Synthesis and x-ray diffraction characterization of nanocrystalline ZnO obtained by Pechini method

Spinel-perovskite multiferroics of NiFe2O4/BiFeO3 nanoparticles were prepared by modified Pechini method. The structure and morphology of the composites were examined by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the composites consisted of spinel NiFe2O4 and perovskite BiFeO3 after annealed at 700°C for 2h, and the particle size ranges from 40 to 100nm. VSM and ME results indicated that the nanocomposites exhibited both tuning magnetic properties and a ME effect. The ME effect of the nanocomposites strongly depended on the magnetic bias and magnetic field frequency.

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PECHINI SYNTHESIS AND CHARACTERIZATION OF Eu3+ DOPED ZnCo2O4 SPINELS

Periódico Tchê Química ◽

10.52571/ptq.v2.n03.2005.janeiro/4_pgs_24_29.pdf ◽

2005 ◽

Vol 03 (2) ◽

pp. 24-29

Author(s):

P.M. PIMENTEL ◽

A.M.G. PEDROSA ◽

H.K.S. SOUZA ◽

C.N.S. JÚNIOR ◽

R.C.A. PINTO ◽

...

Keyword(s):

Spinel Structure ◽

Pechini Method ◽

Synthesis Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Spinel Oxides ◽

Diffraction Patterns ◽

Pechini Synthesis ◽

Spinel Structures

Spinel oxides with the composition ZnCo2O4 and ZnCo2O4:Eu3+ have been synthesized by the Pechini method and characterized by X-ray diffraction, infrared spectroscopy, thermal analysis and scanning electron microscopy. IR spectroscopy revealed the presence of n1 and n2 bands, typical of spinel structures. The formation of monophase cubic spinel structure was confirmed by X-ray diffraction patterns. Extra lines corresponding to other phase has been observed in the powders calcined at 900 ºC. The results showed the extremely lower synthesis temperature than those presents in conventional methods.

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Structural and morphological characterization of rare earth modified lead titanate

Cerâmica ◽

10.1590/s0366-69132007000400017 ◽

2007 ◽

Vol 53 (328) ◽

pp. 422-447

Author(s):

F. C. D. Lemos ◽

D. M. A. Melo ◽

P. S. de Lima ◽

C. A. Paskocimas ◽

E. Longo ◽

...

Keyword(s):

Rare Earth ◽

Lead Titanate ◽

Pechini Method ◽

Morphological Characterization ◽

X Ray Diffraction ◽

X Ray ◽

Different Temperatures ◽

Crystallite Sizes ◽

Modifier Cation

Rare earth modified lead titanate powders Pb1-xRExTiO3 (REPT), x = 0.01, 0.05, 0.07 and RE = Yb, Y, were prepared by the Pechini method. The materials were calcined under flowing oxygen at different temperatures from 300 to 700 ºC. Nanostructured REPT were investigated using X-ray diffraction, scanning electron microscopy and surface area analysis (BET). The results suggest that the modifier cation incorporated into the system has notable influence in the microstructure and a notable decrease in the crystallite sizes.

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Characterization of new solid solution phases in (Y,Ca)(Cr,Co)O3 system

Powder Diffraction ◽

10.1017/s0885715600014287 ◽

1995 ◽

Vol 10 (1) ◽

pp. 40-43 ◽

Cited By ~ 1

Author(s):

Cem Basceri ◽

A. Cuneyt Tas ◽

Muharrem Timucin

Keyword(s):

Solid Solution ◽

Powder Diffraction ◽

Pechini Method ◽

X Ray Diffraction ◽

X Ray ◽

Modified Pechini Method ◽

Diffraction Patterns

New solid solution phases in the (Y,Ca)(Cr,Co)O3 system have been synthesized and characterized by powder X-ray diffraction. The selected compositions in this system were prepared by the modified Pechini method. Powder-diffraction patterns were prepared.

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Synthesis and Characterization of TiO2 Nanoparticles by the Method Pechini

Materials Science Forum ◽

10.4028/www.scientific.net/msf.660-661.385 ◽

2010 ◽

Vol 660-661 ◽

pp. 385-390 ◽

Cited By ~ 6

Author(s):

João Victor Marques Zoccal ◽

Fábio Oliveira Arouca ◽

José Antônio Silveira Gonçalves

Keyword(s):

Pechini Method ◽

Titanium Isopropoxide ◽

Differential Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Bet Method ◽

Infrared Method ◽

Titanium Citrate ◽

Nanosized Tio2

In recent years, scientific research showed an increasing interest in the field of nanotechnology, resulting in several techniques for the production of nanoparticles, such as methods of chemical synthesis. Among the various existing methods, the Pechini method has been used to obtain nanoparticles of titanium dioxide (TiO2). Thus, this work aims to synthesize and characterize nanoparticles of TiO2 obtained by this method. The technique constitutes in the reaction between citric acid with titanium isopropoxide, resulting as the product the titanium citrate. With the addition of the ethylene glycol polymerization occurs, resulting in a polymeric resin. At the end of the process, the resin is calcined to remove organic matter, creating nanoparticles of TiO2. The resulting powders were characterized by thermogravimetric analysis (TGA) and thermal differential analysis (DTA), X-ray diffraction, absorption spectrophotometry in the infrared, method of adsorption nitrogen / helium (BET method) and scanning electron microscopy. The results obtained in the characterization techniques showed that the Pechini method is promising in obtaining nanosized TiO2.

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Evaluation of Calcined Temperature on the Structural and Morphological Characterization of TiO2 Doped with Zr Nanopowders Obtained by the Pechini Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.1393 ◽

2012 ◽

Vol 727-728 ◽

pp. 1393-1397 ◽

Cited By ~ 2

Author(s):

M.A. Ribeiro ◽

Laédna Souto Neiva ◽

Ruth Herta Goldsmith Aliaga Kiminami ◽

J.B.L. de Oliveira ◽

L. Gama

Keyword(s):

Pechini Method ◽

Anatase Phase ◽

Morphological Characteristics ◽

Morphological Characterization ◽

Catalytic Reactions ◽

X Ray Diffraction ◽

X Ray ◽

20 Nm ◽

Calcined Temperature

Because of the unique properties that the system TiO2-ZrO2 has, this system has attracted great interest in catalytic circles. In general, the TiO2-ZrO2 oxides composites have a greater surface area and a stronger acidity when compared to the single oxide and they are used as catalysts supports for many catalytic reactions. This work is to evaluate the effect of calcined temperature in structural and morphological characteristics of Ti1-xZrxO2nanopowders obtained by Pechini method. For this study, the doping value was 0.25 moles of Zr. The powders were calcined at temperature of 500 to 900°C for one hour. The powders were characterized by XRD, SEM and BET. The X-ray diffraction showed that the powders present a TiO2anatase phase and another of ZrO2tetragonal. The crystallite size ranged from 4.8 to 14.6 nm for the temperature of 500 to 900°C, respectively. The analysis of scanning electron microscopy showed soft homogeneous agglomerates with particles around 100 nm. The main particles sizes by BET were ranged from 10 to 20 nm, showing that the synthesis is effective to obtain nanometric powders.

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Characterization of nickel doped Zn7Sb2O12 spinel phase using Rietveld refinement

Powder Diffraction ◽

10.1154/1.1572486 ◽

2003 ◽

Vol 18 (3) ◽

pp. 219-223 ◽

Cited By ~ 3

Author(s):

L. Gama ◽

C. O. Paiva-Santos ◽

C. Vila ◽

P. N. Lisboa-Filho ◽

E. Longo

Keyword(s):

Crystal Structure ◽

Rietveld Refinement ◽

Spinel Phase ◽

Pechini Method ◽

Polymeric Precursor ◽

X Ray Diffraction ◽

Inverse Spinel ◽

Precursor Method ◽

X Ray

Zn7Sb2O12 is known to adopt an inverse spinel crystal structure, in which Zn2+ occupies the eight tetrahedral positions and Sb5+ and Zn2+ randomly occupy the 16 octahedral positions. Samples of Zn7−xNixSb2O12 (x=0, 1, 2, 3, and 4) were synthesized using a modified polymeric precursor method, known as the Pechini method. The crystal structure of the powders was characterized by Rietveld refinement with X-ray diffraction data. The results show that for x=0, 1, and 2 Ni substitutes for Zn2+ in the octahedral sites, and that for x=3 and 4 it is assumed that Ni2+ replaces Zn2+ ions in both the octahedral and tetrahedral positions. It is also observed for x=3 and 4 the formation of two spinel phases.

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Preparation and Characterization of Pb(Zr,Ti)O3 Obtained by the Pechini Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.912.97 ◽

2018 ◽

Vol 912 ◽

pp. 97-101

Author(s):

Raphael Cons Andrades ◽

Antônio Hortencio Munhoz Jr. ◽

Leila Figueiredo de Miranda ◽

Renata Ayres Rocha

Keyword(s):

Lead Zirconate Titanate ◽

Pechini Method ◽

Lead Nitrate ◽

Lead Zirconate ◽

Polymeric Precursor ◽

X Ray Diffraction ◽

Zirconyl Nitrate ◽

X Ray ◽

Scanning Electron

The aim of this work was to synthesize lead zirconate titanate, Pb(Zr0.52Ti0.48)O3 (PZT) via Pechini method, to characterize the polymeric precursor through differential thermal analysis and thermogravimetric analysis, as well as to characterize the PZT powder through x-ray diffraction and scanning electron microscopy with energy-dispersive spectroscopy. In this work, the metallic precursors used during the PZT synthesis were titanium IV isopropoxide, zirconyl nitrate and lead nitrate; citric acid and ethylene glycol were used as chelating and polymerizing agents, respectively. The polymeric precursor was calcined at 800°C for two hours in a muffle oven. The main results showed that the polymeric precursor undergoes decomposition at approximately 316°C and PZT is crystallized around 722°C. It was confirmed that the PZT powder has chemical composition in the morphotropic phase boundary and its morphology consists of agglomerates of particles. Finally, it was proved that the PZT powder is crystalline, with the predominance of the tetragonal phase.

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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High Resolution Replication of Organoclay Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055126 ◽

1982 ◽

Vol 40 ◽

pp. 576-577

Author(s):

W. W. Barker ◽

W. E. Rigsby ◽

V. J. Hurst ◽

W. J. Humphreys

Keyword(s):

Clay Mineral ◽

Organic Molecule ◽

Organic Molecules ◽

X Ray Diffraction ◽

Xrd Pattern ◽

X Ray ◽

Naturally Occurring ◽

Silicate Layers ◽

Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

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