Green Synthesis and Characterization of Nickel Tungsten Bimetallic Oxide Nanoparticles via Microwave Irradiation Technique

2021 ◽  
Vol 25 (12) ◽  
pp. 76-81
Author(s):  
S. Krishnaja ◽  
Kumar V.G. Viju ◽  
V.G. Vidya
Keyword(s):  
Microwave Irradiation ◽  
Synthesis Method ◽  
Visible Region ◽  
Visible Spectrum ◽  
Polyol Synthesis ◽  
Oxide Nanoparticles ◽  
Energy Dispersion Spectroscopy ◽  
Transmission Electron ◽  
Uv Visible ◽  
Nickel Tungsten

Nickel tungsten bimetallic oxide nanoparticles were synthesised in ethylene glycol using microwave irradiation technique. Nickel and tungsten oxide nanoparticles were synthesised separately using microwave assisted polyol synthesis method. The respective systems are combined together in ratio 1:1 molar and are subjected to microwave irradiation to get Ni-W bimetallic oxide. The structure and composition of nanoparticles were characterised by UV-Visible Spectroscopy, FT-IR Spectroscopy, X-Ray Diffraction (XRD), Energy Dispersion Spectroscopy (EDS), Transmission Electron Microscopy (TEM), Photoluminescence Spectroscopy (PL) and Magnetic Susceptibility measurements. From the XRD and FTIR measurements, nanocrystalline Wolframite structure of Ni-W bimetallic oxide nanoparticles was established. The emperical formula of the nanoparticle is found as Ni0.4W0.6O2.6. The composition may be varied by changing the ratio of Ni and W. A maximum absorbance of 385nm was obtained in UV-Visible spectrum and three emission peaks were obtained in the visible region of photoluminescent studies. Further studies can be done on the catalytic and electrochromic properties of the substance.

Structural, Morphological, Magnetic and Self-Heating Studies of One-Step Polyol Synthesized Manganese Ferrite (MnFe2O4) Nanoparticles

2019 ◽  
Vol 19 (01) ◽  
pp. 1950003
Author(s):  
P. R. Ghutepatil ◽  
S. H. Pawar
Keyword(s):  
Room Temperature ◽  
Synthesis Method ◽  
Average Crystallite Size ◽  
Superparamagnetic Nanoparticles ◽  
Polyol Synthesis ◽  
X Ray Diffraction ◽  
Self Heating ◽  
Transmission Electron ◽  
One Step ◽  
Mnfe2o4 Nanoparticles

In this paper, uniform and superparamagnetic nanoparticles have been prepared using one-step polyol synthesis method. Structural, morphological and magnetic properties of obtained MnFe2O4 nanoparticles have been investigated by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and thermogravimetric analysis (TGA) techniques. Structural investigation showed that the average crystallite size of obtained nanoparticles was about 10[Formula: see text]nm. Magnetic study revealed that the nanoparticles were superparamagnetic at room temperature with magnetization 67[Formula: see text]emu/g at room temperature. The self-heating characteristics of synthesized MnFe2O4 nanoparticles were studied by applying external AC magnetic field of 167.6 to 335.2[Formula: see text]Oe at a fixed frequency of 265[Formula: see text]kHz. The SAR values of MnFe2O4 nanoparticles were calculated for 2, 5, 10[Formula: see text]mg[Formula: see text]mL[Formula: see text] concentrations and it is observed that the threshold hyperthermia temperature is achieved for all concentrations.

scholarly journals Preparation of Fe-DopedTiO2Nanotubes and Their Photocatalytic Activities under Visible Light

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Honghui Teng ◽  
Shukun Xu ◽  
Dandan Sun ◽  
Ying Zhang
Keyword(s):  
Visible Light ◽  
Visible Region ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Photocatalytic Activities ◽  
Ultrasonic Assisted ◽  
Uv Visible

Fe-doped TiO2nanotubes (Fe-TNTs) have been prepared by ultrasonic-assisted hydrothermal method. The structure and composition of the as-prepared TiO2nanotubes were characterized by transmission electron microscopy, X-ray diffraction, and UV-Visible absorption spectroscopy. Their photocatalytic activities were evaluated by the degradation of MO under visible light. The UV-visible absorption spectra of the Fe-TNT showed a red shift and an enhancement of the absorption in the visible region compared to the pure TNT. The Fe-TNTs were provided with good photocatalytic activities and photostability and under visible light irradiation, and the optimum molar ratio of Ti : Fe was found to be 100 : 1 in our experiments.

Preparation of Polyaniline Supported TiO2 Photocatalyst and its Photocatalytic Property

2011 ◽  
Vol 356-360 ◽  
pp. 524-528 ◽  
Author(s):  
Chun Ling Yu ◽  
Rui Xue Wu ◽  
Ying Huan Fu ◽  
Xiao Li Dong ◽  
Hong Chao Ma
Keyword(s):  
Electron Microscopy ◽  
Hydrothermal Process ◽  
Photocatalytic Property ◽  
Visible Spectrum ◽  
X Ray Diffraction ◽  
Visible Spectroscopy ◽  
Anthraquinone Dye ◽  
X Ray ◽  
Transmission Electron ◽  
Uv Visible

A polyaniline supported titanium dioxide photocatalyst was prepared by an impregnation-hydrothermal process and characterized by powder X-ray diffraction, transmission electron microscopy and UV-visible spectroscopy. It was found that the TiO2 nanoparticles were well dispersed on the surface of the polyaniline and the photocatalyst has a stronger absorption compared with that of pure TiO2 over the whole of the visible spectrum. The photocatalyst exhibited higher photocatalytic activity than pure TiO2 for the photodegradation of solutions of the anthraquinone dye, reactive brilliant blue KN-R, under visible light irradiation.

Synthesis of ZnO Nanoparticles Doped with Cobalt: Influence of Doping on the Magnetic and Fluorescent Properties

2016 ◽  
Vol 869 ◽  
pp. 982-986
Author(s):  
Henrique J. Sugahara ◽  
Etelino F. de Melo ◽  
Celso P. de Melo ◽  
Kleber G.B. Alves
Keyword(s):  
Zno Nanoparticles ◽  
Visible Region ◽  
Cobalt Doping ◽  
X Ray Diffraction ◽  
Fluorescent Properties ◽  
Transmission Electron ◽  
Co Concentration ◽  
Crystallite Sizes ◽  
Uv Visible ◽  
Co Precipitation

We have investigated the influence of cobalt doping on the luminescent and magnetic properties of ZnO nanoparticles prepared by co-precipitation. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), photoluminescence (PL) and by use of a vibrating sample magnetometer (VSM). XRD analyses revealed a standard ZnO wurtzite crystal structure and showed that the cobalt doped ZnO nanoparticles (ZnO:Co_NPs) were synthetized without impurities. The calculation based on the XRD shows the average crystallite sizes of ZnO to be in the 8-11 nm range. TEM images of ZnO and ZnO:Co indicated that these nanoparticles are nearly uniformly spherical with a diameter of about 10 - 15 nm. The PL spectra exhibited high [low] intensity in the UV [visible] region. While the PL shows a decreasing intensity with increasing doping doses, the peak at 544nm is not present in the cobalt-doped zinc oxide, and a the peak at 378 nm shifts to 390nm. The VSM measurement confirmed the presence of ferromagnetism and we observed an increase in the values of the saturation magnetization with increasing Co concentration.

Structural Characterization of Nanoparticles Obtained by a Polyol Synthesis in the Bimetallic System Pt-Pd

2012 ◽  
Vol 1372 ◽  
Author(s):  
A. F. García-Ruiz ◽  
J. J. Velázquez Salazar ◽  
R. Esparza ◽  
N. Castillo
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Bimetallic Nanoparticles ◽  
Synthesis Method ◽  
Shell Structures ◽  
Polyol Synthesis ◽  
Core Shell ◽  
Thermal Methods ◽  
Transmission Electron ◽  
Bimetallic System

ABSTRACTA modified polyol synthesis has been utilized to study the different structures obtained in the bimetallic system of platinum (Pt) and palladium (Pd). Some results are shown in this work. Thermal methods under refluxing, carrying on the reaction up to 285 ºC, have been assayed to reduce metallic salts using ethylene glycol (EG) as reducer and polyvinylpyrrolidone (PVP) as protective reagent of the formed bimetallic nanoparticles. The special core-shell structure has been observed in these bimetallic nanoparticles, whose synthesis was assisted by Ag, showing polyhedral shapes. The average diameter size of the core has been estimated at 10 nm, and the diameter size of the shell in 13 nm, consequently the thickness of the shell is around 1.5 nm. Nanoparticles were structurally characterized with transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) equipped with detector to generate high angle annular dark field (HAADF) images. This kind of structures have been studied and utilized to increase successfully the catalytic properties of monometallic nanoparticles of Pt or Pd according to other works. Here, the synthesis procedure is described; as the main results, several images are presented showing the obtained bimetallic core-shell structures and their fast Fourier transform (FFT), and also the size and the elemental analysis of the nanoparticles are reported, concluding that this synthesis method is very efficient for preparing bimetallic core shell structures.

scholarly journals Synthesis and Characterisations of Reduced Graphene Oxide Prepared by Microwave Irradiation with Sonication

2021 ◽  
Vol 32 (2) ◽  
pp. 1-13
Author(s):  
Fika Fauzi ◽  
Fayyad Azizi ◽  
Muhammad Miqdam Musawwa ◽  
Wipsar Sunu Brams Dwandaru
Keyword(s):  
Graphene Oxide ◽  
Microwave Irradiation ◽  
Mass Production ◽  
Functional Group ◽  
Scale Up ◽  
Synthesis Method ◽  
Oxygen Functional Group ◽  
Reduced Graphene ◽  
Uv Visible ◽  
Sonication Technique

Recently, reducing graphene oxide (GO) through microwave irradiation has been extensively explored in order to scale up the mass production of graphene. We report the simple technique to reduce GO by means of microwave irradiation combined with a sonication technique. The microwave-reduced GO (MWrGO) is formed by exposing a microwave onto GO powder in order to reduce the oxygen functional group and then followed by exfoliating via a sonication method. The time exposure of the microwave irradiation was 20 min with the powers of 450 W and 800 W. The UV-visible (UV-vis) spectra showed the evolution of GO into MWrGO indicated by the red shift of the absorption peak from 230 nm to 267 nm and disappearance of the shouldering peak at 300 nm. The reduction of the oxygen functional group has been proved by Fourier transform infrared (FTIR) spectra. Furthermore, the scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) data demonstrated further confirmation of the reduction of GO and the formation of basal planes of sp2 carbon clusters of the sample due to the treatment. The EDS spectra revealed that the MWrGO by 800-W-irradiation had much less oxygen functional groups and much more carbon content than GO. The proposed synthesis method is simple and readily controlled for a mass production of graphene from GO.

scholarly journals Synthesis and application of pigments based on lanthanide orthoferrites

2020 ◽  
Vol 14 (2) ◽  
pp. 161-167
Author(s):  
Patrícia Pimentel ◽  
Jairo Dutra ◽  
Maria Câmara ◽  
Gerbeson Dantas ◽  
Osmar Bagnato ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Perovskite Phase ◽  
Visible Region ◽  
Ceramic Pigments ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Uv Visible ◽  
Cie Lab

In this work, we synthesized oxides with perovskite LnFeO3 type structure (where Ln = La, Pr and Nd), aiming their use as ceramic pigments. The as-synthesized powders, prepared by gelatin method, were thermally treated at 600 and 800 ?C to obtain the perovskite phase. The characterization was performed using X-ray diffraction technique, followed by Rietveld refinement, scanning and transmission electron microscopy, spectroscopy in the UV-Visible region and CIE Lab colorimetry. The calcined powders were also used for fabrication of ceramic pieces to evaluate the colour when 2 wt.% of the powders was added into a transparent glaze. The pigments presented shades ranging from pale brown for the powdered samples to yellowish when applied in the glazes.

Application of Modified PANI-ZnO Composites for NH3Gas Sensor at Ambient Temperature

2020 ◽  
Vol 42 (3) ◽  
pp. 390-390
Author(s):  
Naimat Ullah Naimat Ullah ◽  
Anwar Ul Haq Ali Shah Anwar Ul Haq Ali Shah ◽  
Fazal Akbar Jan Fazal Akbar Jan ◽  
Rotaba Ansir Rotaba Ansir ◽  
Wali Muhammad Wali Muhammad
Keyword(s):  
Thin Film ◽  
Zinc Oxide ◽  
Ambient Temperature ◽  
Zinc Oxide Nanoparticles ◽  
Gas Sensing ◽  
Visible Spectrum ◽  
Xrd Analysis ◽  
Oxide Nanoparticles ◽  
Ammonia Gas ◽  
Uv Visible

Polyaniline and zinc oxide nanoparticles were successfully synthesized through inverse emulsion polymerization method and hydrothermal method respectively. For ammonia gas sensing using LCR meter thin film of the composite was fabricated by using spin coater. The functional groups, morphological, optical, structural properties of zinc oxide nanoparticles, polyaniline (emeraldine salt) and composites were investigated by FTIR spectroscopy, Scanning electron microscopy (SEM), UV- Visible spectroscopy and XRD analysis. The formation of ZnO particles of different shapes in the nano range was confirmed from UV-visible and XRD analysis. UV visible spectrum shows the formation of nanoparticles of ZnO. Thin film of Polyaniline/zinc oxide composites were deposited on the surface of copper interdigitated electrode. The fabricated device showed sensitivity to ammonia gas (NH3) at ambient temperature (300 K). It was observed that the resistance is decreases with the increase of volume of ammonia gas. The electrical properties were also investigated of the different concentration of nanocomposite. Optimum sensing response was achieved with PANI in the presence of 50 wt% ZnO nanoparticles. It may also be inferred from this study that the solution mixing process to produce composites has promising future if handled carefully.

Green Synthesis of Selenium Nanoparticle using Capparis decidua fruit extract and its Characterization using Transmission Electron Microscopy And UV- Visible Spectroscopy

2021 ◽  
pp. 2129-2132
Author(s):  
B. Madhumitha ◽  
Preetha Santhakumar ◽  
M. Jeevitha ◽  
S. Rajeshkumar
Keyword(s):  
Green Synthesis ◽  
Synthesis Method ◽  
Visible Spectroscopy ◽  
Traditional System ◽  
Selenium Nanoparticle ◽  
Transmission Electron ◽  
Medicinal Properties ◽  
Uv Visible ◽  
Capparis Decidua

Capparis decidua is used in the traditional system of medicine used due to its medicinal properties. Selenium nanoparticle was synthesized in a simple and rapid way by green synthesis method. Selenium nanoparticle was synthesized using aqueous extract of Capparis decidua fruit. The aim of this present study is to synthesize and to analyse the characterization of selenium nanoparticle synthesized using Capparis decidua. Characterization of selenium nanoparticle was done using ultra-visible spectroscopy and Transmission electron microscope [TEM]. Initially, the wavelength obtained for synthesized selenium nanoparticles ranged from 300nm to 600nm. Then TEM was carried out to find the size and shape of the nanoparticle. The selenium nanoparticle was spherical in shape with size of 320nm. The present study concluded that the selenium nanoparticle prepared using Capparis decidua was ecofriendly and may serve and benefit the society because of its rich medicinal property with less side effects if further research is carried out.

Biosynthesis of Silver Nanoparticles from Eucalyptus corymbia Leaf Extract at Optimized Conditions

2019 ◽  
Vol 25 ◽  
pp. 32-45 ◽  
Author(s):  
Munyao Joshua Sila ◽  
Michira Immaculate Nyambura ◽  
Deborah Atieno Abong’o ◽  
Francis B. Mwaura ◽  
Emmanuel Iwuoha
Keyword(s):  
Silver Nanoparticles ◽  
Plant Extract ◽  
Narrow Range ◽  
Visible Spectrum ◽  
Extraction Temperature ◽  
Transmission Electron ◽  
Uv Visible ◽  
Silver Nitrate Concentration ◽  
The Fourier Transform ◽  
20 Nm

This study reports the biosynthesis of narrow range diameter silver nanoparticles at optimum conditions usingEucalyptus corymbiaas a reducing and stabilizing agent. Optimal conditions for biosynthesis of silver nanoparticles (AgNPs) were found to be; an extraction temperature of 90°C, pH of 5.7 a Silver Nitrate concentration of 1mM and AgNO3to plant extract ratio of 4:1. UV-Visible spectroscopy monitored the formation of colloidal AgNPs. The UV-Visible spectrum showed a peak around 425 nm corresponding to the Plasmon absorbance of the AgNPs. The size and shape characterization of the AgNPs was done using Transmission Electron Microscopy (TEM) techniques which revealed narrow range diameter (18-20 nm), almost monodispersed AgNPs, spherical in nature and with minimal agglomeration. Energy Dispersive X-ray (EDX) results showed the presence of two peaks at 3.0 and 3.15 keV in the silver region. The Fourier Transform Infrared-Spectra (FTIR) of the plant extract and the AgNPs gave rise to vibrational peaks at 3260 and 1634 wavenumbers which are due to the presence of OH and –C=C-functional groups respectively.

Sign in / Sign up

Export Citation Format

Share Document