Synthesis of BaTiO3 and Ba(ZrxTi1-X)O3 by using the soft combustion method

Author(s):  
Atiqah Ahmad ◽  
Khairunisak Abdul Razak
2016 ◽  
Vol 19 ◽  
pp. 816-821 ◽  
Author(s):  
Khairunisak Abdul Razak ◽  
Wai Chen Song ◽  
Chai Yan Ng

2012 ◽  
Vol 620 ◽  
pp. 156-160
Author(s):  
Khairunisak Abdul Razak ◽  
Mohamad Afifi Anuar ◽  
Chai Yan Ng

In this work, 20 % Pr doped bismuth sodium titanate (PBNT) powders were synthesized using the soft combustion technique. Three combustion agents; polyethylene glycol 200, citric acid and glycine with 0.2, 2.0 and 5.0 mol were used to aid combustion process. A single phase PBNT was obtained with the addition of 5 mol % citric acid. For most compounds, secondary phases presence such as Bi4Ti3O12and Bi2Ti2O7. In general, crystallite size increased with increasing sintering temperature that was due to diffusion of ions at high temperature. Dielectric properties increased with increasing densities. The optimum properties were obtained for PBNT synthesized using 5 mol % citric acid sintered at 1100°C for 3 hours which gave the highest dielectric constant (1153.20), acceptable loss tangent (0.1074) and high relative density (95.03).


2019 ◽  
Author(s):  
Liqun Cao ◽  
Jinzhe Zeng ◽  
Mingyuan Xu ◽  
Chih-Hao Chin ◽  
Tong Zhu ◽  
...  

Combustion is a kind of important reaction that affects people's daily lives and the development of aerospace. Exploring the reaction mechanism contributes to the understanding of combustion and the more efficient use of fuels. Ab initio quantum mechanical (QM) calculation is precise but limited by its computational time for large-scale systems. In order to carry out reactive molecular dynamics (MD) simulation for combustion accurately and quickly, we develop the MFCC-combustion method in this study, which calculates the interaction between atoms using QM method at the level of MN15/6-31G(d). Each molecule in systems is treated as a fragment, and when the distance between any two atoms in different molecules is greater than 3.5 Å, a new fragment involved two molecules is produced in order to consider the two-body interaction. The deviations of MFCC-combustion from full system calculations are within a few kcal/mol, and the result clearly shows that the calculated energies of the different systems using MFCC-combustion are close to converging after the distance thresholds are larger than 3.5 Å for the two-body QM interactions. The methane combustion was studied with the MFCC-combustion method to explore the combustion mechanism of the methane-oxygen system.


2020 ◽  
Vol 61 (6) ◽  
pp. 725-731
Author(s):  
M. I. Alymov ◽  
V. I. Uvarov ◽  
R. D. Kapustin ◽  
A. O. Kirillov ◽  
V. E. Loryan

2020 ◽  
Vol 5 (3) ◽  
pp. 236-251
Author(s):  
Eshwara I. Naik ◽  
Halehatty S.B. Naik ◽  
Ranganaik Viswanath

Background: Various interesting consequences are reported on structural, optical, and photoluminescence properties of Zn1-xSmxO (x=0, 0.01, 0.03 and 0.05) nanoparticles synthesized by sol-gel auto-combustion route. Objective: This study aimed to examine the effects of Sm3+-doping on structural and photoluminescence properties of ZnO nanoparticles. Methods: Zn1-xSmxO (x=0, 0.01, 0.03 and 0.05) nanoparticles were synthesized by sol-gel auto combustion method. Results: XRD patterns confirmed the Sm3+ ion substitution through the undisturbed wurtzite structure of ZnO. The crystallite size was decreased from 24.33 to 18.46 nm with Sm3+ doping. The hexagonal and spherical morphology of nanoparticles was confirmed by TEM analysis. UV-visible studies showed that Sm3+ ion doping improved the visible light absorption capacity of Sm3+ iondoped ZnO nanoparticles. PL spectra of Sm3+ ion-doped ZnO nanoparticles showed an orange-red emission peak corresponding to 4G5/2→6HJ (J=7/2, 9/2 and 11/2) transition of Sm3+ ion. Sm3+ ion-induced PL was proposed with a substantial increase in PL intensity with a blue shift in peak upon Sm3+ content increase. Conclusion: Absorption peaks associated with doped ZnO nanoparticles were moved to a longer wavelength side compared to ZnO, with bandgap declines when Sm3+ ions concentration was increased. PL studies concluded that ZnO emission properties could be tuned in the red region along with the existence of blue peaks upon Sm3+ ion doping, which also results in enhancing the PL intensity. These latest properties related to Sm3+ ion-doped nanoparticles prepared by a cost-efficient process appear to be interesting in the field of optoelectronic applications, which makes them a prominent candidate in the form of red light-emitting diodes.


2020 ◽  
Vol 1 (1) ◽  
pp. 30-36
Author(s):  
Shubha Jayachamarajapura Pranesh ◽  
Diwya Lanka

Background: Textile industries discharge harmful synthetic dyes to nearby water sources. These colour effluents should be treated before discharge to reduce the toxicity caused by synthetic colours. Objective: To synthesize visible light active superstructures to reduce water pollution caused by textile industries. Methods: We have successfully synthesized ZnO/Dy/NiO hybrid nanocomposites using waste curd as fuel by a simple combustion method. The obtained material was able to reduce recombination and enhanced the photocatalytic degradation of organic pollutants. The as-synthesized material was characterized by XRD, absorption spectroscopy, FESEM, EDAX, etc. The obtained hybrid nanostructure was used as a photocatalyst for the degradation of methylene blue under sunlight, UV light as well as in dark. Comparative experiments were carried out with a variation of catalytic load, pH, dye concentrations, etc. for a better understanding of the performance of the catalyst at various conditions. Results and Conclusion: The ternary compound shows wide range of absorption by expanding absorption band both in UV and visible regions. ZnO/Dy/NiO hybrid nanocomposites performed well and showed uniqueness in the activity uder visible light.


2021 ◽  
Vol 267 ◽  
pp. 115054
Author(s):  
Yatish R. Parauha ◽  
Vaibhavi Sahu ◽  
S.J. Dhoble
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