Microwave assisted synthesis of La-1 (-) xCaxMnO3 (x=0, 0.2 and 0.4): Structural and capacitance properties

2017-12-01
Tabari, Taymaz
Singh, Dheerendra
Calisan, Atalay
Ebadi, Mehdi
Tavakkoli, Haman
Caglar, Basar
Show full item record
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
233
views
0
downloads
The effect of calcium incorporation on the physicochemical and electrochemical properties of the LaMnO3 (LM) perovskites was studied via several techniques. Moreover, a new microwave assisted method was used to synthesize La(1-x)Ca(,)M(x)nO(3)(LCM) perovskites with various calcium content (x = 0.2 and 0.4). Then, the physicochemical properties of the materials such as crystal structure, particle size, surface area, reducibility and band gap energy were investigated by X-ray Diffraction (XRD), High resolution Scanning and Transmission Electron Microscope (HR-SEM and HR-TEM), BET analysis, Temperature-programmed Reduction (TPR) and UV-visible Diffuse Reflectance Spectroscopy (UV-VIS DRS). The increase in partial concentration of calcium resulted in a high specific surface area, larger particle size and an enhanced reducibility along with an increase in the band gap energy. In addition, cyclic voltammetry was applied to LM and LCM perovskites to determine the effect of calcium incorporation on the capacitance of the electrochemical cell. It showed that the capacitance decreases with the amount of Ca2+ incorporated into the LM structure. This effect is linked to the formation of Mn4+, which hinders the electron transfer in the structure. The decline in the charge transfer is revealed by the specific capacitance. Finally, our findings showed that the microwave assisted method provides a green, efficient and time-saving route for perovskite synthesis and the calcium incorporation induces a negative effect on the capacitance properties of the LM perovskites.
Perovskite-type oxide, Microwave-assisted synthesis, Oxygen vacancy, Capacitance property
https://hdl.handle.net/11511/68265
CERAMICS INTERNATIONAL
Department of Chemical Engineering, Article

Suggestions

Biological and green synthesis of silver nanoparticles
Forough, Mehrdad; Khalil, Farhadi (2010-12-01)
In this work, the synthesis of stable silver nanoparticles by the bioreduction method was investigated. Aqueous extracts of the manna of hedysarum plant and the soap-root (Acanthe phylum bracteatum) plant were used as reducing and stabilizing agents, respectively. UV-Vis absorption spectroscopy was used to monitor the quantitative formation of silver nanoparticles. The characteristics of the obtained silver nanoparticles were studied using X-ray diffraction analysis (XRD), energy-dispersive spectroscopy (ED...
Performance evaluation of Cappadocian tuffs treated with alcohol dispersion of calcium hydroxide nano-particles
Çalışkan, Berkay Barış; Tavukçuoğlu, Ayşe; Saltık, Emine Nevin; Department of Building Science in Architecture (2022-12-08)
In this study, the effect of treatment with alcohol dispersion of calcium hydroxide Ca(OH)2 nanoparticles on controlling excessive water absorption and capillary water suction properties of Cappadocian tuffs was investigated extensively. For this purpose, two tuff types, Göreme Rock (CYT) and Cappadocian Rose (CPT), obtained from a quarry near Avanos-Nevşehir, were examined. Laboratory tests were conducted concerning their basic physical, hygric, mechanical, microstructural, and mineralogical properties bef...
Electrochemical behaviour and electrochemical polymerization of fluoro-substituted anilines
Cihaner, A; Önal, Ahmet Muhtar (2002-08-01)
The electrochemical behaviour of three fluoro-substituted aniline monomers, 2-fluoroaniline (2FAN), 3-fluoroaniline (3FAN) and 4-fluoroaniline (4FAN), was investigated in aqueous acidic and organic media by means of cyclic voltammetry (CV) studies. Constant potential electrolysis (CPE) of the monomers in acetonitrile-water mixture (1: 1 by volume) using NaClO4 as supporting electrolyte yielded soluble polymers. The mechanism of electrochemical polymerization was investigated using in situ electron spin reso...
Syntheses of new monomeric and polymeric units and electrochemical behaviors for the use in electrochromic applications
Zaifoğlu, Nazlı Buket; Toppare, Levent Kamil; Çırpan, Ali; Department of Chemistry (2013)
4'-(Tert-butyl)-4,7-di(thiophen-2-yl)spiro[benzo[d]imidazole-2,1'-cyclohexane], 4,7-di([2,2'-bithiophen]-5-yl)-4'-(tert-butyl)spiro[benzo[d]imidazole-2,1'-cyclohexane], 4'-(tert-butyl)-4,7-bis(thieno[3,2-b]thiophen-2-yl)spiro[benzo[d]imidazole-2,1'- cyclohexane] were synthesized, electrochemically polymerized and electrochromic properties of resultant polymers were investigated. The monomers were characterized by nuclear magnetic resonance spectroscopy (1H-NMR, 13C-NMR). Cyclic voltammetry (CV) and ultravio...
Polyethylene oxide-hydroxyapatite composite and microporous polyethylene oxide-polymethacrylic acid polymer complex preparation and characterization
Banat, Raid M I; Tinçer, Teoman; Department of Chemistry (2002)
The first part of this study covers the crosslinking of polyethylene oxide (PEO) and its composite with calcium hydroxyapatite (HA) and their mechanical, swelling and morphological properties. Sheets of neat PEO (two different molecular weights) and composites of PEO-HA were prepared by compression molding. The composites and PEO thick sheets were crosslinked with exposure of UV- irradiation in presence of acetophenone (AP) for different periods of time. This simple method of crosslinking, UV-irradiation in...
Citation Formats
T. Tabari, D. Singh, A. Calisan, M. Ebadi, H. Tavakkoli, and B. Caglar, “Microwave assisted synthesis of La-1 (-) xCaxMnO3 (x=0, 0.2 and 0.4): Structural and capacitance properties,” CERAMICS INTERNATIONAL, pp. 15970–15977, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/68265.
METU IIS - Integrated Information Service open@metu.edu.tr