scholarly journals Growth of significantly low dimensional zinc orthotitanate (Zn2TiO4) nanoparticles by solid state reaction method

2018 ◽  
Vol 50 (1) ◽  
pp. 133-138 ◽  
Author(s):  
Lizina Khatua ◽  
Rudrashish Panda ◽  
Avanendra Singh ◽  
Arpan Nayak ◽  
Pravakar Satapathy ◽  
...  

In this work, the ZnO-TiO2 mixed phase nanoparticles were prepared by solid state reaction method by using ZnO and TiO2 powder as precursors. The X-ray diffraction pattern shows a dominant phase of Zinc Orthotitanate (Zn2TiO4). The average particle size (58?18 nm) calculated by the analysing FESEM data closely matches with the particle size calculated by Scherrer?s equation. The calculated average particle size is significantly smaller than the previously published results of nanoparticles, prepared by same method. In the Brunauer-Emmett-Teller (BET) study the specific surface area of the nanoparticles was found as 8.78 m2/g which is similar to the surface area reported in this material prepared by mechanochemical method. The method which we report is simpler and cost effective unlike the previous reported.

2009 ◽  
Vol 421-422 ◽  
pp. 247-250 ◽  
Author(s):  
Atthakorn Thongtha ◽  
Kritsana Angsukased ◽  
Theerachai Bongkarn

The effect of calcination (1000-1400 oC) and sintering temperatures (1400-1600 oC) on the phase formation and microstructure of barium strontium zirconate titanate [(Ba0.25Sr0.75)(Zr0.75Ti0.25)O3; BSZT] ceramics were investigated. BSZT powders were prepared by the solid-state reaction method. Higher calcination temperatures increased the percentage of the perovskite phase, but decreased the lattice parameter a of BSZT powders. The pure perovskite phase of BSZT powders was detected above the calcination temperature of 1350 oC. The microstructure of BSZT powders exhibited an almost-spherical morphology and had a porous agglomerated form. The average particle size and the average grain size of the ceramics were increased with the increase of calcination and sintering temperatures. The highest density of the samples was 5.42 g/cm3 which was obtained from ceramic sintered at 1550 oC for 2 h.


1990 ◽  
Vol 5 (10) ◽  
pp. 2056-2065 ◽  
Author(s):  
Nae-Lih Wu ◽  
Ta-Chin Wei ◽  
Shau-Y Hou ◽  
S-Yen Wong

The kinetics of the solid-state reaction Y2BaCuO5 + 3BaCuO2 + 2CuO ⇉ 2YBa2Cu3O6.5−x + xO2 was studied by using x-ray diffractometric and thermogravimetric analyses. Both analyses established that the reaction was well described by the kinetic equation: 1 − 3(1 − F)2/3 + 2(1 − F) = k0 exp(− E/RT)t, where F is the fractional conversion of a calcined powder, E is 520 kcal/molc and, for a rcactant mixture with an average particle size of 3 μm, k0 is 2.03 ⊠ 1092 min−1. An unreacted-core shrinking model was proposed to obtain the particle-size dependence of the reaction, and predicted that the pre-exponential constant k0 changed with reactant particle size by k0 = 2.03 ⊠ 1092(3/d)2 exp(4/d − 4/3), where d is the average reactant particle size in μm.


2020 ◽  
Vol 11 (3) ◽  
pp. 441-447
Author(s):  
Nanang Setiawan ◽  
◽  
Chung-Jen Tseng ◽  
Chin Tien Shen ◽  
ING Wardana ◽  
...  

The purpose of this study is to investigate the microstructure characteristics of the Ni1-xCux-BCZY anode and to analyze the carbon resistance by doping Cu into the Ni-BCZY anode. Ni1-xCux and BaCe0.7Zr0.1Y0.2O3-𝛿 (BCZY) powder were prepared by solid-state reaction with Ni1-xCux /BCZY = 60:40 wt%. The powder is calcined at a temperature of 700 °C, sintered at 1450 °C, and reduced by pure H2. The results of the Ni1-xCux-BCZY microstructure show an increase in the average particle size from 2.71 to 2.88 µm with increasing calcination time from 0.5 to 1.5 hours. Furthermore, the conductivity of Ni1-xCux-BCZY (x = 0.1) is lower than Ni1-xCux-BCZY (x = 0), this is associated with enhancement electron scattering, which correlatives with large metal particle obtained. The optimum conductivity of Ni1-xCux-BCZY(x=0.1) is obtained at a calcination time of 0.5 hours. Furthermore, NiCu anode can effectively increase the carbon resistance while using methane as a fuel.


2019 ◽  
Vol 34 ◽  
pp. 46-52
Author(s):  
Iulian Ştefan ◽  
Gabriel Benga ◽  
Ionel Dănuț Savu ◽  
Sorin Vasile Savu ◽  
Adrian Olei

In this paper, BaFe2O4 was prepared from BaCO3 and Fe2O3 powders through the solid state reaction method. This method starts by mixing the barium carbonate and iron oxide in order to homogenize the raw materials and takes place in a wet medium. For a better homogenization of BaCO3 and Fe2O3 powders and in order to reduce the monoferrite formation temperature, it was used the mechanical alloying process for 3 and 9 hours in a high energy ball mill. Particle size distributions of the milled powders were analyzed by a BROOKHAVEN 90PLUS device. To understand the phase formation temperature, thermogravimetry analysis was carried out. The phase identification of the calcined powder was carried out by D8 Discover Bruker X-ray diffractometer. The results showed that once with the reduction of powders particle size, in the mechanical alloying process, the temperature of the solid state reaction of barium monoferrite was also reduced.


2014 ◽  
Vol 90 ◽  
pp. 133-140
Author(s):  
Erkul Karacaoglu ◽  
Bekir Karasu ◽  
Esra Öztürk

The Akermanite type alkaline earth silicate Ca2MgSi2O7 activated by different types of rare earths was prepared by the conventional solid state reaction method under weak reductive atmosphere. The phase formation, particle size distribution, particle morphologies and photoluminescence properties of the samples have been investigated respectively. The comparative results of SEM and laser particle size analysis revealed that the relatively regular morphology, smaller particle size distribution could be achieved for the phosphors synthesized by the solid state reaction method including dry-ground after which powders were sieved below 170 meshes. The effects of rare earth oxides; Nd2O3, Pr6O11, Ce2O3 and Sm2O3 on the luminescence properties of the host material, Ca2MgSi2O7, were studied. Remarkable enhancement and novel color emitting including white in luminescence characteristics of host material were observed as a result of doping the mentioned rare-earths were doped.


2008 ◽  
Vol 55-57 ◽  
pp. 197-200 ◽  
Author(s):  
Atthakorn Thongtha ◽  
Kritsana Angsukased ◽  
Theerachai Bongkarn

The effect of calcination temperatures (1000-1400 oC) on the phase formation and microstructure of barium strontium zirconate titanate [(Ba0.25Sr0.75)(Zr0.75Ti0.25)O3 ; BSZT] powders were investigated. BSZT powders were prepared and compared by the solid state reaction method and the combustion technique. The higher calcination temperatures increased the percentage of the perovskite phase, but decreased the lattice parameter a. The same crystallographic pure perovskite phase of BSZT powders, which were prepared via the combustion technique were detected above 1300 oC ; which was lower than the calcinations temperature of mixed oxide method by 50 oC. The TGA-DTA results corresponded to XRD investigation. The microstructure of BSZT powders, which were prepared using both techniques, exhibited an almost-spherical morphology and had a porous agglomerated form. The average particle sizes of BSZT powders prepared via the combustion technique (0.13-0.30 µm) and the solid state reaction method (0.18-0.38 µm) were increased with the increase of calcinations temperatures


2021 ◽  
Vol 51 (3) ◽  
pp. 599-604
Author(s):  
Kanchan Upadhyay ◽  
Sabu Thomas ◽  
Nandakumar Kalarikkal ◽  
Raunak Kumar Tamrakar

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