SYNTHESIS OF NOVEL NANOSTRUCTURED LANTHANUM COBALT FERRITE MIXED METAL OXIDES BY SOL–GEL

2013 ◽  
Vol 12 (01) ◽  
pp. 1350007
Author(s):  
V. MARY TERESITA ◽  
V. JESEENTHARANI ◽  
B. AVILA JOSEPHINE ◽  
S. ARUL ANTONY
Keyword(s):  
Metal Oxides ◽  
Sol Gel ◽  
Chemical Properties ◽  
Mixed Metal Oxides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mixed Metal ◽  
Size Dependent ◽  
Ft Ir ◽  
And Chemical Properties

Properties of nanoscale materials are very interesting and these are either comparable to or superior to those of bulk. These materials are interesting due to their exciting size dependent optical, electronic, magnetic, thermal, mechanical and chemical properties. Different mole ratios of nanostructured mixed metal oxides of LaCo x Fe 1-x O 3-δ (x = 0 to 1) were prepared by the sol–gel method by varying the mole ratios of iron and cobalt substrates. The compounds were sintered for 700°C in the tubular furnace for 8 h. The purity of the compounds was analyzed by TG-DTA. The compounds were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM) studies were employed to study the structural phases, vibrational frequencies, surface morphology of the highest humidity sensing compounds.

scholarly journals Characterization of Mixed-Metal Oxides Using Synchrotron-Based Time-Resolved x-ray Diffraction and x-ray Absorption Spectroscopy

1999 ◽  
Vol 590 ◽  
Author(s):  
José A. Rodriguez ◽  
Jonathan C. Hanson ◽  
Joaquín L. Brito ◽  
Amitesh Maiti
Keyword(s):  
Metal Oxides ◽  
Density Functional ◽  
Chemical Properties ◽  
Local Symmetry ◽  
Mixed Metal Oxides ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Mixed Metal ◽  
X Ray Absorption

ABSTRACTExperiments are described showing the utility of synchrotron-based time-resolved x-ray diffraction (TR-XRD) and x-ray absorption near-edge spectroscopy (XANES) for characterizing the physical and chemical properties of mixed-metal oxides that contain Mo and a second transition metal (Fe, Co or Ni). TR-XRD was used to study the transformations that occur during the heating of a FeMoO4/Fe2(MoO4)3 mixture and the α⇒β phase transitions in CoMoO4 and NiMoO4. The Mo LII- and O K-edges in XANES are very useful for probing the local symmetry of Mo atoms in mixed-metal oxides. The results of XANES and density-functional calculations (DMo13, DFT-GGA) show large changes in the splitting of the empty Mo 4d levels when going from tetrahedral to octahedral coordinations. XANES is very useful for studying the reaction of H2, H2S and SO2 with the mixed-metal oxides. Measurements at the S K-edge allow a clear identification of S, SO2, SO3 or SO4 on the oxide surfaces. Changes in the oxidation state of molybdenum produce substantial shifts in the position of the Mo LII- and MIII-edges.

Characterization of Y/TiO2 Nanoparticles and their Reactivity for CO2 Photoreduction

2011 ◽  
Vol 55-57 ◽  
pp. 1506-1510 ◽  
Author(s):  
Jing Wei ◽  
Xin Tan ◽  
Tao Yu ◽  
Lin Zhao
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Illumination ◽  
Transmission Electron ◽  
And Chemical Properties

A series of Y/TiO2nanoparticles (NPs) were synthesized via sol-gel method. The crystal structures, morphologies and chemical properties were characterized using X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). We investigated the effects of different doping amounts of Y on the reaction of CO2photoreduction. The results shown that 0.1 wt.%Y/TiO2(0.1YT) performed the highest photocatalytic activity, which yielded 384.62 µmol/g∙cat. formaldehyde after 6 h of UV illumination.

scholarly journals Sol-Gel Synthesized Semiconductor Oxides in Photocatalytic Degradation of Phenol

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Maria K. Cherepivska ◽  
Roman V. Prihod’ko
Keyword(s):  
Photocatalytic Degradation ◽  
Sol Gel ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Semiconductor Oxides ◽  
Titanium Dioxide Sample ◽  
Vis Spectroscopy ◽  
Physical And Chemical ◽  
And Chemical Properties

Effectiveness of photocatalytic degradation of phenol in aqueous solution using semiconductor oxides (SO) prepared by a sol-gel method was examined. The physical and chemical properties of synthesized catalysts were investigated by X-ray diffraction (XRD), diffuse reflectance UV-Vis spectroscopy (DRS), and N2-adsorption measurements. The optimal conditions of the photocatalytic degradation of phenol using prepared titanium dioxide sample were defined.

scholarly journals The behavior of mixed-metal oxides: Physical and chemical properties of bulk Ce1−xTbxO2 and nanoparticles of Ce1−xTbxOy

2004 ◽  
Vol 121 (11) ◽  
pp. 5434-5444 ◽  
Author(s):  
Xianqin Wang ◽  
Jonathan C. Hanson ◽  
Gang Liu ◽  
José A. Rodriguez ◽  
Ana Iglesias-Juez ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Chemical Properties ◽  
Mixed Metal Oxides ◽  
Physical And Chemical Properties ◽  
Mixed Metal ◽  
Physical And Chemical ◽  
And Chemical Properties

Studies on the Behavior of Mixed-Metal Oxides:  Structural, Electronic, and Chemical Properties of β-FeMoO4

2000 ◽  
Vol 104 (34) ◽  
pp. 8145-8152 ◽  
Author(s):  
José A. Rodriguez ◽  
Jonathan C. Hanson ◽  
Sanjay Chaturvedi ◽  
Amitesh Maiti ◽  
Joaquín L. Brito
Keyword(s):  
Metal Oxides ◽  
Chemical Properties ◽  
Mixed Metal Oxides ◽  
Mixed Metal ◽  
And Chemical Properties

Electronic and chemical properties of mixed-metal oxides: Adsorption and reaction of NO on SrTiO3(100)

2003 ◽  
Vol 118 (14) ◽  
pp. 6562-6571 ◽  
Author(s):  
J. A. Rodriguez ◽  
S. Azad ◽  
L.-Q. Wang ◽  
J. Garcı́a ◽  
A. Etxeberria ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Chemical Properties ◽  
Mixed Metal Oxides ◽  
Mixed Metal ◽  
And Chemical Properties

Novel SrO-CaO Mixed Metal Oxides Catalyst for Ultrasonic-Assisted Transesterification of Jatropha Oil into Biodiesel

2017 ◽  
Vol 70 (3) ◽  
pp. 258 ◽  
Author(s):  
Syed Danish Ali ◽  
Isma Noreen Javed ◽  
Usman Ali Rana ◽  
Muhammad Faizan Nazar ◽  
Waqas Ahmed ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Fatty Acid Methyl Esters ◽  
Methyl Esters ◽  
Mixed Metal Oxides ◽  
Jatropha Oil ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mixed Metal ◽  
Acid Methyl ◽  
Ultrasonic Assisted

The transesterification of edible and non-edible oils to produce biodiesel is traditionally carried out using homogeneous catalysts (such as NaOH, KOH, and H2SO4). However, these homogenous catalysts often suffer from multiple drawbacks including their corrosive nature and solubility in the reaction mixture, and high costs associated with their recovery. Recent studies have shown that heterogeneous catalysts based on mixed metal oxides have the potential to address the issues associated with conventional homogeneous catalysts, thereby emerging as an efficient class of catalyst materials for biodiesel production. In this study, we describe a heterogeneous strontium oxide/calcium oxide (SrO-CaO) mixed metal oxides catalyst, which displays remarkable efficiency towards the ultrasonic-assisted transesterification of Jatropha oil into biodiesel. The SrO-CaO heterogeneous catalyst was prepared by the wet impregnation method, and the structural morphology of the as-synthesized catalyst was revealed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and nitrogen sorption technique coupled with the Brunauer–Emmett–Teller and Barrett–Joyner–Halenda methods. The X-ray diffraction analysis confirmed the cubic structure of the SrO-CaO catalyst. The catalytic activity of this newly developed catalyst showed a high percentage conversion of triglyceride into the corresponding fatty acid methyl esters (98.19 %) as confirmed by 1H NMR spectroscopy. The chemical composition of the prepared biodiesel by this ultrasonic-assisted transesterification process was determined by the gas chromatography–mass spectrometry. Five major fatty acid methyl esters were identified, of which 9-octadecenoic acid methyl ester was obtained with the highest percentage ~38.22 %. Hence, the study reveals that the SrO-CaO catalyst exhibits high efficiency towards converting Jatropha oil into biodiesel by ultrasonic-assisted transesterification.

Sign in / Sign up

Export Citation Format

Share Document