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The emergence of antibiotic‐resistant bacterial infections is a principal threat to global health. Functionalization of nanomaterial with antibiotics is known as a useful method for increasing the effectiveness of existing antibiotics. In this study, vancomycin‐functionalized ZnFe2O4 nanocomposite (ZnFe2O4@Cell@APTES@Van) was synthesized, and its functional groups and particle size were characterized using Fourier‐transform infrared spectroscopy, thermogravimetric analysis, dynamic light scattering, scanning electron microscope, and transmission electron microscopy. The antibacteria activity of the synthesized nanocomposite was evaluated using minimum inhibitory concentration and minimum bactericidal concentration against Escherichia coli, Staphylococcus aureus, and methicillin‐resistant Staphylococcus aureus (MRSA). Cytotoxicity assay was done by 2,3‐bis‐(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium‐5‐carboxanilide method. Characterization analyses of synthesized nanocomposite confirmed the binding of vancomysin on the surface of ZnFe2O4@Cell@APTES. Nanocomposite exhibited an aggregated semi‐spherical structure with hydrodynamic radii of ∼382 nm. In vitro antibacterial activity test showed that vancomycin and vancomycin functionalized ZnFe2O4 have no antibacterial effect against E. coli. S. aureus was sensitive to vancomycin and ZnFe2O4@Cell@APTES@Van NPs and ZnFe2O4 NPs did not improve vancomycin antibacterial activity against these bacteria. MRSA is resistant to vancomycin while ZnFe2O4@Cell@APTES@Van NPs was efficient in inhibiting MRSA growth. In summary, this study showed that attachment of vancomycin to ZnFe2O4 NPs was increased its antibacterial activity against MRSA. [ABSTRACT FROM AUTHOR]

To design more environmentally friendly, economical, and efficient demulsifiers for oily wastewater treatment, hydrophobic octadecylphosphonic acid (ODPA)-modified Fe3O4 nanoparticles (referred to as Fe3O4@ODPA) were prepared by condensation of hydroxyl groups between ODPA and Fe3O4 nanoparticles using the co-precipitation method. The prepared magnetite nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric/differential thermogravimetric (TG/DTG) analysis. The water contact angles (θW) of Fe3O4@ODPA nanoparticles were more than 120°, indicating hydrophobic nature, and the diameter of the obtained spherical-shaped magnetite nanoparticles was 12–15 nm. The ODPA coating amount (AO) (coating weight per gram Fe3O4) and specific surface area (SO) of Fe3O4@ODPA were 0.124–0.144 g·g−1 and 78.65–91.01 m2·g−1, respectively. To evaluate the demulsification ability, stability, and reusability, the magnetite nanoparticles were used to demulsify an n-hexane-in-water nanoemulsion. The effects of the magnetite nanoparticle dosage (CS), pH value of nanoemulsion, and NaCl or CaCl2 electrolytes on the demulsification efficiency (RO) were investigated. The RO of Fe3O4@ODPA samples was found to be higher than that of bare Fe3O4 samples (S0, ST, and SN) under all CS values. With the increase in CS, the RO of Fe3O4@ODPA samples initially increased and then approached equilibrium value at Cs = 80.0 g·L−1. A maximum RO of ~93% was achieved at CS = 100.0 g·L−1 for the Fe3O4@ODPA sample S2. The pH and two electrolytes had a minor effect on RO. The Fe3O4@ODPA nanoparticles maintained high RO even after being reused for demulsification 11 times. This indicates that the hydrophobic Fe3O4@ODPA samples can be used as an effective magnetite demulsifer for oil-in-water nanoemulsions. [ABSTRACT FROM AUTHOR]

Eu-doped WO3 (WO3:Eu3+) nanoparticles were prepared by the Pechini method. Tetrabutyl titanate (TBOT) was used to prepare TiO2-encapsulated WO3:Eu3+ nanoparticles (TiO2@WO3:Eu3+). Microstructure and morphology of the prepared nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The results show that the mean diameter of the TiO2@WO3: Eu3+ nano powder prepared at pH = 10 is the smallest, up to 50 nm. The tribological properties of the TiO2@WO3:Eu3+ as extreme pressure and wear resistance agents in water-based lubricant were investigated by a four-ball machine. The results showed that TiO2@WO3:Eu3+ exhibits excellent load-carrying capacity, anti-wear, and anti-friction properties in water-based lubricant, especially when the concentration of TiO2@WO3:Eu3+ was 0.4 wt%. The average wear scar diameter (WSD) was decreased from 0.62 to 0.34 mm and the coefficient of friction (COF) was reduced from 0.0721 to 0.053. This is mainly because of the formation of tens of nanometers thick tribofilm, the actual contact between metals is prevented. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) nanostructures are systems with many fascinating novel properties that can be used to study new science and have significant promise for applications. In this study, graphene oxide was prepared using the modified Hummer's method. In addition, potassium ferrite is a good candidate for biomedical application, as iron and potassium are biocompatible and non-toxic materials. Mg0.85K0.3Fe2O4/GO nanocomposites were prepared by the citrate auto-combustion method. The effect of adding GO to Mg0.85K0.3Fe2O4 on structure, morphology, electrical, and magnetic properties was discussed. Samples under investigation were characterized using XRD, infrared spectroscopy (IR), high-resolution transmission electron microscopy (HRTEM), and atomic force microscopy (AFM). The crystallite size of prepared samples was decreased from 28.098 to18.148 nm by increasing GO content. Scanning electron microscope (SEM) confirms the successful adhesion of Mg0.85K0.3Fe2O4 nanoparticles on graphene oxide sheets, which are dispersed in a metal oxide matrix. EDAX analysis confirms the existence of C, O, K, Mg, and Fe elements present in the samples. Magnetic properties were studied by VSM and Faraday's method. GO has a significant effect on the magnetic properties of nanocomposites. For instance, the saturation magnetization and Curie temperature have diverse values, which will be appropriate for numerous applications. [ABSTRACT FROM AUTHOR]

In the present work, Ni0.6Cd0.4DyxFe2-xO4 (x = 0.0, 0.05, 0.10, 0.15, 0.20) nanoparticles (NPs) were synthesized by using sol–gel method. X-ray diffraction (XRD) patterns confirmed that the pure and dysprosium substituted Ni–Cd ferrites are in single-phase spinel structures, while a trace of DyFeO3 appears as a minor phase for higher concentrations (x = 0.10, 0.15 and 0.20). The Debye–Scherrer's method and Williamson–Hall (W-H) method were used to evaluate the crystallite sizes and lattice strain. Scanning electron microscope (SEM) images show that reduction of grain size with Dy3+ content. Elemental composition features of samples were examined by Energy-dispersive X-ray spectroscopy (EDS). The average particles size estimated from transmission electron microscopy (TEM) analysis is in good agreement with results obtained from XRD. The results showed that saturation magnetization (Ms) decreases and coercivity (Hc) increases with an increase in Dy3+ concentrations. The dielectric constant was found to decrease with increasing Dy content in Ni–Cd ferrites. [ABSTRACT FROM AUTHOR]

Nanostructure morphologies of transition metal dichalcogenides (TMDs) are gaining much interest owing to their catalytic, sensing, and energy storage capabilities. Here, we report the synthesis of highly dense MoO2/MoS2 core–shell nanoparticles, a new form of TMD nanostructure, via chemical vapor deposition using new growth geometry where a thin film of MoO3 was used as a source substrate for Mo as opposed to using MoO3 powder used in conventional studies. To grow the MoO2/MoS2 core–shell nanoparticles, we precisely control the carrier gas flow rate and sulfur vapor introduction time with respect to the melting of a MoO3 thin film used for Mo precursor. Scanning electron microscope image shows dense coverage of nanoparticles of 50–120 nm in size. The transmission electron microscopy image shows that the nanoparticles consist of crystalline MoO2 core covered with a few layer MoS2 shell. Raman and energy dispersive spectroscopy characterizations further confirm the chemical composition of the nanoparticle containing MoO2 and MoS2. We discuss the growth conditions under which the nanoparticles grow and elucidate its growth mechanism. We also discuss how a small but controllable changes in growth condition could lead to other highly dense growth of vertical/lateral MoO2/MoS2 plates in both source and growth substrates due to the unique growth geometry used in this study. [ABSTRACT FROM AUTHOR]

The aligned CdS nanorods are obtained by dispersing CdS in the conducting polyaniline matrix. The rods are about 50 nm in diameter and 400 nm in length. The significant changes of electronic absorption spectra of CdS nanorods and conducting polyaniline indicate the strong interaction between them. CdS—Polyaniline nanocomposites exhibit a three-dimensional Mott’s hopping process in the electrical conduction. Temperature variation of frequency dependent conductivity implies the correlated barrier hopping. The barrier height increases with the content of CdS. [ABSTRACT FROM AUTHOR]

Cancer in human society is one of the most problematic health issue responsible for outnumbered deaths worldwide. The consumption of developed NPs in cancer diagnosis is a rapidly emerging field of bio-medical nanotechnology. Recent years, greener synthesized metal oxide hybrid nanoparticles have attracted great attention in cytotoxicity to different cancer therapy. Herein, we report that Duchesnea indica plant mediated green synthesis plant extract mediated Zn doped CuO (Zn/CuO) nanoparticles (NPs) prepared by hydrothermal method and these physico-chemical properties were characterized by XRD, UV-DRS, FTIR, and SEM with EDAX analytical techniques. The XRD pattern findings indicated that the crystal structure of the base CuO matrix are not distorted by the substitution of Cu 2+ (0.73 Å) ions by Zn 2+ (0.65 Å) ions. The average crystallite size of undoped and Zn/CuO NPs samples are found to be in between the range of 23 to 36 nm. And we can see that the Zn/CuO NPs are large aggregates, containing small particles with sizes of 100–300 nm with spherical shaped morphology by SEM and TEM microscopic images. The normal cell viability and cancer cell inhibition results on A-498 cancer cells and also normal human epithelial cells exhibited that no significant changes in the cell viability with normal kidney epithelial cells and doped NPs given excellent cell inhibition treated on A-498 kidney tumor cells. [ABSTRACT FROM AUTHOR]

The vanadate-sillenite Bi 25 VO 40 nanoparticles were prepared through the facile Pechini method. The average size is about 70 nm. The sample was investigated by X-ray powder diffraction (XRD) and the structural refinement. The surface properties of the nanoparticles were investigated by the measurements such as the transmission electron microscopy (TEM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopic (XPS) and Brunauer–Emmett–Teller (BET) measurements. The nanoparticles have indirect allowed electronic transition and a narrow band gap of 2.31 eV. The photocatalysis was detected by the photodegradation of methylene blue (MB) solutions under the irradiation of visible-light. Hybridization of the 6s and 6p orbitals of Bi 3 + and the resulting lone electron pair yield interesting properties. The photocatalytic activity was discussed on the base of the structural characteristics such as the strong polarizing fields, rich oxygen ion vacancies, and high structure openness degree of the lattice. Bi 25 VO 40 nanoparticles could be potential in the application as a photocatalyst under visible light. [ABSTRACT FROM AUTHOR]

The field emission properties (FE) of a heteroarchitecture comprised of gadolinium hexaboride nanoparticles uniformly decorated over Cu2O nanoneedles (GdB6/Cu2O) have been investigated at the base pressure of ~1 × 10−8 mbar. Under the optimized pulsed laser deposition (PLD), a well-adhered coating of GdB6 nanoparticles on chemically synthesized cuprous oxide (Cu2O) nanoneedles has been obtained. A plausible growth mechanism of the hierarchical assembly of GdB6 nanoparticles on the Cu2O nanoneedles is explained on the basis of structural analysis carried out using SEM and TEM. A low turn-on field of ~2.3 V μm−1 (to draw an emission current density ~1 μA cm−2) is observed along with stable emission current at the preset value of ~2 μA over 4 h. The enhanced emission behaviour of the GdB6/Cu2O heteroarchitecture, in contrast to the pristine Cu2O nanoneedles, is attributed to its high aspect ratio and low work function. The observed FE results demonstrate GdB6/Cu2O heteroarchitecture as a potential candidate for application in various vacuum nano/microelectronic devices. [ABSTRACT FROM AUTHOR]

A one-pot multi-component, green, and highly efficient protocol has been described for the synthesis of a wide range of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones using TAPC supported on boehmite nanoparticles (BNPs-TAPC) as an eco-friendly and recyclable nanocatalyst in excellent yields under solvent-free conditions. A short reaction time, easy and quick isolation of the products, use of inexpensive heterogeneous nanocatalysts, a solvent-free process and excellent chemoselectivity are other remarkable features of this environmentally benign protocol. BNPs-TAPC was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and FT-IR methods. [ABSTRACT FROM AUTHOR]

We developed a novel sensor using carbon paste electrode (CPE) modified with cationic surfactant cetyltrimethylammonium bromide (CTAB) and the core-shell nanoparticles (NPs) of zinc oxide at copper (ZnO@Cu) to study an electrochemical behavior of 2, 4 - dichlorophenol (2, 4 - DCP), a harmful molecule. The core-shell ZnO@Cu NPs/CTAB/CPE is proved to be sensitive because of its sensing features for 2, 4-DCP. The sensor showed excellent electro-catalytic behavior and elevation in peak current in the presence of phosphate buffer solution (PBS) of 0.2 M strength. Advanced techniques like transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDS), and scanning electron microscope (SEM) were employed to ZnO@Cu core-shell NPs characterization. The cyclic voltammetry (CV), as well as square wave voltammetry (SWV) techniques, were applied to study electro-kinetic parameters, including specific heterogeneous rate constant, charge transfer coefficient, accumulation time, scan rate, the effect of temperature, pH, the energy of activation, enthalpy, entropy, Gibb's free energy, and the number of electrons transferred in the 2, 4 - DCP electro-oxidation. By SWV technique, the 2, 4 - DCP molecule was analyzed in vegetables, fruits, water, and soil samples. • The core-shell ZnO @ Cu nanoparticles along with CTAB were used to detect 2, 4-DCP. • The adsorption mechanism was in favour of monitoring an electrochemical process. • The irreversible electrochemical process involved two-electron transfer. • A detection limit value of 2, 4-DCP is 0.227 nM. [ABSTRACT FROM AUTHOR]

In this work, WMo nanopowders were prepared by sol-gel synthesis combined with hydrogen reduction. The phase distribution of the powders with calcination and reduction at different temperatures was analyzed to figure out the effect of temperature on the reaction process. The calcined powders were further analyzed by thermogravimetric analysis (TGA) and differential thermal analysis (DSC). The phase composition, grain size and powder morphology of the resulted WMo nanoparticles have been characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and transmission electron microscopy (TEM). The precursor calcined at 450 °C consisted of W 0.4 Mo 0.6 O 3 and MoO 3 phases which can be completely reduced to be pure WMo nanopowders with an average grain size of 20–40 nm at a low temperature of 700 °C for 1 h. The grain growth characteristics of the WMo nanopowders were investigated by analyzing the compacts annealed at temperatures ranging from 950 °C to 1400 °C for different time periods. The grain growth mechanism and the activation energy (Q g = 220 ± 21 kJ/mol) of WMo nanoparticles was also obtained. • WMo nanopowders were synthesized by sol-gel combined with H 2 reduction. • WMo nanopowders of 20–40 nm were obtained from precursors reduced at 700 °C. • The kinetics analysis of grain growth in WMo nanoparticles was unraveled. [ABSTRACT FROM AUTHOR]

In the present work, conventional chemical co-precipitation method was employed for the preparation of CdS nanoparticles. XRD studies reveal that CdS crystallizes in single phase hexagonal structure. The particle size of CdS nanoparticles is obtained as 13nm. Microstructural analysis using Scanning Electron Microscope (SEM) supplemented with EDAX were carried out for the sample to find grain size as well as chemical composition. SEM study reveals that the sample consist of nanoclusters, the grains have aggregated to form clusters. A detailed systematic study on CdS sample is done by characterizing TEM, UV-VIS-NIR spectra, Photoluminescence (PL) spectra, DSC/TGA and FTIR. [ABSTRACT FROM AUTHOR]

Poly (vinyl alcohol) (PVA) and poly (vinyl pyrrolidone) (PVP) nanofibers embedding Ag nanoparticles (5–18 nm) have been prepared successfully by electrospinning at room temperature. Scanning electron microscope (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Fourier transform IR spectra (FTIR), and Raman scattering were used to characterize the structure and properties of Ag nanoparticle-embedded PVA and PVP nanofibers before and after heat treatment at different temperature. The antibacterial activity of Ag nanoparticle-embedded PVP nanofibers after heat treatment was also tested, which indicated that the biological activity of yeast cells was effectively inhibited by these Ag nanoparticle-embedded PVP nanofibers. [ABSTRACT FROM AUTHOR]

pulgite@helical polyurethane composites (ATT@HPU and ATT@PU) were prepared after the surface modification of the attapulgite nano-fibrillar clay (ATT). ATT@HPU and ATT@PU were characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The results indicate that the helical polyurethane has been successfully grafted onto the surfaces of the modified ATT without destroying the original crystalline structure of ATT. The rod-like fibrous nanoparticles were confirmed by scanning electron microscope (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HTEM). The infrared emissivity of ATT@HPU and ATT@PU was also investigated. The results indicate that the singlehanded helical conformation is favored to the reduction of infrared emissivity due to the more regular structure and ordered stereo structures. [ABSTRACT FROM AUTHOR]

Abstract: Fe3O4 nanoparticles with different morphology such as sphere, nanowire, biscuit-like and quasi-cube were successfully prepared using a simple hydrothermal method. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The results showed that the morphology of product can be adjusted by changing the reaction conditions such as reaction time, different amount of surfactant added and the addition of organic solvent. In addition, the possible mechanism for the formation of different morphology under the corresponding reaction condition was suggested. [Copyright &y& Elsevier]

Silicon nitride nanowires or nanorods have been synthesized from SiCl4, NaN3, and metallic Mg at temperatures ranging from 200° to 300°C. X-ray powder diffraction patterns indicated that the as-obtained products were mainly β-Si3N4. Scanning electron microscope and high-resolution transmission electronic microscopy showed that the samples mostly consisted of Si3N4 nanowires or nanorods. As metallic iron powder was used, α-Si3N4 was mainly formed at 250°C. [ABSTRACT FROM AUTHOR]

With increasing interest in nanometer scale studies, a common research issue is the need to use different analytical systems with a universal substrate to relocate objects on the nanometer scale. Our paper addresses this need. Using the delicate milling capability of a focused ion beam (FIB) system, a region of interest (ROI) on a sample is labelled via a milled reference grid. FIB technology allows for milling and deposition of material at the sub 20-nm level, in a similar user environment as a standard scanning electron microscope (SEM). Presently commercially available transmission electron microscope (TEM) grids have spacings on the order 100 μm on average; this technique can extend this dimension down to the submicrometre level. With a grid on the order of a few micrometres optical, FIBs, TEMs, scanning electron microscopes (SEMs), and atomic force microscopes (AFM) are able to image the ROI, without special chemical processes or conductive coatings required. To demonstrate, Au nanoparticles of ∼ 25 nm in size were placed on a commercial Formvar®- and carbon-coated TEM grid and later milled with a grid pattern. Demonstration of this technique is also extended to bulk glass substrates for the purpose of sample location. This process is explained and demonstrated using all of the aforementioned analytical techniques. [ABSTRACT FROM AUTHOR]

In the present study, biocompatible manganese nanoparticles have been linked with zinc and iron molecules to prepare different derivatives of Mn0.5Zn0.5ErxYxFe2−2xO4 NPs (x = 0.02, 0.04, 0.06, 0.08, 0.10), using an ultrasonication approach. The structure, surface morphology, and chemical compositions of Mn0.5Zn0.5ErxYxFe2−2xO4 NPs were elucidated by X-ray diffractometer (XRD), High-resolution transmission electron microscopy (HR-TEM), scanning electron microscope (SEM), and Energy Dispersive X-Ray Analysis (EDX) techniques. The bioactivity of Mn0.5Zn0.5ErxYxFe2−2xO4 NPs on normal (HEK-293) and (HCT-116) colon cancer cell line was evaluated. The Mn0.5Zn0.5ErxYxFe2−2xO4 NPs treatment post 48 h resulted in a significant reduction in cells (via MTT assay, having an IC50 value between 0.88 µg/mL and 2.40 µg/mL). The specificity of Mn0.5Zn0.5ErxYxFe2−2xO4 NPs were studied by treating them on normal cells line (HEK-293). The results showed that Mn0.5Zn0.5ErxYxFe2−2xO4 NPs did not incur any effect on HEK-293, which suggests that Mn0.5Zn0.5ErxYxFe2−2xO4 NPs selectively targeted the colon cancerous cells. Using Candida albicans, antifungal activity was also studied by evaluating minimum inhibitory/fungicidal concentration (MIC/MFC) and the effect of nanomaterial on the germ tube formation, which exhibited that NPs significantly inhibited the growth and germ tube formation. The obtained results hold the potential to design nanoparticles that lead to efficient bioactivity. [ABSTRACT FROM AUTHOR]

A one-pot strategy was developed to coat micro- and nanomaterials with crystalline nanoparticles. Three Li-based materials were coated by a solution combustion synthesis method. By this procedure, we obtained LiCoO 2 nanoparticles covered with nanocrystals of NiO and Ag; LiMn 2 O 4 nanoparticles covered with Ag, and LiNi 0·5 Mn 1·5 O 4 microparticles covered with ZnO. The results confirm that the coating of the nano- and micro-particles was successful. The materials obtained were characterized morphologically and structurally. Using X-ray diffraction, Transmission Electron Microscopy (TEM), Scanning Electron Microscope (SEM), and Energy-dispersive X-ray Spectroscopy Mapping, the morphological uniformity and high crystallinity of the nano-coatings were confirmed. Therefore, this method makes it possible to obtain different coatings by varying the weight percentage of the coating material, yielding homogeneously coated materials, even at percentages as low as 0.5 wt%. The developed method has great advantages as it is simple, inexpensive, and easily scalable. Image 1 • Homogeneous coating with crystalline nanoparticles using a liquid method. • Solution combustion as an efficient method to coat micro and nano size materials. • Materials coated with crystalline nanoparticles in controlled weight ratios. • Method used to coat cathode materials for Li-ion batteries. • Simple, time- and energy-saving method. [ABSTRACT FROM AUTHOR]

• Melatonin/chitosan/hydroxypropyl methylcellulose nanoparticle was synthesized. • pH-responsive property for sustained melatonin release was shown. • Encapsulated melatonin nanoparticles showed high cytotoxicity against breast cancer cells. This work describes the development of novel pH-sensitive nanoparticles (NPs) for the delivery of melatonin (MLT) in breast cancer therapy. The MLT was encapsulated in composite NPs consisting of chitosan (CTS) and hydroxypropyl methylcellulose (HPMC) crosslinked in the presence of tripolyphosphate (TPP). The structure of the composite NPs was characterized using fourier transform infrared (FT-IR), wide angle X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The release behavior of MLT from the composite NPs were investigated in acidic and neutral medium in vitro. Cytotoxicity of MLT encapsulated in the NPs toward MDA-MB-231 breast cancer cells was measured using thiazolyl blue tetrazolium bromide assay (MTT) and compared with that of the free MLT. Results demonstrate that MLT encapsulated in CTS/HPMC NPs had higher toxicity toward the MDA-MB-231 cancer cells compared to the free MLT, thus making the NPs potentially useful in breast cancer therapy. [ABSTRACT FROM AUTHOR]

The structural, morphological, optical and mechanical properties of Zinc oxide (ZnO) nanoparticles annealed at different temperatures from 500 °C to 1000 °C with a step size of 100 °C were synthesized from Sol-Gel method. The X-ray diffraction study revealed that ZnO has hexagonal Wurtzite structure. Scanning Electron Microscope(SEM) images of the studied materials possess spherical morphology with induced porosity due to change in annealing temperature. The computed size of nanoparticles from Transmission Electron Microscopy (TEM) was 21 nm. The UV–Visible Spectroscopy revealed that the band gap decreased with increase of the temperature from 3.05eV to 2.82eV. Photoluminescence (PL) spectrum of ZnO nanoparticles shows that oxygen vacancy related defects increased as the temperature increases from 500 °C to 800 °C and decreased beyond 800 °C. The wear resistance of ZnO nanoparticles is found to increase with increase of temperature owing to the generation of oxygen vacancies. The maximum friction coefficient was assigned to largest grain size. • The computed size of nanoparticles from XRD and Tem was approximately 21 nm. • The UV–Visible Spectroscopy revealed that the band gap decreased from 3.29 eV to 3.24 eV with the increase in temperature. • Photoluminescence(PL) spectrum of ZnO nanoparticles shows oxygen vacancy related defect emissions such as orange and red. • The wear resistance of ZnO nanoparticles is found to increase with increase of temperature due to the reduction in the brittle nature of ZnO which is resulted from the generation of oxygen vacancies. • The higher friction coefficient is due to the large grain size of ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

There has been great progress in the 'green' chemistry approach for the synthesis of nanoparticles in recent years. Nanoparticles have gained special significance due to their unique properties. Herein we report a bioflocculant facilitated eco-friendly synthesis of copper nanoparticles (CuNPs). The copper nanoparticles were successfully synthesized through the reduction of copper sulphate (3 mM) solution by the bioflocculant (0.5 g). The synthesized nanoparticles were characterized by Scanning electron microscope equipped with elementary detector (SEM), X-ray diffractometer (XRD), Fourier Transform Infrared Spectrophotometer (FT-IR), Transmission electron microscopy (TEM), and UV spectroscope. CuNPs were applied in the treatment of both the domestic and industrial wastewater, removal of dyes and were confirmed for the antimicrobial effect against both Gram-negative and Gram-positive microorganisms. The synthesized nanoparticles showed great potential for industrial application when compared to the chemical flocculant. In comparison to FeCl 3 and bioflocculant, the nanoparticles were found to be effective in BOD and COD removal in coalmine wastewater samples. The highest flocculating activity and removal efficiency was observed at the lowest dosage of 0.2 mg/mL. Moreover, both the Minimal inhibitory concentration (MIC) and Minimal bactericidal concentration (MBC) were observed at the concertation of 12.5 μL. CuNPs nanoparticles were synthesized through reduction of copper sulphate salt by a polysaccharide bioflocculant. It flocculated effectively at 0.2 mg/mL and could remove all dyes. Also revealed that it possessed antimicrobial activity for both Gram-negative and Gram-positive organisms. Image 1 • CuNPs flocculate at low concentration of 0.2 mg/mL. • CuNPs showed some remarkable potential for dye removal. • Possesses the antimicrobial activity against both Gram-positive and Gram-negative. • Remove COB and BOD and Sulphate. [ABSTRACT FROM AUTHOR]

Hydrophobic Fe/Pt@Au core-shell nanoparticles (NPs) were synthesized in a quaternary CTAB/n-butanol/n-heptane/water reverse micelle. Dodecylthiol coated around the NPs as functional agent could be help the NPs to form a self-assembled monolayer of which can be viewed clearly by transmission electron microscopy (TEM). A scanning tunneling microscope (STM) was used to find the subtle self-assembled monolayer of the NPs and to measure their current-voltage characteristics as a function of the separation between the probe tip and the self-assembled monolayer of hydrophobic Fe/Pt@Au core-shell NPs on graphite. At room temperature, when the tip was positioned over the monolayer NPs on graphite, the current-voltage data showed 'Coulomb staircase' behavior. [ABSTRACT FROM AUTHOR]

• TiO 2 nanoparticles synthesized at 300 °C, 500 °C and 600 °C by SILAR-induced gelling method. • XRD results showed anatase and rutile phases • spherical nanoballs seen from the SEM images. • TEM and SAED patterns showed TiO 2. agglomerations. • Optical band gap energy ranging from 3.41 eV–3.60 eV. • Chemical vibrational bonds were evident from the FTIR and PL studies. Successive ionic layer adsorption and reaction (SILAR)-induced gelling method was adopted in synthesizing titanium dioxide nanoparticles, annealed at various temperatures so as to investigate their morphological, structural, optical, elemental, chemical bond and photoluminescence properties. Characterizations of the as-prepared nanoparticles were carried out using scanning electron microscope (SEM), X-ray diffractometer (XRD), transmission electron microscopy (TEM), selected area electron diffractometer (SAED), energy dispersive X-ray spectroscopy (EDX), UV–Visible spectrophotometer (UV–Vis), photoluminescence (PL) and fourier transform infrared (FTIR) spectroscopies. Nanospherical balls revealing anatase and rutile crystal structures at (1 0 1) and (1 1 0) planes respectively were observed. Agglomerations of chain-like small particles manifested in Debye-Scherrer′s rings were evident from the TEM and SAED patterns. EDX spectra revealed deposition of the major elemental constituents: Ti and O. High transmittance of about 80% with a band gap energy ranges for the anatase and rutile phases was obtained from the optical properties. Emission peaks arising from the PL spectra gave information on the charge transport and recombination rates occurring at the TiO 2 nanoparticles while FTIR studies revealed the chemical vibrational bonds of the deposited TiO 2 NPs. The obtained results make the deposited nanoparticles suitable for solar cell applications. [ABSTRACT FROM AUTHOR]