scholarly journals New Electrospun ZnO:MoO3 Nanostructures: Preparation, Characterization and Photocatalytic Performance

Nanomaterials ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1476 ◽  
Author(s):  
Petronela Pascariu ◽  
Mihaela Homocianu ◽  
Niculae Olaru ◽  
Anton Airinei ◽  
Octavian Ionescu
Keyword(s):  
Photocatalytic Performance ◽  
Molybdenum Trioxide ◽  
Blue Shift ◽  
Band Gap Energy ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Electron Microscopies ◽  
Reaction Rate Constants ◽  
Transmission Electron ◽  
Electrospinning Method

New molybdenum trioxide-incorporated ZnO materials were prepared through the electrospinning method and then calcination at 500 °C, for 2 h. The obtained electrospun ZnO:MoO3 hybrid materials were characterized by X-ray diffraction, scanning and transmission electron microscopies, ultraviolet (UV)-diffuse reflectance, UV–visible (UV–vis) absorption, and photoluminescence techniques. It was observed that the presence of MoO3 as loading material in pure ZnO matrix induces a small blue shift in the absorption band maxima (from 382 to 371 nm) and the emission peaks are shifted to shorter wavelengths, as compared to pure ZnO. Also, a slight decrease in the optical band gap energy of ZnO:MoO3 was registered after MoO3 incorporation. The photocatalytic performance of pure ZnO and ZnO:MoO3 was assessed in the degradation of rhodamine B (RhB) dye with an initial concentration of 5 mg/L, under visible light irradiation. A doubling of the degradation efficiency of the ZnO:MoO3 sample (3.26% of the atomic molar ratio of Mo/Zn) as compared to pure ZnO was obtained. The values of the reaction rate constants were found to be 0.0480 h−1 for ZnO, and 0.1072 h−1 for ZnO:MoO3, respectively.

scholarly journals ZnFe2O4-TiO2Nanoparticles within Mesoporous MCM-41

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Aidong Tang ◽  
Yuehua Deng ◽  
Jiao Jin ◽  
Huaming Yang
Keyword(s):  
Sol Gel ◽  
Rutile Phase ◽  
Band Gap Energy ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Agglomeration Of Nanoparticles ◽  
Adsorption Desorption ◽  
Mcm 41

A novel nanocomposite ZnFe2O4-TiO2/MCM-41 (ZTM) was synthesized by a sol-gel method and characterized through X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), N2adsorption-desorption, Raman spectroscopy, and ultraviolet visible (UV-vis) spectrophotometry. The results confirmed the incorporation of ZnFe2O4-TiO2nanoparticles inside the pores of the mesoporous MCM-41 host without destroying its integrity. ZnFe2O4nanoparticles can inhibit the transformation of anatase into rutile phase of TiO2. Incorporation of ZnFe2O4-TiO2within MCM-41 avoided the agglomeration of nanoparticles and reduced the band gap energy of TiO2to enhance its visible light photocatalytic activity. UV-vis absorption edges of ZTM nanocomposites redshifted with the increase of Zn/Ti molar ratio. The nanocomposite approach could be a potential choice for enhancing the photoactivity of TiO2, indicating an interesting application in the photodegradation and photoelectric fields.

scholarly journals Preparation of Cd-Loaded In2O3Hollow Nanofibers by Electrospinning and Improvement of Formaldehyde Sensing Performance

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Ruijin Hu ◽  
Jing Wang ◽  
Pengpeng Chen ◽  
Yuwen Hao ◽  
Chunli Zhang ◽  
...  
Keyword(s):  
Molar Ratio ◽  
Formaldehyde Concentration ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Grain Sizes ◽  
Transmission Electron ◽  
Electrospinning Method ◽  
Formaldehyde Sensing ◽  
Small Grains

Pure In2O3and Cd-loaded In2O3hollow and porous nanofibers with different Cd/In molar ratios (1/20, 1/10, 1/1) were synthesized by electrospinning method. X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), and transmission electron microscopy (TEM) were used to characterize the nanofibers. The porous nanofibers were composed of small grains. The average grain sizes and the diameters of Cd-loaded In2O3nanofibers increased with the increasing of Cd/In molar ratios. The formaldehyde sensing properties of the sensors based on pure In2O3and Cd-loaded In2O3nanofibers were investigated in formaldehyde concentration range of 0.5∼100 ppm. Moreover, the selectivity of those sensors was studied by testing responses to methanol, toluene, ethanol, acetone, and ammonia. The result showed that Cd-loaded In2O3nanofibers with Cd/In molar ratio of 1/10 possessed the highest response value and good selectivity at operating temperature 280°C. In addition, the formaldehyde sensing mechanism of the sensors based on Cd-loaded nanofibers was briefly analyzed.

Facile Synthesis and Photocatalytic Performance of W18O49 Nanorods

2017 ◽  
Vol 726 ◽  
pp. 360-364
Author(s):  
Shuo Wang ◽  
Xia Xia Bai ◽  
Hui Zhang
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Performance ◽  
Band Gap Energy ◽  
Xenon Lamp ◽  
X Ray Diffraction ◽  
Facile Synthesis ◽  
X Ray ◽  
Photodegradation Efficiency ◽  
Transmission Electron ◽  
Reductive Atmosphere

W18O49 nanorods photocatalyst was successfully synthesized by a facile pyrolyzing ammonium metatungstate in a reductive atmosphere of H2 (5 vol %)/Ar. The synthesized W18O49 nanorods were characterized by X-ray diffraction (XRD), Raman spectrum, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and ultraviolet-visible (UV-Vis) absorption spectroscopy. The results show that W18O49 nanorods are about 190 nm in diameter and around 4.8 μm in length, and they possess the band-gap energy of 2.32 eV. Moreover the photocatalytic activity of W18O49 nanorods was evaluated by degrading methylene blue (MB) under visible light irradiation. The result illustrates that the W18O49 nanorods have a photodegradation efficiency of 60% for MB under the irradiation of xenon lamp (250 W, λ > 420 nm) for 2 h.

Synthesis and Characterization of Mn2+ Doped ZnS Using Reverse Miceller Method

2014 ◽  
Vol 970 ◽  
pp. 283-287
Author(s):  
Rahizana Mohd Ibrahim ◽  
Markom Masturah ◽  
Huda Abdullah
Keyword(s):  
Quantum Confinement ◽  
Quantum Confinement Effect ◽  
Blue Shift ◽  
Band Gap Energy ◽  
Confinement Effect ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Size Of Particles ◽  
Absorbance Spectra

In this work we synthesized the monodisperse of Zn1-xMnxS with x =0.00,0.02,0.04,0.06,0.08 and 0.10 nanoparticles by reverse micelle method using sodium bis (2-ethylhexyl) sulfosuccinate (AOT) as surfactant. The prepared particles were characterized using UV-Visible Spectroscopy, X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and Photoluminescence (PL) for size, morphology and optical of the samples .UV-vis absorbance spectra for all of the synthesized nanoparticles show the maximum absorption for all samples is observed at range 210 - 300 nm . The absorption edge shifted to lower wavelengths when doping with ion Mn as per UV-Vis spectroscopy. The band gap energy values were increase from 4.50eV to 4.90 eV. This blue shift is attributed to the quantum confinement effect. The size of particles is found to be 3-5nm range. The Mn2+ doped ZnS nanoparticles using reverse micelles method shows the enhance of PL intensity results in monodisperse nanoparticles. Keywords: Nanoparticles; UV-vis absorbance spectra; quantum confinement effect; photoluminescence.

scholarly journals Controlled Synthesis of CuS and Cu9S5 and Their Application in the Photocatalytic Mineralization of Tetracycline

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 899
Author(s):  
Murendeni P. Ravele ◽  
Opeyemi A. Oyewo ◽  
Damian C. Onwudiwe
Keyword(s):  
Electron Microscopy ◽  
Visible Light ◽  
Blue Shift ◽  
X Ray Diffraction ◽  
X Ray ◽  
Copper Sulfides ◽  
Transmission Electron ◽  
Single Source Precursor ◽  
Pure Phase ◽  
Pure Phases

Pure-phase Cu2−xS (x = 1, 0.2) nanoparticles have been synthesized by the thermal decomposition of copper(II) dithiocarbamate as a single-source precursor in oleylamine as a capping agent. The compositions of the Cu2−xS nanocrystals varied from CuS (covellite) through the mixture of phases (CuS and Cu7.2S4) to Cu9S5 (digenite) by simply varying the temperature of synthesis. The crystallinity and morphology of the copper sulfides were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), which showed pure phases at low (120 °C) and high (220 °C) temperatures and a mixture of phases at intermediate temperatures (150 and 180 °C). Covellite was of a spherical morphology, while digenite was rod shaped. The optical properties of these nanocrystals were characterized by UV−vis–NIR and photoluminescence spectroscopies. Both samples had very similar absorption spectra but distinguishable fluorescence properties and exhibited a blue shift in their band gap energies compared to bulk Cu2−xS. The pure phases were used as catalysts for the photocatalytic degradation of tetracycline (TC) under visible-light irradiation. The results demonstrated that the photocatalytic activity of the digenite phase exhibited higher catalytic degradation of 98.5% compared to the covellite phase, which showed 88% degradation within the 120 min reaction time using 80 mg of the catalysts. The higher degradation efficiency achieved with the digenite phase was attributed to its higher absorption of the visible light compared to covellite.

scholarly journals V2O3/C composite fabricated by carboxylic acid-assisted sol–gel synthesis as anode material for lithium-ion batteries

2021 ◽  
Author(s):  
G. S. Zakharova ◽  
E. Thauer ◽  
A. N. Enyashin ◽  
L. F. Deeg ◽  
Q. Zhu ◽  
...  
Keyword(s):  
Electrochemical Performance ◽  
Lithium Ion Batteries ◽  
Sol Gel ◽  
Carbon Sources ◽  
Lithium Ion ◽  
X Ray Diffraction ◽  
Electron Microscopies ◽  
Transmission Electron ◽  
Battery Electrode ◽  
Sol Gel Synthesis

AbstractThe potential battery electrode material V2O3/C has been prepared using a sol–gel thermolysis technique, employing vanadyl hydroxide as precursor and different organic acids as both chelating agents and carbon sources. Composition and morphology of resultant materials were characterized by X-ray diffraction, Raman spectroscopy, scanning and transmission electron microscopies, physical sorption, and elemental analysis. Stability and electronic properties of model composites with chemically and physically integrated carbon were studied by means of quantum-chemical calculations. All fabricated composites are hierarchically structured and consist of carbon-covered microparticles assembled of polyhedral V2O3 nanograins with intrusions of amorphous carbon at the grain boundaries. Such V2O3/C phase separation is thermodynamically favored while formation of vanadium (oxy)carbides or heavily doped V2O3 is highly unlikely. When used as anode for lithium-ion batteries, the nanocomposite V2O3/C fabricated with citric acid exhibits superior electrochemical performance with an excellent cycle stability and a specific charge capacity of 335 mAh g−1 in cycle 95 at 100 mA g−1. We also find that the used carbon source has only minor effects on the materials’ electrochemical performance.

Immobilization of K7PW11O39 on ZrO2 Nanofiber: Ultra-deep Desulfurization Based in Extraction Catalytic Oxidation Desulfurization System

2021 ◽  
Vol 72 (3) ◽  
pp. 89-101
Author(s):  
Guowei Zeng ◽  
Guihong Wu ◽  
Zhihui Wang ◽  
Xiaonan Li ◽  
Jie Yang ◽  
...  
Keyword(s):  
Catalytic Oxidation ◽  
Catalytic Mechanism ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Thermo Gravimetric ◽  
Transmission Electron ◽  
Deep Desulfurization ◽  
Thermo Gravimetric Analyzer ◽  
Ft Ir ◽  
Model Oil

In this work, K7PW11O39 (abbreviated as PW11) was immobilized on ZrO2 nanofibers and used as an efficient recyclable catalyst in extraction catalytic oxidation desulfurization system (ECODS).The 500 ppm DBT model oil(5mL) can desulphurize completely within 20 min with the catalytic conditions of 50��, 0.010 g 50 wt%- CTAB�C PW11�CZrO2 nanofibers and O/S molar ratio H2O2/DBT molar ratio�� was 2:1. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and thermo gravimetric analyzer (TGA). The results indicated the PW11�CZrO2 nanofibers were synthesized successfully and the possible catalytic mechanism is also revealed.

scholarly journals Magnetic PbFe12O19-TiO2 nanocomposites and their photocatalytic performance in the removal of toxic pollutants

2018 ◽  
Vol 41 (3-4) ◽  
pp. 53-62 ◽  
Author(s):  
Behnaz Lahijani ◽  
Kambiz Hedayati ◽  
Mojtaba Goodarzi
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Performance ◽  
Sol Gel ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Photocatalytic Effect ◽  
Transmission Electron ◽  
Ultraviolet Light Irradiation

Abstract In this work, the PbFe12O19 nanoparticles were prepared by the simple and optimized precipitation method with different organic surfactants and capping agents. In the next step, the TiO2 nanoparticles were synthesized using the sol-gel method. At the final step, the PbFe12O19-TiO2 nanocomposites were prepared via the sol-gel method. The effect of the precipitating agent on the morphology and particle size of the products was investigated. The prepared products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The results obtained by the vibrating sample magnetometer show the magnetic properties of the ferrite nanostructures. The photocatalytic effect of the PbFe12O19-TiO2 nanocomposite on the elimination of the azo dyes (acid black, acid violet and acid blue) under ultraviolet light irradiation was evaluated. The results indicate that the prepared nanocomposites have acceptable magnetic and photocatalytic performance.

scholarly journals Synthesis, Physical Properties and Enzymatic Degradation of Biodegradable Nanocomposites Fabricated Using Poly(Butylene Carbonate-Co-Terephthalate) and Organically Modified Layered Zinc Phenylphosphonate

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2149
Author(s):  
Li-Ying Tseng ◽  
Erh-Chiang Chen ◽  
Jie-Mao Wang ◽  
Tzong-Ming Wu
Keyword(s):  
Nmr Spectra ◽  
Enzymatic Degradation ◽  
Molar Ratio ◽  
Wide Angle ◽  
Mixing Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Organically Modified ◽  
Biodegradable Nanocomposites

A new biodegradable aliphatic-aromatic poly (butylene carbonate-co-terephthalate) (PBCT-85) with the molar ratio [BC]/[BT] = 85/15, successfully synthesized through transesterification and polycondensation processes, was identified using 1H-NMR spectra. Various weight ratios of PBCT/organically modified layered zinc phenylphosphonate (m-PPZn) nanocomposites were manufactured using the solution mixing process. Wide-angle X-ray diffraction and transmission electron microscopy were used to examine the morphology of PBCT-85/m-PPZn nanocomposites. Both results exhibited that the stacking layers of m-PPZn were intercalated into the PBCT-85 polymer matrix. The additional m-PPZn into PBCT-85 copolymer matrix significantly enhanced the storage modulus at −70 °C, as compared to that of neat PBCT-85. The lipase from Pseudomonas sp. was used to investigate the enzymatic degradation of PBCT-85/m-PPZn nanocomposites. The weight loss decreased as the loading of m-PPZn increased, indicating that the existence of m-PPZn inhibits the degradation of the PBCT-85 copolymers. This result might be attributed to the higher degree of contact angle for PBCT-85/m-PPZn nanocomposites. The PBCT-85/m-PPZn composites approved by MTT assay are appropriate for cell growth and might have potential in the application of biomedical materials.

scholarly journals Synthesis of Co3O4 Nano Aggregates by Co-precipitation Method and its Catalytic and Fuel Additive Applications

2019 ◽  
Vol 17 (1) ◽  
pp. 865-873 ◽  
Author(s):  
Muhammad Ramzan Saeed Ashraf Janjua
Keyword(s):  
Electron Microscopy ◽  
Precipitation Method ◽  
Fuel Additive ◽  
X Ray Diffraction ◽  
Efficient Catalyst ◽  
Calcination Process ◽  
Electron Microscopies ◽  
Transmission Electron ◽  
Co Precipitation ◽  
Individual Particles

AbstractThe nano aggregates of cobalt oxide (Co3O4) are synthesized successfully by adopting simple a co precipitation approach. The product obtained was further subjected to the calcination process that not only changed it morphology but also reduces the size of individual particles of aggregates. The prepared nano aggregates are subjected to different characterization techniques such as electron microscopies (scanning electron microscopy and transmission electron microscopy) and X-ray diffraction and results obtained by these instruments are analyzed by different software. The characterization results show that, although the arrangement of particles is compact, several intrinsic spaces and small holes/ pores can also be seen in any aggregate of the product. The as synthesized product is further tested for catalytic properties in thermal decomposition of ammonium perchlorate and proved to be an efficient catalyst.

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