scholarly journals Reaction Mechanism and Kinetic Analysis of the Solid-State Reaction to Synthesize Single-Phase Li2Co2O4 Spinel

2020 ◽  
Vol 124 (15) ◽  
pp. 8170-8177
Author(s):  
Kingo Ariyoshi ◽  
Kazuki Yuzawa ◽  
Yusuke Yamada
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Juan P. Yasnó ◽  
Susana Conconi ◽  
Arnaldo Visintin ◽  
Gustavo Suárez

AbstractNon-isothermal reaction mechanism and kinetic analysis for the synthesis of monoclinic lithium zirconate (m-Li2ZrO3) were investigated by processing of TG-DTA, along with XRD, DLS, and HRTEM. For this purpose, the solid-state reaction of Li2CO3 with ZrO2 was carried out by TG-DTA at different heating rates (10, 20, and 30 °C/min) from room temperature to 1100 °C. The thermal data was used to calculate the kinetic parameters by two types of isoconversional methods: Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS). The reaction mechanism was determined by the model-fitting method, applying the Coats-Redfern (CR) approximation to the different solid-state reaction models. The results confirmed the formation of pure m-Li2ZrO3, consists of semispherical particles of about 490 nm, using a very short reaction time. The average activation energy obtained by FWO and KAS methods were 274.73 and 272.50 kJ/mol, respectively. It was found that the formation of m-Li2ZrO3 from Li2CO3 with ZrO2 is governed by the three-dimensional diffusion mechanism. Based on these results, a microscopic reaction model of the formation of m-Li2ZrO3 was proposed.


2010 ◽  
Vol 49 (8) ◽  
pp. 3597-3602 ◽  
Author(s):  
Liping Ma ◽  
Ping Ning ◽  
Shaocong Zheng ◽  
Xuekui Niu ◽  
Wei Zhang ◽  
...  

2008 ◽  
Vol 368-372 ◽  
pp. 588-590 ◽  
Author(s):  
Ming Hao Fang ◽  
Jun Tong Huang ◽  
Zhao Hui Huang ◽  
Yan Gai Liu ◽  
Bin Jiang ◽  
...  

Single phase YIG powders were synthesized successfully using Fe2O3 and Y2O3 as starting materials by solid state reaction, and YIG ceramics were prepared by pressureless sintering. The influence of synthesizing temperature and Fe2O3 content on the final production were studied The effect of Fe2O3 content on volume density and microstructure of the sintered YIG was also investigated. The results showed that single phase YIG powders were synthesized by solid state reaction at 1400°C for 3h. When Fe2O3 content was excessive 3 wt%, YIG ceramics with a density of 5.294g·cm-3 was fabricated by sintering at 1480°C for 2.5h.


2014 ◽  
Vol 2 (38) ◽  
pp. 15829-15835 ◽  
Author(s):  
Kriti Tyagi ◽  
Bhasker Gahtori ◽  
Sivaiah Bathula ◽  
A. K. Srivastava ◽  
A. K. Shukla ◽  
...  

Intrinsically ultra-low thermal conductivity and electrical transport in single-phase Cu2SbSe3 synthesized employing a solid state reaction and spark plasma sintering.


2012 ◽  
Vol 512-515 ◽  
pp. 158-161 ◽  
Author(s):  
Ling Dai ◽  
Qiang Xu ◽  
Shi Zhen Zhu ◽  
Ling Liu

As a new candidate material for the ceramic layer in thermal barrier coatings (TBCs) system, La3NbO7 was synthesized with La2O3 powder and Nb2O5 powder by solid state reaction. The stating powders with a mole ratio of La to Nb of 3:1 were mixed and then the mixture was calcined under the different temperatures(800°C, 1000°C, 1200°C) and dwell times(2h, 6h, 10h). The phase structure of the powder was observed by X–ray diffraction(XRD), and the microstructure of the sample was observed by scanning electron microscope(SEM). The effect of calcination temperature and dwell Time on the phase formation were examined. The results indicate that the La3NbO7 powder with single phase can be synthesized successfully at 1200°C for 10h in air, and the La3NbOsub>7 powders synthesized have an ultra-fine particle size of 0.5˜1µm with a granular particle shape. With the temperature increasing, LaNbO4/sub> was synthesized firstly and then La3NbO7 was synthesized with a mole ratio of La2O3 to LaNbO4 of 1:1.


2003 ◽  
Vol 18 (1) ◽  
pp. 4-7 ◽  
Author(s):  
Y. C. Sohn ◽  
Jin Yu ◽  
S. K. Kang ◽  
W. K. Choi ◽  
D. Y. Shih

The reaction mechanism between electroless Ni–P and Sn was investigated to understand the effects of Sn on solder reaction-assisted crystallization at low temperatures as well as self-crystallization of Ni–P at high temperatures. Ni3Sn4 starts to form in a solid-state reaction well before Sn melts. Heat of reaction for Ni3Sn4 was measured during the Ni–P and Sn reaction (241.2 J/g). It was found that the solder reaction not only promotes crystallization at low temperatures by forming Ni3P in the P-rich layer but also facilitates self-crystallization of Ni–P by reducing the transformation temperature and heat of crystallization. The presence of Sn reduces the self-crystallization temperature of Ni–P by about 10 °C. The heat of crystallization also decreases with an increased Sn thickness.


2013 ◽  
Vol 683 ◽  
pp. 199-202 ◽  
Author(s):  
Jia Yue Sun ◽  
Dian Peng Cui ◽  
Bing Xue ◽  
Guang Chao Sun ◽  
Hai Yan Du

A series of single-phase Sr5(PO4)3F: Eu2+, Tb3+, Na+ phosphors have been synthesized by high temperature solid-state reaction. The photoluminescence excitation and emission spectra, concentration effect and energy transfer from Eu2+ to Tb3+ are investigated in detail. The work shows that there is an effective energy transfer from Eu2+ to Tb3+, where Eu2+ reveals an intense excitation band from 280 nm to 400 nm, matching well with the emission of n-UV chips, and Tb3+ emits an intense green emitting light.


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