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Gold nanoparticles were synthesized by adapting an ecofriendly green method using aloe leaf extract. Aloe leaf extract acts both as stabilizing as well as reducing agent. The microwave method was adopted to prepare gold nanoparticles (GNPs). The formation of GNPs was observed using Ultraviolet surface plasmon resonance (UV-SPR) analysis. Morphology and characterization of GNPs were done by using Field emission scanning electron microscopy (FESEM), High resolution transmission electron microscopy (HRTEM), Fourier transforms infrared spectroscopy (FT-IR), and Energy dispersive x-ray analysis (EDAX) techniques. FESEM and HRTEM analysis showed that the morphology of the obtained GNPs was polygon-shaped. Crystalline nature was studied using X-ray diffraction (XRD) analysis. By applying the Scherrer formula, the average size of the GNPS was estimated to be 6±1nm. The catalytic activity of the prepared nanoparticles was studied by taking methyl red reduction as a model reaction. UV-VIS spectroscopy was used to follow the reaction by observing a change in absorbance with respect to time. The reaction is monitored under pseudo first order kinetics. [ABSTRACT FROM AUTHOR]

Recently, the core-shell structured black titanium dioxide (Black-TiO2) photocatalyst has attracted massive research interest due its improved photocatalytic properties and performance in various applications. In this paper, the synthesis of CS B-TiO2 is reported, and its structural properties are elucidated. The Black-TiO2 was synthesized by hydrolysis of titanium tetrachloride (TiCl4) in aqueous glycerol and post calcination at a low temperature of 300°C for 1h. The properties of the Black-TiO2 were determined using x-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) coupled with Fast Fourier Transform (FFT) and 3-dimension (3D) plots, field emission scanning electron microscopy (FESEM), diffuse reflectance UV-Visible spectroscopy (DRUV-Vis), and photoluminescence spectroscopy (PL). The performance of the Black-TiO2 was evaluated for the removal of phenolic compounds from real wastewater matrix under visible light irradiation. The results demonstrated anatase phase, particle size of 14.30 nm and an amorphous shell with a thickness of 1.5 nm surrounding the crystalline core of the Black-TiO2. Most importantly, the visible light absorption was enhanced, the bandgap was narrowed to 2.96 eV, and electron-hole pair recombination was considerably suppressed in Black-TiO2 which led to enhanced photocatalytic performance indicated by the 48.17% removal of the initial 224.85 mg/L phenolic compounds within 180 min of visible light irradiation. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide is synthesized hydrothermally taking molybdenum trioxide and sodium sulfide as precursors in 0.4 mol/l HCl solution. Three approaches were pursued by varying two parametric factors: synthesis time and synthesis temperature. The products formed were characterized and analyzed using High Resolution Transmission Electron Microscopy (HRTEM) images. The mechanism involved in the formation of MoS2 along with the changes observed on changing the parametric factors is discussed. The Hall effect measurements give an insight regarding the important transport parameters like resistivity, mobility, type of conductivity and their charge carrier concentration. Present study attempts to explain the influence of synthesis time and temperature on the final morphology and transport parameters of the MoS2 formed. [ABSTRACT FROM AUTHOR]

In this contribution, nanostructured BaZrO3 was prepared via a wet-chemical method combined with a thermal decomposition process. Thermal decomposition was studied using simultaneous thermal analysis (STA). Prepared BaZrO3 was analyzed X-Ray diffraction (XRD) and the morphology was studied by high-resolution transmission electron microscopy (HR-TEM). In the next step, BaZrO3 was mixed with YBCO superconductor (YBa2Cu3O7) in various ratios. Finally, the top-seeded melt growth process was applied for the synthesis of single-domain YBCO bulks with BaZrO3 serving as artificial pinning centers. [ABSTRACT FROM AUTHOR]

Materials Development (synthesis and characterization) of reduced graphene oxide (RGO), Lithium vanadium oxide (LVO), and Lithium manganese oxide (LMO) for the application of Lithium-ion batteries (LIB) are reported here. The synthesised materials were characterized by Raman spectroscopy and High Resolution Transmission Electron Microscopy techniques. The performance towards Battery application for the materials was done by Cyclic Voltammetry to realize the anode and cathode performances of the LMO and LVO materials. [ABSTRACT FROM AUTHOR]

Concern paper will report and discuss about a simple chemical synthesis method of liquid phase in co-precipitation growth method to produce a high quality zinc oxide nanorod where Zinc Nitrate Hexahydrate (Zn(NO3)2.6H2O) and Hexamethylene Tetramine (C6H12N4), Nitric acid (HNO3) are used as precursor. Zinc Oxide has a wide range of direct band gap energy of 3.3eV and high exciting binding energy 60meV. ZnO also has a high density of 5.606 grams/cm3. That's why Zinc Oxide nanorod using wide range of potential applications in various fields like medical applications, sensors, spintronic and piezoelectricity. Zinc oxide nanorod was synthesized by one dimensional. Developed zinc oxide nanorod have been investigated with high resolution scanning electron microscopy (HRSEM) and Energy Dispersive X-Ray Spectroscopy(EDX) and the obtained results revealed that the prepared zinc Oxide nano rods used in particularly electronics applications like sensors [ABSTRACT FROM AUTHOR]

Cerium oxide (CeO2) nanoparticles were synthesized by two different synthetic routes. Simple co-precipitation method was employed using ceric ammonium nitrate and NaOH as precursor. The first set of samples were treated at 600°C and second set of sample was prepared by microwave assisted heating instead of calcination. The effect of different stabilizing agents was studied using ethylene glycol, propylene glycol and diethylene glycol. The obtained samples were characterized by means of X-Ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HR-TEM), thermal analysis (TG), Langmuir surface area, pore volume and optical studies. A broad particle size distribution (16nm-24nm) was observed for CeO2 prepared by calcination method. Smaller particles (1.89 nm- 3.77nm) with narrow particle size distribution were obtainedfor microwave irradiated nano ceria. The morphology characteristics were analysed using HR-TEM and homogeneous, crystalline, spherical nano structures were visible. The SAED pattern revealed the highly crystalline nature of the sample. XRD data was in good agreement with TEM results. The XRD data was indexed with JCPDS File No. (34-0394). From the adsorption –desorption isotherms, the surface area was in the range of 10-20 m2/gand pore volume was around 0.001-0.0025 cm3/g. A strong blue emission was obtained for optical measurements. Thermal studies (TG) showed the stability in various temperature ranges. The properties of the microwave assisted nano ceria make them an advanced material suitable for use in various fields like catalysis, high tech ceramic applications etc. [ABSTRACT FROM AUTHOR]

As a major development in recent decades, thin films of carbon nanotubes (CNT) have emerged as a promising material suitable for many novel devices because of their exceptional electrical, optical and mechanical properties. The main goal of this work is to develop CNT based films and analyze its structure and morphology. Instead of preparing directly from carbon atoms, we have prepared films on amorphous substrates by thermal evaporation of commercially available multiwalled CNT powder from Sigma-Aldrich. Optical and structural properties were investigated through absorption, Raman and FTIR spectroscopy and high resolution Scanning Electron Microscopy and Atomic Force Microscopy. We have studied the optical damage of the prepared films using a pulsed Nd: YAG Laser. The films withstand an optical power in excess of ∼107 Wcm−2 under pulsed laser irradiation. [ABSTRACT FROM AUTHOR]

MgO thin films are grown on Si(100)-substrate by radio frequency (RF) sputtering technique and then implanted with transition metal (TM) ions i.e. Co, Cu and Ni. The ion implantation is performed at 100 keV with five fluences of 1 x 1015 (1E15), 5 x 1015 (5E15), 1 x 1016 (1E16), 2.5 x 1016 (2.5E16) and 5 x 1016 (5E16) ions/cm², respectively. Stopping and Range of Ions in Matter (SRIM) calculations and Transport of Ions in Matter (TRIM) simulations are performed to estimate the doping concentration, average vacancy/ion, projected range etc. for implanted ions. These calculations are further crosschecked using high resolution transmission electron microscopy (HRTEM) studies. X-ray absorption spectroscopy (XAS) measurements performed at metal K and L3,2 -edges reveal the valance state, co-ordination number to explore the electronic structure of modified MgOmatrix. [ABSTRACT FROM AUTHOR]

In this study, colloidal silver nanoparticles (AgNPs) were synthesized in situ using Bombyx mori silk sericin. The synthesized nanoparticles were analyzed using UV-Visible spectroscopy (UV-Vis), the absorption spectra showed peak at λ=413 nm. Fluorescence spectroscopy (FL) study, the morphological study was carried out using fluorescence spectrophotometer and field emission scanning electron microscopy (FESEM). The size and shape of the silver nanoparticles were analyzed using high resolution transmission electron microscopy (HR-TEM). The obtained results indicated the silk sericin as a bio template for the reduction of silver ions to silver neutral atoms. [ABSTRACT FROM AUTHOR]

Cerium oxide nanoparticles or nanoceria of average crystallite size ~ 6, 9 and 14 nm were synthesized by chemical co-precipitation method using deoxyribonucleic acid (DNA) as capping agent. Size dependent structural, optical and magnetic properties of prepared samples were investigated by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), UV-Visible diffuse reflectance spectroscopy and vibrating sample magnetometer (VSM) measurements. The increase in the value of optical band gap with decrease in particle size may be attributed to the quantum confinement effect. The saturation magnetization, coercivity and remanence increases as the particle size decreases from 14 nm to 9 nm. This is in view of the fact that increase in oxygen vacancies may produce magnetic moment by polarizing spins of f electrons of cerium ions located around them. The magnetic properties decreases below a critical size, since thermal energy can overcome the anisotropy and spontaneously reverse the magnetization of a particle from one easy direction to the other. The semiconducting properties along with room temperature ferromagnetism make DNA assisted synthesized nanoceria suitable for fabrication of next generation spintronic devices. [ABSTRACT FROM AUTHOR]

In this work, a facile method is proposed to synthesis graphene oxide (GO), reduced graphene oxide (rGO), silver and gold nanoparticles with 1:3 volume ratio decorated onto reduced graphene oxide (Ag1Au3/rGO). A chemical reduction route using sodium citrate as reducing agents have been used to prepared the as-synthesized samples. The produced samples have been characterized using Raman spectroscopy, UV-Visible, X-Ray Diffraction spectroscopy and High Resolution Transmission Electron Microscopy. The removal of oxygen containing groups from the graphene oxide to reduced graphene oxide was confirmed by intensity ratio (ID/IG) between the D and G band appeared at the peak. The change in optical properties of the product authenticated by the shift in the absorption peak and formation of silver and gold nanoparticles was determined by XRD spectroscopy. The morphological results illustrate that silver and gold nanoparticles decorated reduced graphene oxide formed stable dispersions and well distributed on the reduced graphene oxide surface with 10 nm – 40 nm of particle size. [ABSTRACT FROM AUTHOR]

Herein we report the resistive switching properties in ITO/Graphene Oxide (GOs)-PMMA Nanocomposite/Al sandwich devices. The devices were found to have write-once-read-many (WORM) nature and the value of set voltage was found to decrease withincreasing the amount of GOs nanofillers within PMMA matrix. GOs were synthesized by following conventional Hummer’s method. Nanocomposites were prepared by mixing GOs with different wt% of PMMA and spin-coated on ITO substrate to fabricate devices. SynthesizedGOs were characterized through various techniques such as X-Ray diffraction (XRD), scanning electron microscopy (SEM) and High resolution transmission electron microscopy (HRTEM). [ABSTRACT FROM AUTHOR]

The synthesis of gold nanoparticles using silk sericin (SS) extracted from Bombyx mori silk cocoons is an eco-friendly, low-cost, non-toxic, and facile method. The synthesis of biocompatible gold nanoparticles (AuNPs) by the redox reaction of chloroauric acid (HAuCl4.H2O) with SS is reported here. Synthesized SS-AuNPs were confirmed by the visual recognition of changes in color from pale yellow to pink color, and it was further confirmed by various analytical techniques. UV-visible spectroscopy (UV-vis) confirmed the formation of gold nanoparticles by showing surface plasmon resonance (SPR) strong peak at λ= 520nm. Fourier transmission infrared (FT-IR) spectroscopy reveals the presence of secondary functional groups involved in redox reaction. High resolution transmission electron microscopy (HR-TEM) illustrated the formed AuNPs are spherical in shape with highly crystalline nature. Dynamic light scattering (DLS) study reveals the average particles size and size distribution of the SS-AuNPs present in the solution. [ABSTRACT FROM AUTHOR]

A comparison on Photo-catalytic activity of pure and Ag-ZnS nanocomposites using histidine as a capping agent have been reported here. The synthesized samples were characterized by X-ray diffraction spectroscopy, Field emission scanning electron microscopy, High resolution transmission electron microscopy and Ultraviolet-Visible spectroscopy. The photocatalytic activity of as-prepared samples were investigated under sunlight using Rhodamine B. The photocatalytic activity of ZnS was observed to be decreased by the incorporation of Ag. [ABSTRACT FROM AUTHOR]

In the present work, highly efficient blue emitting Ce3+ doped ZnWO4 nanophosphors were successfully synthesized by simple hydrothermal technique. The nanophosphors were then characterized by using the X-ray powder diffraction (XRD), Rietveld refinement of XRD, Field Emission Scanning Electronic Microscopy (FESEM), High resolution transmission electron microscopy (HRTEM) and Photoluminescence spectroscopy (PL). The as prepared nanophosphors display intense blue emission having a broad peak with maxima at 464 nm under 283 nm UV excitation which enhances by Ce3+ doping. Color purity of the samples are also enhanced due to the doping of the rare earth activator in the ZnWO4 matrix. Obtained results prove that this nanophosphor is suitable to compete in the rapidly growing field of solid-state lighting and field emission display devices. [ABSTRACT FROM AUTHOR]

New goals for providing better solutions with the help of nanotechnology have emerged from the electronics industry. Nano-electronics has focused on the structural, optical, magnetic, and photoluminescence properties of nanomaterials for developing optoelectronic devices. These properties play a vital role at the nanoscale level in comparison to that of bulk compounds. The use of semiconductor materials has always been in demand. Here, we are focusing on the unique and distinct structural and optical properties of rare earth-doped ZnO nanostructures. Nanoparticles of ZnO doped with Terbium ion was prepared by sol gel method. Systematic structural studies on Tb3+ ion doped ZnO nanocrystals were carried out using X-ray diffraction, High resolution transmission electron microscopy, Xray photoelectron spectroscopy and EPR study. X-Ray photoelectron spectroscopy and EPR studies spectroscopy measurements were also performed on these nanoparticles to observe the surface property alteration done by rare earth incorporation. It was observed that by incorporation of Tb3+ ions, the broad band luminescence has enhanced which could be exploited for the fabrication of display devices of required luminescence. The EPR study shows that the type of surface defects changes for different concentration of Tb doped in the ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

In the present study silver, gold and their alloy (Au1-xAgx (x = mole fraction of gold)) nanoparticles have been prepared under microwave irradiations. The prepared nanoparticles have been characterized using UV-Vis spectroscopy and high resolution transmission electron microscopy (HRTEM). The observance of single Surface Plasmon resonance (SPR) peak in the absorption spectra of Au1-xAgx alloy solutions attributed to the homogeneous formation of bimetallic alloy nanoparticles. There is linear red shift in observed SPR peak with increase in mole fraction (x). TEM images reveal the spherical shape of prepared Au1-xAgx alloy nanoparticles with average size ranging from ~ 4 - 17nm. The observed SPR peak have also been simulated using Mie Theory and DDA method. [ABSTRACT FROM AUTHOR]

Owing to the unique optical properties, core-shell nanoparticles are receiving increasing attention from the scientific community and have widespread applications in high-resolution optical imaging, enhanced light absorption in photovoltaic and photocatalysis etc. The present research work reports the synthesis of Au-Ag core-shell nanoparticles based nanocomposites with polyvinyl alcohol (PVA) as the host matrix. Morphological analysis of the prepared nanocomposites was carried out using high resolution transmission electron microscopy (HRTEM). Further UV-visible absorption spectroscopy was utilized to study the optical properties such as absorption coefficient (α), optical energy gap (Eg) and Urbach’s energy (Eu) of thus synthesized Au-Ag core-shell PVA nanocomposite. [ABSTRACT FROM AUTHOR]

Present investigation aims the synthesis and characterization of Zinc oxide (ZnO) nanoparticles using Annonna Muricata leaf by means of safe, non-toxic, and ecofriendly green method. Structure and crystallite size of the product were examined by X-ray Diffraction analysis (XRD). XRD analysis reveals crystalline nature with hexagonal wurtzite structure in the space group of P63mc having average crystallite size of 21 nm. Peak at 418 cm−1 in Fourier Transform Infrared Spectra (FTIR) corresponds to Zn-O stretching which confirm the formation of ZnO nanoparticles. High Resolution Transmission Electron Microscopy (HRTEM) shows irregular shape particles. Ring nature of Selected Area Diffraction (SAED) pattern indicates poly crystalline nature. UV-Visible spectrum shows a characteristic absorption peak of ZnO nanoparticles at wavelength of 350 nm having optical band gap of 3.14 eV. The morphological characterization of synthesized nanoparticles was done by Field Emission Scanning Electron Microscopy (FESEM) shows agglomerated nanostructures. Energy Dispersive X-Ray analysis (EDX) confirm ZnO nanoparticles with Zn and O atoms. Dielectric measurements have been carried out on sintered pellet in the frequency range 1Hz-100MHz at room temperature. The value of dielectric constant (ε ’) and dielectric loss tangent (tan δ) was decreases with increase in frequency. [ABSTRACT FROM AUTHOR]

Nano iron cerium tungstate has been successfully prepared by the effective chemical precipitation method followed by calcination at 600 °C. The X-ray diffraction result verifies that the calcined sample is crystallized in the triclinic structure with space group P... and the particles are in nanometer size. The optical absorption tale of the material starts in the visible region at 660 nm. The crystalline planes grown are visible from the high resolution transmission electron microscopy images and the selected area diffraction patterns. The dielectric constant and dielectric loss values obtained at 1 MHz are 20 and 0.142, respectively. [ABSTRACT FROM AUTHOR]

The peculiar ternary full Heusler alloy Sr2CoSn nanoparticles are synthesized by co-precipitation method. X- ray diffraction pattern confirms the formation of XA or Xα structure of Sr2CoSn. Using Williamson–Hall plot (W–H plot), we are able to use the uniform deformation model and get low value of strain induced broadening. UV-Visible absorption spectrum shows sharp absorption peak at 210 nm and the estimated band gap energy of Sr2CoSn Heusler alloy nanoparticles is Eg = 4.6 eV (from Tauc plot). The presence of Sr2CoSn with the particle size of approximately 90 nm was observed using high resolution scanning electron microscopy. The magnetization measurements were carried out using VSM and studied M verses H hysteresis studies. [ABSTRACT FROM AUTHOR]

In this work, we have synthesized cetyltrimethyl ammonium bromide (CTAB) mixed cobalt ferrite (CoFe2O4) nanoparticles (NPs) using sol-gel auto-combustion method taking a different weight percent ratio of CTAB i.e., 0%, 1%, 2%, 3% and 4% with respect to metal nitrates. The morphological, structural and magnetic properties of these NPs are characterized by high resolution transmitted electron microscopy (HRTEM), X-ray diffraction (XRD), Raman spectrometer and physical property measurement system (PPMS). It has been found that saturation magnetization of cobalt ferrite increases with increase in crystalline size of the NPs. Saturation magnetization and crystallite size both were found to be lowest in the case of sample containing 2% CTAB. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) and Polyaniline/CuO nanocomposite have been synthesized by using electrochemical deposition method. The composite was characterized using Fourier transform infra-red spectroscopy (FT-IR) to confirm the chemical interaction changes, micro structural morphology was done by Field Emission Scanning Electronic Microscopy (FESEM) and High Resolution Transmission Electron Microscopy (HRTEM). The dielectric constant and AC conductivity are found to increases with increase in temperature range (303 to 393K), these results shows enhancement in electrical conductivity due to effect of nanocomposite. [ABSTRACT FROM AUTHOR]

Nanocrystalline pyrochlore material Dysprosium Titanate (Dy2Ti2O7) has been synthesized through a single step optimized combustion route. The phase purity and phase formation of the combustion product has been characterized using X-Ray diffraction analysis (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) analysis. X-Ray diffraction analysis (XRD) reveal that Dy2Ti2O7 is highly crystalline in nature with cubic structure in the Fd3m space group. The microstructures and average particle size of the prepared nanopowder were examined by High Resolution Transmission Electron Microscopy (HR-TEM). The optical band gap of the Dy2Ti2O7 nanoparticles is determined from the absorption spectrum, was attributed to direct allowed transitions through optical band gap of 3.98 eV. The frequency dependent dielectric measurements have been carried out on the sintered pellet in the frequency range 1 Hz-10 MHz. The measured value of dielectric constant (ℇ’) was ∼ 43 and loss tangent (tan δ) was 4×10−3 at 1 MHz, at room temperature. [ABSTRACT FROM AUTHOR]

The liquid bridge rupture confined between two glass plates is experimentally investigated. High-resolution shadow technique is used for video registration. Critical bridge diameters and distance between glass plates are found. [ABSTRACT FROM AUTHOR]