scholarly journals Synthesis of Cubic Phase-Co Microspheres by Mechanical Solid-State Reaction-Thermal Decomposition and Research on Its Growth Kinetics

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Ying Deng ◽  
Yanhua Zhang ◽  
Lingling Peng ◽  
Xiaolong Jing ◽  
Hui Chen
Keyword(s):  
Thermal Decomposition ◽  
Solid State ◽  
Grain Growth ◽  
Solid State Reaction ◽  
Room Temperature ◽  
Energy Content ◽  
Industrial Applications ◽  
Cubic Phase ◽  
Oxalate Precursor ◽  
Cobalt Oxalate

Cubic phase cobalt (Co), which can be used as a key component for composite materials given its excellent ductility and internal structure, is not easy to obtain at room temperature. In this study, oxalic acid and cobalt nitrate are used as raw materials to synthesize the cobalt oxalate precursor, which has a stable structure with a five-membered chelate ring. Cobalt oxalate microspheres, having a high internal energy content, were prepared by using mechanical solid-state reaction in the presence of a surfactant, which can produce spherical micelles. The thermal decomposition of the precursor was carried out by maintaining it in a nitrogen atmosphere at 450°C for 3 h. At the end of the procedure, 100 nm cubic phase-Co microspheres, stable at room temperature, were obtained. Isothermal and nonisothermal kinetic mechanisms of cobalt grain growth were investigated. The cubic-Co grain growth activation energy, Q, was calculated in this study to be 71.47 kJ/mol. The required reaction temperature was low, making the production process simple and suitable for industrial applications.

Phase relations in the Ba–Sr–Co–Fe–O system at 1273 K in air

2009 ◽  
Vol 42 (2) ◽  
pp. 153-160 ◽  
Author(s):  
Zhèn Yáng ◽  
Ashley S. Harvey ◽  
Anna Infortuna ◽  
Ludwig J. Gauckler
Keyword(s):  
High Temperature ◽  
Solid State ◽  
Solid State Reaction ◽  
Room Temperature ◽  
Solid State Reaction Method ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray

Selected compositions of the Ba–Sr–Co–Fe–O system were synthesized from powders by the solid-state reaction method. Samples were equilibrated at 1273 K for 36 000 s in air. The resulting powders were characterized by X-ray diffraction (XRD) at room temperature and by high-temperaturein situXRD. The phases present in the BaxSr1−xCoyFe1−yO3−δsystem are outlined for 1273 K in air. For most of the quaternary compositions, the cubic perovskite is formed, except for the compositions withx= 1 (excludingy= 0.4),y= 1 andx,y= 0.8, where the phases mainly show hexagonal distortions, andx, y= 0, for which a predominant cubic phase is mixed with other phases.

Decrease in Resistance of Ceria Oxygen Sensor Induced by 10 mol% Hf and Zr Doping

2005 ◽  
Vol 888 ◽  
Author(s):  
Noriya Izu ◽  
Woosuck Shin ◽  
Ichiro Matsubara ◽  
Norimitsu Murayama
Keyword(s):  
Solid State ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Solid State Reaction ◽  
Pressure Range ◽  
Oxygen Sensor ◽  
Cubic Phase ◽  
Doped Ceria ◽  
Oxygen Gas ◽  
Resistive Type

ABSTRACTResistive type sensors using 10 mol% Hf-doped ceria and 10 mol% Zr-doped ceria, which had a single cubic phase obtained by solid state reaction, were fabricated and their sensing properties were investigated. The resistance and resistivity of the 10 mol% Hf-doped ceria or 10 mol% Zr-doped ceria were smaller than those of non-doped ceria. In the case of the same temperature of solid state reaction, the resistance and resistivity of the 10 mol% Hf-doped ceria were much smaller than those of the 10 mol% Zr-doped ceria. Furthermore, in the case of the same dopant, the resistance and resistivity of the sensor prepared from the solid state reaction at 1773 K were much smaller than those at 1673 K. The sensor using the 10 mol% Hf-doped ceria could be used as an oxygen gas sensor in wide oxygen partial pressure range and could be applicable to a λ sensor and a universal A/F sensor.

Preparation of High-Purity Ultrafine α-Al2O3 by Solid-State Reaction at Room Temperature

2008 ◽  
Vol 368-372 ◽  
pp. 683-685
Author(s):  
Cheng Wei Hao ◽  
Bo Lin Wu ◽  
Ji Yan Li
Keyword(s):  
Solid State ◽  
High Purity ◽  
Solid State Reaction ◽  
Room Temperature ◽  
Raw Materials ◽  
Phase Particle ◽  
Phase Transformation Temperature ◽  
Particle Size And Morphology ◽  
Size And Morphology ◽  
Α Al2o3

Ammonium aluminium carbonate hydroxide (AACH), with a small quantity of γ-AlOOH, was synthesized through solid-state reaction at room temperature using AlCl3·6H2O and NH4HCO3 as raw materials and polyethylene glycol (PEG-10000) as the dispersant. After calcined at 1100°C for 1.5h, α-Al2O3 powders with primary particle sizes of 20~30nm were obtained. The crystal phase, particle size and morphology of the high-purity ultrafine α-Al2O3 were characterized. The results showed that a small quantity of γ-AlOOH in the AACH decomposed and formed crystal seeds. The presence of crystal seeds reduced the nucleation activation energy and therefore reduced the phase transformation temperature.

Co/Mn-Coated LiNiO2 Cathode Materials by Solid-State Reaction at Room Temperature

2008 ◽  
Vol 37 (11) ◽  
pp. 1881-1886 ◽  
Author(s):  
Guorong Hu ◽  
Xinrong Deng ◽  
Zhongdong Peng ◽  
Ke Du ◽  
Yanbin Cao ◽  
...  
Keyword(s):  
Solid State ◽  
Cathode Materials ◽  
Solid State Reaction ◽  
Room Temperature

Thermal study of NiC2O4·2H2O obtained by a solid state reaction at room temperature and normal pressure

1987 ◽  
Vol 118 ◽  
pp. 123-134 ◽  
Author(s):  
M.E. García-Clavel ◽  
M.J. Martinez-Lope ◽  
M.T. Casais-Alvarez
Keyword(s):  
Solid State ◽  
Solid State Reaction ◽  
Room Temperature ◽  
Normal Pressure ◽  
Thermal Study

Facile preparation of polyoxometalate nanoparticles via a solid-state chemical reaction for aerobic oxidative desulfurization catalysis

2021 ◽  
Author(s):  
Hang Yu ◽  
Wenwen Bu ◽  
Zijia Wang ◽  
Zhuoyue Zhao ◽  
Mehwish Jadoon ◽  
...  
Keyword(s):  
Solid State ◽  
Silver Nitrate ◽  
Chemical Reaction ◽  
Solid State Reaction ◽  
Room Temperature ◽  
Oxidative Desulfurization ◽  
Solid State Reaction Method ◽  
Reaction Method ◽  
State Chemical ◽  
Facile Preparation

Polyoxometalate nanoparticles were synthesized via a concise solid-state reaction method by directly grinding silver nitrate and the polyoxometalate (NH4)5H6PMo4V8O40 at room temperature without the assistance of a surfactant.

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