Effects of V2O5 on the synthesis of Ba2Ti9O20 powders

Phase-pure Ba2Ti9O20 powders were made by doping 3 wt% of V2O5 to a Ba:Ti = 2:9 molar composition, and the effects of the dopant on the phase formation were investigated. The study shows that BaTiO3, BaTi2O5, and BaTi4O9 were the intermediate phases before the formation of Ba2Ti9O20 for samples with or without V2O5. However, with V2O5 doping, the temperature at which Ba2Ti9O20 occurred were lowered from 1150 to 1050 °C and single phase Ba2Ti9O20 powders was easily obtained at 1150 °C for 2 h. Microstructure of the powders was examined by field emission scanning electron microscopy. No evidence of V2O5–Ba2Ti9O20 solid-solution was found by x-ray diffraction and energy-dispersive spectroscopy. The benefit of V2O5 to facilitate the Ba2Ti9O20 synthesis is most probably due to a vanadium-containing eutectic liquid phase which accelerates the migration of reactant species.

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Synthesis of Ti3Si0.4Al0.8C1.8 Solid Solution

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.995 ◽

2008 ◽

Vol 368-372 ◽

pp. 995-997

Author(s):

Cui Wei Li ◽

Hong Xiang Zhai ◽

Yang Zhou ◽

Shi Bo Li ◽

Zhi Li Zhang

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Scanning Electron Microscopy ◽

Single Phase ◽

Lattice Parameters ◽

Molar Ratio ◽

X Ray Diffraction ◽

Powder Mixtures ◽

X Ray ◽

Scanning Electron

In this study, free Ti/Si/Al/C powder mixtures with molar ratio of 3:0.4:0.8:1.8 were heated in Argon with various schedules, in order to reveal the possibility for the synthesis of Ti3Si0.4Al0.8C1.8 solid solution powder. X-ray diffraction (XRD) was used for the evaluation of phase identities of the powder after different treatments. Scanning electron microscopy (SEM) was used to observe the morphology of the Ti3Si0.4Al0.8C1.8 solid solution. XRD results showed that predominantly single phase samples of Ti3Si0.4Al0.8C1.8 was prepared after heating at 1400oC for 5 min in Argon and the lattice parameters of Ti3Si0.4Al0.8C1.8 lay between those of Ti3SiC2 and Ti3AlC2.

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Influence of Annealing Time on Microstructure of Ni-W Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.747-748.613 ◽

2013 ◽

Vol 747-748 ◽

pp. 613-618

Author(s):

Qiao Zhang ◽

Shu Hua Liang ◽

Chen Zhang ◽

Jun Tao Zou

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Grain Size ◽

Grain Boundaries ◽

Annealing Time ◽

Single Phase ◽

X Ray Diffraction ◽

X Ray ◽

Average Grain Size ◽

Scanning Electron

The as-cast Ni-W alloys with 15wt%W, 25wt%W and 30wt%W were annealed in hydrogen at 1100. The effect of the annealing time on the microstructure of Ni-W alloys was studied, and the phase constituents and microstructure of annealed Ni-W alloys were characterized by the X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that no any phase changed for Ni-15%W, Ni-25%W and Ni-30%W alloys annealed for 60 min, 90 min and 150 min, which were still consisted of single-phase Ni (W) solid solution. However, microstructure had a significant change after annealing. With increase of annealing time, the microstructure of Ni-15%W alloy became more uniform after annealing for 90 min, and the average grain size was 95μm, whereas the grain size of Ni-15%W alloy increased significantly after annealing for 150 min. For Ni-25%W and Ni-30%W, there was no obvious change on the grain size with increase of annealing time, and the amount of oxides at grain boundaries gradually reduced. After annealing for 150 min, the impurities at grain boundaries almost disappeared. Subsequently, the annealing at 1100 for 150 min was beneficial for the desired microstructure of Ni-25%W and Ni-30%W alloys.

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Crystal Structure of BiFeO3 Synthesized Using the Hydrothermal Processing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.602-603.947 ◽

2014 ◽

Vol 602-603 ◽

pp. 947-950

Author(s):

Zhen Wang ◽

Hai Yan Chen ◽

Lin Qiang Gao ◽

Xin Zou

Keyword(s):

Crystal Structure ◽

Electron Microscopy ◽

Thermal Analysis ◽

Scanning Electron Microscopy ◽

Single Phase ◽

Hydrothermal Processing ◽

Optimal Conditions ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

BiFeO3 nanoparticles were successfully synthesized by a hydrothermal method by a mineralizer (KNO3). Structural characterization was performed by thermal analysis, powder X-ray diffraction (XRD) and scanning electron microscopy (TEM).The results showed that the products were perovskite structure BiFeO3 powders. Optimal conditions for the synthesis of single-phase BiFeO3 ceramics were obtained.

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Microwave-Assisted Preparation of Cu2O Octahedral Microcrystals

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.746 ◽

2011 ◽

Vol 284-286 ◽

pp. 746-749

Author(s):

Chong Hai Deng ◽

Han Mei Hu ◽

Ming Di Yang

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Scanning Electron Microscopy ◽

Growth Mechanism ◽

X Ray Diffraction ◽

Chemical Route ◽

X Ray ◽

Microwave Assisted ◽

Morphology And Structure ◽

Scanning Electron

In this paper, we reported a facile microwave-assisted green chemical route to prepare pure, uniform, and monodispersed Cu2O octahedron wrapped by the {111} faces by using glucose as a reducing agent. X-ray diffraction (XRD), energy dispersive X-ray spectrometry(EDX) and field emission scanning electron microscopy (FESEM) were used to characterize the as-synthesized products. It was found that the morphology and structure of Cu2O crystals were greatly affected by the concentration of NaOH. A solid-solution-solid growth mechanism was possibly proposed on the basis of the comparative experimental results.

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Microwave Synthesis of BaTiO3 from BaCO3 and TiO2

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.669 ◽

2007 ◽

Vol 336-338 ◽

pp. 669-671

Author(s):

Yan Yi Liu ◽

Wei Pan

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Microwave Oven ◽

X Ray Diffraction ◽

X Ray ◽

Batio3 Powder ◽

Domestic Microwave Oven ◽

Intermediate Phases ◽

Different Temperatures ◽

Scanning Electron

BaTiO3 powder was synthesized from BaCO3 and TiO2 using a domestic microwave oven. The samples were synthesized under different temperatures with various holding times. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to examine the phase compositions and morphologies of the result samples. The main phase obtained at 950°C was BaTiO3, and the intermediate phases Ba2TiO4 and Ba4TiO9 were also detected. The pure, well-crystallized BaTiO3 powder could be obtained at 1050°C within 10 minutes and the particle size ranged from 300~500nm. In comparison with conventional synthesis, faster speed and finer grains could be achieved through microwave heating.

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Carbothermal Synthesis of Cr3C2-WC-Ni Nanocomposite Powders

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.661.3 ◽

2013 ◽

Vol 661 ◽

pp. 3-6 ◽

Cited By ~ 2

Author(s):

Yong Zhong Jin ◽

Fa Ming Ye ◽

Xian Guang Zeng ◽

Rui Song Yang

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Scanning Electron Microscopy ◽

Carbothermal Reduction ◽

X Ray Diffraction ◽

X Ray ◽

Carbothermal Synthesis ◽

Unit Cells ◽

Nanocomposite Powders ◽

Scanning Electron

Cr3C2-WC-Ni nanocomposite powders with ~50-100 nm were synthesized from precursors by vacuum-aided carbothermal reduction at only 750 °C for 2 h. The phase composition and microstructure of the synthesized products were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The present study shows that Cr3C2-WC-Ni nanocomposite powders contain two kinds of solid-solution phases, namely Ni and (Cr, W)3C2solid solution, respectively. WC and W2C phases do not appear inreaction products due to the dissolution of tungsten atoms into Ni and Cr3C2unit cells. Especially, there is a change of the crystalline structure for (Cr, W)3C2phase from 750 °C to 800 °C.

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Sintesis Senyawa Aurivillius Ca1-xBi3,5+xLa0,5Ti4-xMnxO15: Struktur dan Sifat Dielektrik

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.14.1.14476.143-151 ◽

2018 ◽

Vol 14 (1) ◽

pp. 143

Author(s):

Zulhadjri Zulhadjri ◽

Rini Ramadhani ◽

Aulia Arivin Billah ◽

Syukri Arief ◽

Emriadi Emriadi

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Single Phase ◽

Double Exchange ◽

Orthorhombic Symmetry ◽

X Ray Diffraction ◽

Aurivillius Phase ◽

X Ray ◽

Scanning Electron

Sintesis senyawa feroelektrik yang berbasis fasa Aurivillius berlapis empat (n = 4) yang didadah kation La3+ dan Mn3+, Ca1-xBi3,5+xLa0,5Ti4-xMnxO15 dengan x = 0, 0,2, 0,4, 0,6, 0,8, dan1 telah dilakukan dengan teknik lelehan garam. Karakterisasi produk dengan difraksi sinar-X (XRD) menunjukkan bahwa fasa tunggal Aurivillius ditunjukkan oleh sampel dengan x = 0, 0,2, 0,4, dan 0,6. Refinement struktur dengan teknik Le Bail diketahui bahwa senyawa Aurivillius yang terbentuk sesuai dengan simetri ortorombik dan grup ruang A21am. Analisis dengan Scanning Electron Microscopy (SEM) untuk semua sampel memperlihatkan morfologi sampel berupa lempengan yang merupakan ciri khas senyawa Aurivillius. Nilai konstanta dielektrik sampel dan konduktivitasnya mengalami kenaikan dengan meningkatnya x. Konduktivitas paling tinggi dimiliki oleh sampel x = 0,2 yang diperkirakan akibat adanya interaksi pertukaran ganda (double exchange) antara Mn3+ dan Mn4+.Synthesis of Aurivillius Compounds Ca1-xBi3,5 + xLa0,5Ti4-xMnxO15: Structure and Dielectric Properties. Synthesis of ferroelectric compounds based on a four-phase Aurivillius phase (n = 4) which is doped with La3+ and Mn3+ cations, Ca1-xBi3,5+xLa0,5Ti4-xMnxO15 with x = 0, 0.2, 0.4, 0.6, 0 , 8, and 1 were carried out by molten salts technique. Characterization of products using X-ray diffraction (XRD) revealed that the single phase Aurivillius was shown by the samples with x = 0, 0,2, 0,4, and 0,6. The results of refinement show that the Aurivillius phase formed has orthorhombic symmetry with A21am space group. Morphology analysis by scanning electron microscopy (SEM) for all samples shows the plate-like as the characteristic of Aurivillius compounds. The value of dielectric constant and conductivity of the samples increases as increase of x. The conductivity of x = 0.2 is the highest predicted due to the interaction of double exchange between Mn3+ and Mn4+.

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Investigation on the Structural Properties of a New Prepared 0.2PZS-0.8PLZT Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.856.197 ◽

2013 ◽

Vol 856 ◽

pp. 197-200

Author(s):

Adel Sakri ◽

Ahmed Boutarfaia

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Scanning Electron Microscopy ◽

Smart Materials ◽

Sintering Temperature ◽

Human Life ◽

Advanced Technology ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

View of the importance that has the development in the field of advanced technology transmission in human life, smart materials draws the attention of many researchers. In this contribution, we are interested in synthesizing a new smart material of the ceramic type based on Pb, Zr, Ti (PZT) doped La in the site A, and Sb, Zn in site B from a solid solution of pure oxides. The synthesized samples are thermally treated at 800°C. The techniques of x-ray diffraction (XRD) and SEM (scanning electron microscopy) are used to characterize the microstructure (the crystallographic phase), and the densities of the obtained samples were determined from their weights and volumes. The effect of sintering temperature on the microstructure properties was studied.

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Growth of CuInSe2 monograin powders with different compositions

MRS Proceedings ◽

10.1557/proc-865-f14.28 ◽

2005 ◽

Vol 865 ◽

Cited By ~ 1

Author(s):

Marit Kauk ◽

Mare Altosaar ◽

Jaan Raudoja ◽

Kristi Timmo ◽

Maarja Grossberg ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Concentration Ratio ◽

Single Phase ◽

Bulk Composition ◽

Photoluminescence Spectra ◽

X Ray Diffraction ◽

X Ray ◽

Dominant Peak ◽

Scanning Electron

AbstractCuInSe2 monograin powders (MGP) were synthesized from Cu-In alloys of different Cu/In concentration ratios and elemental Se in liquid phase of flux material in evacuated quartz ampoules. The surface morphology, phase structure, and composition of the powder crystals were analyzed by scanning electron microscopy, X-ray diffraction, and energy-dispersive X-ray analysis respectively. Bulk composition was analyzed polarographically. Photoluminescence spectra were measured at 9 K. It was found that the composition of MGP material (Cu/In concentration ratio) can be controlled by the concentration ratio of precursor Cu-In alloys. Single phase CuInSe2 growth is realisable between 0.7<Cu/In<1 at the growth temperature of 1000 K. Photoluminescence spectra of near-stoichiometric materials had one dominant peak at 0.93 eV, which is typical to In-rich CuInSe2. Samples with high In content exhibited two broad bands with peak positions at 0.86 and 0.93 eV.

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Microstructural and Dielectrical Properties for Ceramics and Thin Films of the xPbTiO3-(1−x)SrTiO3 Solid Solution

MRS Proceedings ◽

10.1557/proc-688-c7.34.1 ◽

2001 ◽

Vol 688 ◽

Cited By ~ 2

Author(s):

E. Martínez ◽

A. Fundora ◽

O. Blanco ◽

S. García ◽

E. Heredia ◽

...

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Scanning Electron Microscopy ◽

Dielectric Properties ◽

Integrated Circuit ◽

X Ray Diffraction ◽

X Ray ◽

Analysis Technique ◽

Dielectrical Properties ◽

Scanning Electron

AbstractSrTiO3 and PbTiO3 perovskites are combined to form the xPbTiO3-(1−x)SrTiO3 (PST) solid solution. The effect of the PbTiO3 content on the microstructural and dielectric properties is studied for different compositions (x=0.1,0.3,0.5,0.7, and 0.9). Microstructural features of the PST system are studied by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) techniques. Electrical properties are studied by the thermoelectric analysis technique at both fixed frequency and varying frequency to study the behavior of the dielectric constant and dielectric loss.Films of 0.5PbTiO3-0.5SrTiO3 (PST50) have been obtained by RF ion sputtering on different substrates. We investigate the relation between the crystalline structure and the dielectric properties of PST50 films deposited on different metallic films. Scanning Electron Microscopy (SEM) and X-Ray Diffraction were used for the structural analysis of the PST50/TiN/Si and PST50/RuO2/TiN /Si systems. The dielectric properties of the PST50 films were measured for TiN/PST50/TiN/Si, and RuO2/PST50/RuO2/TiN/Si capacitors and the results were correlated to the structure and composition. The charge storage capabilities of the PST50 films are evaluated for possible application in integrated circuit technology.

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