/L) fit with the experimental value of Co (experimental) (0.95 mg/L) well in photocatalytic activity tests. [ABSTRACT FROM AUTHOR]

In the design and synthesis of novel functional materials, a few important challenges that have to be addressed by the material research community are (1) developing robust, reproducible, and environmentally friendly green methods for the synthesis of various nanomaterials and (2) exploring new functional nanomaterials to combat with multi-drug-resistant pathogens. This paper addresses the above-mentioned challenges by (1) demonstrating a green synthesis for the CuO nanoparticles using environmentally benign biosurfactant rhamnolipid (RL) and (2) exploring the antimicrobial activity of RL functionalized/capped CuO nanoparticles (RL-CuO NPs) against various bacterial and fungal species. CuO nanoparticles (CuO NPs) were synthesized using RL by hydrothermal method at pH 9–10. Capping of RL on CuO NPs was probed by characterizing the sample with Fourier-Transform Infrared Spectroscopy (FT-IR) and Thermo Gravimetric Analysis (TGA). Whereas X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) were used to understand the phase, crystallinity, and morphology of CuO NPs. The antimicrobial activity of RL-CuO NPs was examined using resazurin microtitre assay, against Gram-positive bacteria, such as Streptococcus mutans, Staphylococcus aureus, Enterococcus faecalis, for which the minimum inhibition concentration (MIC) values were observed at low concentrations, i.e., 7.8 µg/L of RL-CuO NPs. For Gram-negative bacteria viz. Shigella dysentriae and Salmonella typhi (except Pseudomonas aeruginosa) MIC values were observed at little higher concentrations of RL-CuO NPs, i.e., 250 µg/L. Anti-fungal activity of RL-CuO NPs was examined against Candida albicans, Aspergillus niger and MIC values for these fungi are observed at 125 µg/L and 62.5 µg/L, respectively. [ABSTRACT FROM AUTHOR]

Periodic mesoporous organosilica (PMO) are well known as highly potential materials in biomedical applications. In this work, biodegradable PMO nanoparticles, named E4S, which was incorporated of redox-responsive tetrasulfide bonds, were successfully synthesized with particle size smaller than 50 nm. We study the effect of synthetic conditions, especially the amounts of an alkaline catalyst on particle size and porosity of the nanomaterial. X-ray photoelectron spectroscopy, scanning electron microscope, N2 isotherm sorption, Fourier transform infrared (FT-IR) and thermogravimetric analysis techniques were applied to define structural characteristics. Curcumin, a highly hydrophobic, bioactive natural product, was chosen for loading onto the porous structure of E4S. The material exhibited high efficiency for curcumin loading with the capacity up to 1984 mg g−1. According to the loading investigation of the nanoparticles with various sizes, it is noted that the smallest particle shows the highest curcumin loading capacity which may result from small particle sizes and high specific surface area. These results suggest that ethane-tetrasulfide BPMO could be used as an excellent nanomaterial for curcumin loading. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO NPs) have anticancer, antidiabetic, antibacterial, and anti-inflammatory properties in the biotechnology field. Cafestol, which is the one of the diterpene in coffee, has antimicrobial and anticancer activities. This study aimed to synthesize the cafestol–chitosan–ZnO NP system to evaluate its antibacterial activity. ZnO NPs were produced by the chemical precipitation method. Optimization studies were performed to obtain the desired size of the ZnO NPs. The type of zinc salt [ZnCl2, Zn(SO4)], salt concentration (0.1; 0.2; 0.5 M), base type (NH3, NaOH), reaction time (6, 12, 18, 24 h), mixing speed (300, 400, 500 rpm), and calcination time (1, 2, 3 h) parameters in the method were investigated to yield the targeted size. The optimum experimental conditions required to synthesize in the 45–60 nm size range were determined as a 0.2 M Zn(SO4) salt type and concentration, NaOH base type, 18 h reaction time, at 400 rpm mixing speed and 2 h calcination time. After synthesizing the ZnO NPs coated with chitosan (CS), the cafestol was ligated to the CS–ZnO NP. It was proved by Fourier-transform infrared, differential scanning calorimeter/thermogravimetry analysis/diamond thermogravimetry analysis and scanning electron microscope analyses that cafestol–CS–ZnO NPs were successfully synthesized. The antibacterial effects of cafestol, CS, ZnO NPs, CS–ZnO NPs and cafestol–CS–ZnO NPs were evaluated on human pathogenic Gram-positive strains Staphylococcus aureus ATCC 25923 and Bacillus cereus ATCC 11778 and Gram-negative strains Pseudomonas aeruginosa PA01and Escherichia coli ATCC 25922. The ZnO NPs, CS–ZnO NP, and cafestol–CS–ZnO NP (varying between 20 and 1000 μg/mL) completely inhibited bacterial growth for S. aureus, B. cereus, and E. coli. The incorporation of CS and CS–cafestol improved the antibacterial activity of the ZnO NPs samples against P. aeruginosa PA01 with a 75–87.5% inhibition. The obtained data shows that CS–ZnO and cafestol–CS–ZnO NPs have great potential for biological and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

The chemical co-precipitation route was opted for the synthesis of chromium ferrite (CrFe2O4) nanoparticles and the pristine multi-walled carbon nanotubes (MWCNTs) were used for the preparation of desired CrFe2O4/(MWCNTs)x; x = 0, 5, 10, 15, and 20 wt% nanohybrids using the ultra-sonication method. Toluene was used for the first time as dispersive medium for the preparation of these nanohybrids. The crystalline structure, morphology, vibrational modes, and electrochemical performance of these nanohybrids were characterized by using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry. The structural properties of pristine MWCNTs, CrFe2O4 nanoparticles, and CrFe2O4/(MWCNTs)x nanohybrids are evaluated by XRD and Raman spectroscopy. The SEM images presented the attachment of CrFe2O4 nanoparticles on the surface of MWCNTs. The specific capacitance was decreased with increasing number of cycles, while it was observed to be increased with increasing MWCNTs content. From EIS, the decrease in charge transfer resistance was observed with the increased loadings of MWCNTs, which showed the enhanced electrochemical behavior of these nanohybrids. Therefore, the significant improvement in electrochemical properties showed that these nanohybrids can be promising candidates for energy storage devices like lithium-ion (Li-ion) batteries. [ABSTRACT FROM AUTHOR]

In order to satisfy the requirement of lubrication under extreme working conditions (e.g., heavy load, high speed, and high temperature), a lubricating grease containing boron nitride (BN) nanoparticles was prepared by ultrasonic dispersion. And the effect of different content of nanoboron nitride on the tribological properties of lubricating grease was studied by means of a four-ball friction tester. The results showed that the grease containing 0.60 wt.% BN nanoparticles had the best anti-friction performance, as well as the smallest friction coefficient and wear scar radius. Additionally, a Raman spectrometer, scanning electron microscope, and three-dimensional profilometer were used to analyze the chemical composition, characterize the morphology of the wear scar in the steel balls after the friction tests, and the analysis results show that BN nanoparticles can not only produce lubricating film to protect friction pairs, but also its layered structure is easy to cause sliding of the friction pairs under the action of friction. Therefore, under the synergism of lubricating film and layered structure, the friction coefficient is obviously reduced and the friction reduction performance of grease is improved. [ABSTRACT FROM AUTHOR]

To study the modification effect and mechanism of porous nanoparticles on electrical insulation performance, SiO2/low-density polyethylene (LDPE) nanocomposites with different filler concentrations are prepared by filling two kinds of porous SiO2 nanoparticles. The microstructure and dispersion of SiO2 in LDPE are characterized by scanning electron microscope [ the effect of nanofilling on the crystallinity of LDPE is analyzed by Differential Scanning Calorimetry (DSC)]. The mechanism of insulation modification of nanocomposites is studied by space charge and direct current conductance analysis of charge transport and Weibull distribution of breakdown field strength. By filling nanoscale SiO2 particles, the crystallinity of the LDPE matrix can be changed effectively. It is indicated that the hydrophobic SiO2 nanofillers with higher dispersity in LDPE matrix are more effective than hydrophilic SiO2 nanofillers to improve the crystallinity of LDPE matrix. The LDPE crystallinity of hydrophobic 1 wt% SiO2/LDPE nanocomposite approaches the highest value through heterogeneous nucleation. Compared with pure polyethylene, the conductivity of nanoporous SiO2 filled polyethylene composites is reduced obviously and the lowest conductivity is obtained for the nanocomposites filled with hydrophobic SiO2 nanoparticles in 1 wt% filling rate. The space-charge distribution and electric breakdown field strength further demonstrate that the filling of 1 wt% hydrophobic SiO2 nanoparticles can efficiently inhibit carrier injection and increase the breakdown field strength. The heterogeneous nucleation of porous SiO2 nanofillers increases the crystallinity of LDPE, and thus decreases the carrier mobility and increases the probability of charge charge trapping. The dispersion of nanofillers in composite is improved significantly by the symmetrical group –CH3 on the surface of hydrophobic SiO2 nanoparticles, which effectively suppresses the space-charge accumulation and evidently increases the electric breakdown field strength. It is proved that the special nanoscale interface in nanodielectrics can substantially improve the dielectric properties of polyethylene. [ABSTRACT FROM AUTHOR]

Epoxy-based adhesives are widely used for repairing or jointing the metal sheets in the industry. Because of their superior mechanical properties, the metallic nanoparticles can be selected as the additive of the epoxy adhesive. The strength of the Cu nanoparticles (CuNPs) can be expected to improve the mechanical properties of neat epoxy. In this study, CuNPs were added at various weight ratios, such as 1, 2, 5, 10, 15, and 20% into the epoxy resin adhesive. Tensile tests of the dog-bone specimens and the lap-shear tensile tests of the single lap joints were performed for obtaining the mechanical properties. In order to investigate the failure mechanisms, the fractured surfaces of the tensile test samples and adhesively joined sheets were imaged by using a Scanning Electron Microscope. The thermal properties of the adhesives were obtained by using Thermo Gravimetric Analysis and Differential Thermal Analysis. The mechanical and thermal properties of epoxy resin adhesive were improved by adding the CuNPs. The best adding ratios of CuNPs into epoxy were obtained by both mechanical and thermally point of views. As a result of this study, 15 wt% the ratio of Cu nanoparticle adding into the epoxy-based adhesive is suitable for improving the mechanical properties. On the other hand, 20% is the proper Cu nanoparticle adding ratio for the thermal properties improving. [ABSTRACT FROM AUTHOR]

Over the past decade, electrochemical devices have significantly improved due to advanced fabrication and synthesis of nano-electrode materials. However, the cost-effective and -efficient fabrication of nanomaterials is still challengeable. In this regard, we have used bio-organic compounds of E. cognata as fuel to synthesize and functionalize the Co3O4 nanoparticles and then incorporated NiO–PdO–Pd following the hydrothermal route. X-ray diffraction revealed Co3O4:NiO–PdO–Pd phases with crystallite size of 21 nm while spherical-shaped nanoparticles are observed by scanning electron microscope. The X-ray photoelectron spectroscopy revealed the presences of organic-functional groups of E. cognata on the surface of synthesized nanomaterial. The as-synthesized Co3O4:NiO–PdO–Pd nanomaterial is investigated as supercapacitor electrode material. In 3 M KOH the Co3O4:NiO–PdO–Pd nanomaterial exhibits a specific capacitance of 217.4 F/g. The Co3O4:NiO–PdO–Pd was reach up to 142.91 F/g at 10 mV/s while 115.15 F/g of capacitance is achieved by GCD data. Moreover, excellent conductivity is revealed by lower internal Ohmic resistance of 0.71 Ω which corresponds to the efficient transport of charges, and promotes the electrolyte diffusion. These results indicate that Co3O4:NiO–PdO–Pd nanomaterial can be a potential electrode for supercapacitor application. [ABSTRACT FROM AUTHOR]

In this research study, the effect of zirconia nanoparticles on the biological properties of the hydroxyapatite (HA) scaffolds was evaluated. The zirconia nanoparticles with various weight percentages of 5, 10, and 20 were mixed with hydroxyapatite powder using a ball-milling process. Then, they were cold pressed and heat-treated at 1150 °C. Scanning electron microscope and x-ray diffraction analysis were used to evaluate the morphology and phase analysis of the samples, respectively. The results of the microstructure and phase analysis revealed that some zirconia nanoparticles reacted with the HA during the sintering process, which besides the formation of the tertiary calcium phosphate and calcium zirconium phases, it resulted in creating some microporosities in the scaffold. The biological behavior of the samples was investigated by osteoblast-like cells. The results of the biological assessment demonstrated that the presence of the zirconia nanoparticles in the HA scaffold improved the biological behavior (cell attachment and cell proliferation). The HA specimen composed with 10 wt.% zirconia nanoparticles showed the highest bioactivity. In addition, the compressive strength of the HA sample composed of 10 wt.% zirconia nanoparticles was improved by 30%. [ABSTRACT FROM AUTHOR]

Inorganic semiconducting ZnS doped with Cr nanoparticles was fabricated using chemical co-precipitation method with monothioethylene glycol as capping agent. This study is an effort to investigate as to how various concentration ratios of systematically doped Cr (1, 3, 5, and 7 wt%) to ZnS affect structural, optical, and morphological properties at room temperature. Powder X-ray diffraction (XRD) studies revealed that crystallinity improved upon doping and the synthesized material has cubic structure without secondary phase. XRD and Raman spectra showed successful incorporation of Cr3+ particles into ZnS host lattice. The functional groups and chemical species associated with vibration of molecules were determined with Fourier transform infrared spectroscopy (FTIR). Field-emission scanning electron microscope (FE-SEM) and high-resolution transmission electron microscope (HR-TEM) images showed nanoscale particles with cubic and spherical morphology. Elemental composition of Cr-ZnS particles was determined using energy-dispersive X-ray (EDX) spectroscopy. Kinetics of degradation of methylene blue (MB) catalyzed via synthesized nanoparticles was recorded under UV–Vis irradiation. The antimicrobial evaluation of Cr-doped ZnS nanocomposites against MDR S. aureus showed significant (p < 0.05) inhibition zones compared to undoped ZnS. The catalytic activity results indicate that ZnS is an efficient nanocatalyst that could be effectively used for the removal of environmental pollutants. [ABSTRACT FROM AUTHOR]

Iron and cobalt hexacyanoferrates and their analogs (MHCF) have been synthesized as nanomaterials for the fabrication of C/MHCF composite electrodes. We have studied the structural characteristics and elemental composition of the synthesized compounds by X-ray diffraction and energy dispersive X-ray microanalysis using a VEGA II LMU scanning electron microscope equipped with an INCA Energy 450/XT X-ray microanalysis system (X-Act DDD detector). The results demonstrate that the composite electrodes containing 20% MHCF have a better electrochemical performance than does a carbon electrode. The incorporation of sodium into the structure of iron and cobalt hexacyanoferrates ensures the smallest decrease in the specific capacitance of the composite electrodes at high charge–discharge rates and reduces the charge transport resistance. [ABSTRACT FROM AUTHOR]

Undoped and In3+ doped β–Ga2O3 nanoparticles have been synthesized at 900 °C using polyol-mediated technique. The effect of Indium dopant on structural, morphological and photoluminescence properties of β–Ga2O3 nanoparticles were investigated in detail. X-ray diffraction patterns demonstrate the monoclinic crystalline structure and indium doping leads to substantial changes in the lattice parameters of β–Ga2O3 nanoparticles. The scanning electron microscope (SEM) images showed reduction in the particle size on doping as due to grain growth inhibition effect. Observed red shift in emission maxima and is increasing with increased In3+ content. Indeed, the shift changes are due to the interactions between donors and acceptors, which are identified as donor–acceptor pair recombination. To understand the red-shift phenomena, we performed time-resolved and steady-state spectroscopic studies for the doped samples. The red shift in the emission maxima of Indium-doped samples was further confirmed with the band gap measurements using absorption spectroscopy and ab initio calculation results. [ABSTRACT FROM AUTHOR]

An electrochemical discharge machining process to produce zinc oxide (ZnO) nanoparticles (NPs) under varying voltage and duty factors has been investigated. The morphological and optical characterizations of the generated ZnO NPs were carried out. It was observed that the production rate of NPs and their size increased with an increase in voltage. The ZnO NPs produced at 120 V showed the maximum production rate larger NPs. The field-effect scanning electron microscope images of the NPs revealed a nanorod-like structure, large conical shape rods and hexagonal wurtzite-like structures. The ZnO NPs generated at 120 V and 20% duty factor presented less agglomeration of NPs compared to other NPs generated by varying electrical parameters. The crystal size of the ZnO NPs were found to vary from 31.08 nm to 50.37 nm. The ZnO NPs were also tested for use in a supercapacitor electrode, and the results showed that the specific capacitance of the electrode was 708.75 F/g at a current density of 1 A/g and a retained capacity of 90.42%. [ABSTRACT FROM AUTHOR]

The present study reports the effective synthesis of zinc oxide nanoparticles (ZnO Nps) by microwave irradiation method using Indian bael (Aegle marmelos) juice as fuel. The synthesized nanostructures were characterized by X-ray diffraction, FT-IR, scanning electron microscope, transmission electron microscope, Raman Spectroscopy, photoluminescence and ultraviolet (UV)–visible studies. At room temperature, photoluminescence spectrum showed the excitation wavelength at 370 nm and emission peaks at 388 and 468 nm corresponding to Zn vacancies and O vacancies, respectively. Further, the effectiveness of the synthesized zinc oxide nanoparticles was tested for methylene blue dye degradation under UV irradiation. The dye removal efficiency of nanoparticles was 96% after 35 min of UV (λ = 617 nm) irradiation. The ZnO nanoparticles were subjected to antimicrobial activity against different strains. The current synthetic work pledges to provide some new visions into the design of nanomaterial for multifunctional long-term applications for cleanup and biomedical applications. [ABSTRACT FROM AUTHOR]

ZrO2·Al2O3:Er powder was synthesized by the conventional solid-state reaction method. All the synthesized materials were monoclinic structure of ZrO2 (m-ZrO2) and Al2O3 phases. Scanning electron microscope images showed the spherical particles with diameter of ∼ (30–200) nm. The down-conversion luminescence spectra excited by 380 nm shows near infrared emission band is centered at 1540 nm, corresponding to the transitions of 4I13/2–4I15/2 of Er3+ ions. Under the excitation of a 976 nm laser diode, the up-conversion luminescence spectra of the samples show a red emission band at ∼ 680 nm and a green emission band at ∼ 565 nm, corresponding to the transitions of 4F9/2–4I15/2, 4S3/2–4I15/2, of Er3+ ions, respectively. The dependence of up and down-conversion luminescence properties on dopant concentrations, annealing temperature and Al2O3 concentrations are investigated. These results suggested that this phosphor is a very promising material for light emission and bioimaging. [ABSTRACT FROM AUTHOR]

This paper reports a facile strategy for one-step synthesis of graphene anchored with super-tiny (< 5 nm) nickel nanoparticles (graphene@Ni) with high perfomance microwave absorption. The phase structure, morphology and magnetism of graphene@Ni were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM), respectively. The magnetic Ni nanoparticles with 2.45 nm in average size are densely anchored on the surface of graphene. The electromagnetic characteristics of graphene@Ni compounds were measured by vector network analyzer using a coaxial line method in the frequency range of 1–18 GHz. The reflection loss (RL) of graphene@Ni reaches − 53.92 dB at 9.5 GHz with a thickness of 2.8 mm, and the maximum effective absorption bandwidth with RL values lower than − 10 dB is 5.44 GHz covering from 11.45 to 16.89 GHz at a thickness of 2.1 mm, showing that both of the RLmin and absorption bandwidth for graphene@Ni are obviously enhanced with thinner thickness compared to pure Ni NPs and graphenes. The real RL of graphene@Ni modified aramid fabrics/bismaleimide composite laminate is also measured for comparison, which is basically consistent with simulated results of graphene@Ni. Therefore, the graphene@Ni compounds have advantage in practice for high performance microwave absorption applications. [ABSTRACT FROM AUTHOR]

ZnAl2O4 nanoparticles (NPs) doped with Cr3+ (1.0 mol%) were prepared by citric acid assisted sol–gel method at pH values of 3, 5, 7, 9, 11 and 13 with the use of ammonia as pH controller. Analysis of x-ray diffraction (XRD) spectra show that the synthesized ZnAl2O4 NPs are cubic structured and the pH did not affect the structure significantly. The average crystallite size increases with an increase in pH. The photoluminescence (PL) intensity was found to be minimum and maximum for the sample synthesized at pH 3 and pH 13, respectively. The PL emission intensity was found to depend on the synthesis pH conditions. The scanning electron microscope (SEM) revealed that the morphology of ZnAl2O4:Cr3+ NPs changed with the pH values of the solution. Ultraviolet–visible (UV–Vis) measurements show that reflectance is maximum in UV and visible region for sample synthesized under acidic pH of 5. The energy band gap energy was tuned from 3.10 to 3.88 eV with increase in pH value from 3 to 13. It was observed that a strong alkaline nature of the solution enhances the structural and optical properties of ZnAl2O4:Cr3+ nanostructures. [ABSTRACT FROM AUTHOR]

We investigate the optimal growth conditions for ErAs nanoparticle powders by nanosecond pulsed laser ablation in a He environment from elemental pressed powder targets. Incongruent ablation of the target due to differences in vaporization enthalpies is observed, and compensation for these differences is explored through altering target composition. The preferential ablation of As from the Er-As pressed powder targets appears to diminish over time, resulting in the reduced impact of differing vaporization enthalpies. Additionally, the influence of collection distance is investigated as a means to control crystallite size and powder composition. Particle size is shown to increase with collection distance and appears to reach a plateau as the beaker diameter becomes much larger than the plume size. [ABSTRACT FROM AUTHOR]

In the present work (0-20%) Mn doped NiO, (10-20%) Ni doped Mn3O4, and composite NiO/Mn3O4 nanoparticles were synthesized using the solid state reaction method. The purity of the nanoparticles was confirmed using x-ray diffraction (XRD) study. Scanning electron microscope (SEM) images confirmed the formation of irregularly shaped nanoparticles with an average diameter of 50-100 nm. Then humidity sensors based on these nanoparticles were fabricated and tested. The doping up to certain content enhanced the sensitivity, and the maximum sensitivity of 70% was observed for 10% Ni doped Mn3O4. These sensors exhibited reasonably fast response and recovery times and were better or comparable to those of similar materials. Therefore nickel/manganese oxide nanoparticles are suitable for use in fabrication of humidity sensors. [ABSTRACT FROM AUTHOR]

Mg doped NiO nanoparticles MgxNi1−xO (x = 0, 0.1, 0.2, 0.3, 0.4) have been synthesized using sol–gel method. Their structure and morphology of the sample were analyzed using X-ray diffractometer (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM) with energy dispersive X-ray spectrum (EDX). From the XRD analysis, it is observed that the sample can have FCC structure with a particle size of 22 nm. Functional group analysis was carried out using Fourier transform infrared spectroscopy (FTIR) and Ultraviolet visible spectrometer. The obtained band gap was 4.254 eV. Photoluminescence (PL) emission spectra showed blue emission with a strong band at 345 nm. SEM and TEM images confirmed the spherical morphology and high crystalline nature of the samples. EDX spectrum showed the purity of the samples. The magnetic properties of the samples were analyzed using the vibrating sample magnetometer (VSM). 0.3 %Mg doped samples showed room temperature ferromagnetism with higher saturation magnetization. The synthesized nanoparticles were used further for the fabrication of low cost counter electrode for dye-sensitized solar cells (DSSCs). A thin film of pure and Mg doped NiO nanoparticles deposited on Fluorine tin oxide (FTO) coated glass substrate serves as an efficient plate to increase the number of holes and induced the electrocatalytic activity and yield the efficiency of 2.4%. [ABSTRACT FROM AUTHOR]

Magnetic nanofluids (commonly known as ferrofluids) have captured the great attention of the researchers due to their various kinds of applications such as heat transfer, hyperthermia treatments, targeted drug delivery etc. The present experimental investigations deal with the thermoacoustic behaviour of the water based nanofluids of nickel ferrites. The magnetic nickel ferrite nanoparticles were produced by the simple and inexpensive chemical co-precipitation route. The prepared nanoparticles were exposed to different characterization tools for structural, morphological, compositional and magnetic properties analysis. X-ray diffraction analysis with Rietveld refinement confirmed the single phasic nature with nanometric crystallite size of the prepared nanoparticles. Scanning electron microscope images revealed the spherical and nanocrystalline morphology of the prepared nanoparticles. The M-H plot recorded at room temperature revealed the superparamagnetic nature of the nanoparticles. Further, the co-precipitated nickel ferrite nanoparticles with different concentrations were utilized for the preparation of the water based magnetic nanofluids. Colloidal stability of the prepared nanofluids was analyzed by UV–Vis spectroscopy technique and it revealed the stability over 11 days without separation in phase. The temperature dependent thermoacoustic properties of the prepared nanofluids were analyzed through Ultrasonic Interferometer. The interaction between particle–particle and particle–fluid are explained on the basis of thermo-acoustic parameters. [ABSTRACT FROM AUTHOR]

A series of monodisperse Y2WO6: Dy3+, Gd3+ hierarchical microspheres were synthesized via a facile surfactant-assisted hydrothermal method followed by heat treatment. The as-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and photoluminescence (PL) spectra. XRD patterns of the samples with Gd3+ codoping exhibit a merging of (− 232) and (232) peaks, indicating the distorted deformation in Y2WO6 host structure. SEM images demonstrate that the Y2WO6: Dy3+, Gd3+ microspheres are well-dispersed and assembled by many irregular nanoparticles. Upon ultraviolet (UV) excitation at 291 nm, the emission peaks of Dy3+ ions is observed at 480 nm (blue), 579 nm (yellow) and 669 nm (red), corresponding to the characteristic transitions of 4F9/2 → 6H15/2, 4F9/2 → 6H13/2 and 4F9/2 → 6H11/2 of Dy3+, respectively. The optimal PL intensity was obtained in Y2WO6: 2.5 mol% Dy3+ microspheres which can be further enhanced with the codoping of Gd3+. The strongest luminescence is achieved at Gd3+ concentration of 40 mol% with a quantum yied (QY) of 34.45%. In addition, the thermal stability of the sample was also investigated. The CIE of the investigated samples exhibit little change by varying the concentration of Gd3+ ions. The calculated CIE values are all around (0.37, 0.38) and located at the white region, suggesting that the Y2WO6: Dy3+, Gd3+ microspheres could be used for white LEDs. [ABSTRACT FROM AUTHOR]

Abstract: Nano-functionalization of textiles has been developed for various applications that should be adapted to reduce the utilization of chemicals, energy, processing steps and time of the finishing in view of the ecological and economical restrictions. In the current study, for the first time, we introduce an eco-friendly, feasible and facile approach for producing synthetic or natural fabrics with multi-functional properties via green assembling of copper-based nanoparticles in one single step without the use of further chemicals or external physical apparatuses. Copper acetate was only used as a metal salt with textile substrate as a template at boil without using other chemicals. X-ray diffraction analysis, energy-dispersive X-ray spectroscopy, mapping, field-emission scanning electron microscope images, Fourier transform infrared spectra and UV-Vis spectrum were proved the formation of copper or copper oxide nanoparticles on the textile substrates. The treated fabrics indicated very good properties regarding antibacterial, self-cleaning, photocatalytic, UV protection and coloring effect with enhanced mechanical properties. Finally, this novel method can be applied as a cleaner, economic and large-scale strategy for nano-functionalization of textiles and polymers based on copper/copper oxide nanoparticles in the related industries.Graphical abstract: [ABSTRACT FROM AUTHOR]

The aim of this study was to produce magnesium-based surface nanocomposites via friction stir processing and to investigate the effect of tool rotational speed on the microstructure, hardness and wear behavior. The surface of the nanocomposites was characterized using optical and scanning electron microscopes, as well as through microhardness and wear tests. The results indicated that with the increase in rotational speed, the grain size of the surface nanocomposites increased, but its hardness decreased despite the improved distribution of Al2O3 nanoparticles. It was also found that the wear resistance has a direct relation to the distribution of the Al2O3 nanoparticles. Furthermore, the addition of nano-Al2O3 changed the wear mechanism from the adhesive mode in the as-received AZ31 to the abrasive mode in the nanocomposite specimens. The rotational speed of 1400 rpm was an optimum parameter to achieve a suitable composite layer with the highest wear resistance. [ABSTRACT FROM AUTHOR]

A simple and cost-effective route was used in the synthesis of CuO nanoparticles and it was aided by the chemical precipitation method. From XRD investigations the grain size was determined to be ≈14 nm. FTIR and FT-Raman was used to verify the various functional groups of CuO nanoparticles. Scanning electron microscope (SEM) and EDS spectroscopy was utilized to study the surface morphology and elementary compostion. The particle size of the CuO nanoparticles was estimated using transmission electron microscopy. The SAED pattern of CuO nanaoparticles confirmed it's polycrytalline nature. Random distribution of grains in the CuO nanoparticles was exemplified by the SEM images. UV-Visible absorption spectrum was used to study the optical properties. The optical band gap energy of CuO nanoparticle was evaluated to be 2.85 eV. Detailed investigation and analysis of the dielectric constant, dielectric loss and AC conductivities was performed. Beside simplicity, the results show the reliability and cost efficiency of the aqueous precipitation technique for the development of CuO-NP's that can be utilized for potential application, provided it's loss can be reduced. [ABSTRACT FROM AUTHOR]

The present study report is on synthesis and characterization of cadmium oxide nanoparticles (CdO) which were prepared by the microwave irradiation method. The prepared nanoparticles were characterized by various techniques such as X-ray diffraction, Fourier transforms infrared spectroscopy, scanning electron microscope, energy dispersive spectroscopy, transmission electron microscope, ultraviolet visible diffuse reflectance spectroscopy, and photoluminescence techniques. The CdO nanoparticles are found to be cubic in structure from its XRD pattern. The average particle size was calculated from XRD analysis, which varies from 37 to 19 nm. The nail shaped morphology was confirmed by TEM analysis. Linear optical studies were used to determine the band gap energy of CdO nanoparticles. The DC electrical conductivity studies described the annealed CdO have a maximum conductivity compared to as prepared. The nail shaped CdO nanostructure was coated on the p-Si substrate using jet nebulizer spray pyrolysis technique. The fabricated Ag/n-CdO/p-Si diode parameters were evaluated in darkness and below different light sources such as Halogen and Metal halide lamps. [ABSTRACT FROM AUTHOR]

This work has provided a general, simple, and effective method to control the composition and morphology of CoTiO nanoparticles, which revealed potential new insight into inorganic synthesis methodology. CoTiO nanoparticles were synthesized via a novel route based on the reaction between cobalt salt and tetra-n-butyl titanate (TNBT) in ethanol. Results of this investigation demonstrate that CoTiO with very uniform sphere-like shape, small grain size and pure rhombohedral phase could be synthesized by different capping agents such as asparagine, alanine, and leucine. XRD, SEM, EDS, and UV-vis spectroscopy were employed to characterize structural, morphological, and optical properties of CoTiO nanoparticles. According to the vibrating sample magnetometer (VSM) result, CoTiO nanoparticles indicated a paramagnetic behavior at room temperature. Furthermore, the photocatalytic properties of as synthesized CoTiO were evaluated by degradation of methyl orange (MO) as water contaminant. [ABSTRACT FROM AUTHOR]

The main objective of this study deals with the synthesis and characterization of NiCoFeO (x = 0.3, 0.5, 0.7) by a facile novel co-precipitation method using citrate as chelating agent. TG/DT analysis was performed for the as-prepared sample, which shows the calcination is necessary for the formation of pure nickel cobalt ferrite nanoparticles. The synthesized powders were calcinated at 400, 600 and 800 °C for 3 h in air and were characterized by X-ray diffraction (XRD) which confirmed the formation of cubic spinel structure of ferrites. From XRD it confirms that NiCoFeO nano particles belong to spinel type lattice of space group Fd3m. The linear relationship between particle size and calcination temperatures of NiCoFeO nanoparticles was observed. The NiCoFeO nano particles calcinated at 600 °C were further characterized by using techniques field emission scanning electron microscope (FESEM) with EDAX, field emission transmission electron microscope (FETEM) with SAED pattern, dynamic light scattering zeta potential, X-ray photoelectron spectroscopy and cyclic voltammetry (CV). The surface morphology of NiCoFeO studied through FESEM and FETEM indicate that the particles are found crystalline and are in cubic shape. EDAX analysis revealed the presence of Ni, Co, Fe and O. Zeta potential exposes the good stability of the prepared NiCoFeO nanoparticles. Capacitance value 865 Fg was observed for the scanning rate of 2 mV s from the CV study and concluded it can be used for super capacitor application. [ABSTRACT FROM AUTHOR]

Multiferroic nanoparticles having general formula BiFeMnCuO (x = 0, 0.01, 0.02, 0.03 & 0.04) were prepared by a chemically derived method to explore the magneto-electric characteristics of this new class of materials. X-ray diffraction confirmed that all the samples had rhombohedraly distorted cubic perovskite 3D lattice. Lattice constant was increased with increasing concentration of Mn. Micrographs obtained from a field emission scanning electron microscope revealed a fine distribution of well-shaped particles while the particle size was increased with increased contents of Mn. Enhanced hopping mechanism induced by substitution of Mn at the lattice sites of Fe resulted in an increased AC conductivity. Ferroelectricity was observed to increase with increased Mn, attributed mainly to the leakage current due to free charge carriers instigated by multiple oxidation states of Fe and Mn. It has been observed that antiferromagnetic bismuth ferrite begins to show ferromagnetic behavior due to the collapse of antiferromagnetic spin structure with increased Mn contents. [ABSTRACT FROM AUTHOR]

In this study, cupric oxide (CuO) nanoparticles were synthesized via sonochemical method. The samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, and transmission electron microscopy. The spherical CuO nanoparticles were dispersed in sodium hexametaphosphate under sonication (25 kHz) to analyze the particle size distribution and UV absorption spectra. Using these absorption spectra, we further examined the CuO nanoparticle to explore the possibility of using them as a material for applications such as solar cell and textile production. [ABSTRACT FROM AUTHOR]