Optical induction in K0.5Na0.5NbO3 ferroelectric ceramic at low calcination temperature by sol-gel route

Pure and silver added zinc oxide nanoparticles ( ZnO -NPs and ZnO : Ag -NPs) were synthesized through a modified sol–gel method. The prepared samples were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. In the XRD patterns, silver diffracted peaks were also observed for the samples synthesized at different calcination temperatures of 500°C, 700°C, 900°C except 1100°C, in addition to ZnO . TEM images indicated that the average size of ZnO : Ag -NPs increases with the amount of Ag concentration. The PL spectra of the samples revealed that the increase of Ag concentration results in the increase of the visible emission intensity, whereas by increasing the calcination temperature the intensity of visible emission of the samples decreases.

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Texture Evaluation of Sol-Gel Derived Mesoporous Bioactive Glass

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.284-287.230 ◽

2013 ◽

Vol 284-287 ◽

pp. 230-234

Author(s):

Yu Jen Chou ◽

Chi Jen Shih ◽

Shao Ju Shih

Keyword(s):

Surface Area ◽

Calcination Temperature ◽

High Surface ◽

Sol Gel ◽

High Surface Area ◽

Nitrogen Adsorption ◽

Bioactive Glasses ◽

Transmission Electron ◽

Sol Gel Process ◽

Adsorption Desorption

Recent years mesoporous bioactive glasses (MBGs) have become important biomaterials because of their high surface area and the superior bioactivity. Various studies have reported that when MBGs implanted in a human body, hydroxyl apatite layers, constituting the main inorganic components of human bones, will form on the MBG surfaces to increase the bioactivity. Therefore, MBGs have been widely applied in the fields of tissue regeneration and drug delivery. The sol-gel process has replaced the conventional glasses process for MBG synthesis because of the advantages of low contamination, chemical flexibility and lower calcination temperature. In the sol-gel process, several types of surfactants were mixed with MBG precursor solutions to generate micelle structures. Afterwards, these micelles decompose to form porous structures after calcination. Although calcination is significant for contamination, crystalline and surface area in MBG, to the best of the authors’ knowledge, only few systematic studies related to calcination were reported. This study correlated the calcination parameters and the microstructure of MBGs. Microstructure evaluation was characterized by transmission electron microscopy and nitrogen adsorption/desorption. The experimental results show that the surface area and the pore size of MBGs decreased with the increasing of the calcination temperature, and decreased dramatically at 800°C due to the formation of crystalline phases.

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INFLUENCE OF PH AND CALCINATION TEMPERATURE ON MAGNETIC PROPERTIES OF NANOSIZED ZN-FERRITE SYNTHESIZED BY SOL–GEL CITRATE METHOD

International Journal of Research in Engineering and Technology ◽

10.15623/ijret.2017.0613006 ◽

2017 ◽

Vol 06 (13) ◽

pp. 23-29

Author(s):

Samarjit Singh .

Keyword(s):

Magnetic Properties ◽

Calcination Temperature ◽

Sol Gel ◽

Citrate Method ◽

Zn Ferrite ◽

Influence Of Ph

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Calcination Effect on Structural Trasformation of Barium Titanite Ferroelectric Ceramic by Sol-Gel Method

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.a3023.109119 ◽

2019 ◽

Vol 9 (1) ◽

pp. 5893-5896

Keyword(s):

Glacial Acetic Acid ◽

Sol Gel ◽

Ferroelectric Ceramic ◽

Tetrabutyl Titanate ◽

Chemical Modifier ◽

Barium Acetate ◽

X Ray Diffraction ◽

X Ray ◽

Gel Technique ◽

Scanning Electron

High purity barium titanate BaTiO3 was successfully synthesized by using the sol-gel technique. Barium acetate Ba(CH3COO)2 and tetrabutyl titanate, Ti(C4H9O)4 was dissolved moderately in the solvent of glacial acetic acid and ethanol was added as the chemical modifier. The synthesized BaTiO3 nanoparticle was calcined at the temperature range of 700 ºC to 1100 ºC. The powders were further characterized by X-ray diffraction and scanning electron microscopy (SEM). Fined BaTiO3 powders result indicates the phase of tetragonal structures and high crystallites of BaTiO3. It was observed that the crystallinity and particle size of BaTiO3 is greatly influenced by the calcination temperature.

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Bismuth Oxide Prepared by Sol-Gel Method: Variation of Physicochemical Characteristics and Photocatalytic Activity Due to Difference in Calcination Temperature

Indonesian Journal of Chemistry ◽

10.22146/ijc.53144 ◽

2020 ◽

Vol 21 (1) ◽

pp. 108

Author(s):

Yayuk Astuti ◽

Brigita Maria Listyani ◽

Linda Suyati ◽

Adi Darmawan

Keyword(s):

Photocatalytic Activity ◽

Band Gap ◽

Calcination Temperature ◽

Bismuth Oxide ◽

Sol Gel ◽

Physicochemical Characteristics ◽

Band Gap Energy ◽

Gel Method ◽

Sol Gel Method ◽

Body Center Cubic

Research on synthesis of bismuth oxide (Bi2O3) using sol-gel method with varying calcination temperatures at 500, 600, and 700 °C has been done. This study aims to determine the effect of calcination temperature on the characteristics of the obtained products which encompasses crystal structure, surface morphology, band-gap energy, and photocatalytic activity for the decolorization of methyl orange dyes through its kinetic study. Bismuth oxide prepared by sol-gel method was undertaken by dissolving Bi(NO3)3·5H2O and citric acid in HNO3. The mixture was stirred then heated at 100 °C. The gel formed was dried in the oven and then calcined at 500, 600, and 700 °C for 5 h. The obtained products were a pale yellow powder, indicating the formation of bismuth oxide. This is confirmed by the existence of Bi–O and Bi–O–Bi functional groups through FTIR analysis. All three products possess the same mixed crystal structures of α-Bi2O3 (monoclinic) and γ-Bi2O3 (body center cubic), but their morphologies and band gap values are different. The higher the calcination temperature, the larger the particle size and the smaller the band gap value. The accumulative differences in characteristics appoint SG700 to have the highest photocatalytic activity compared to SG600 and SG500 as indicated by its percent degradation value and decolorization rate constant.

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Effect of the calcination temperature on the photocatalytic efficiency of acidic sol–gel synthesized TiO2nanoparticles in the degradation of alprazolam

Photochemical & Photobiological Sciences ◽

10.1039/c6pp00447d ◽

2017 ◽

Vol 16 (6) ◽

pp. 935-945 ◽

Cited By ~ 7

Author(s):

Andreia Romeiro ◽

Diana Freitas ◽

M. Emília Azenha ◽

Moisés Canle ◽

Hugh D. Burrows

Keyword(s):

Aqueous Solution ◽

Titanium Dioxide ◽

Calcination Temperature ◽

Sol Gel ◽

Psychoactive Drug ◽

Photocatalytic Efficiency ◽

Titanium Dioxide Photocatalysis

The benzodiazepine psychoactive drug alprazolam is efficiently photodegraded and mineralized in aqueous solution using titanium dioxide photocatalysis.

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The Influence of Calcination Temperature on Photocatalytic Activity of TiO2-Acetylacetone Charge Transfer Complex towards Degradation of NOx under Visible Light

Catalysts ◽

10.3390/catal10121463 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1463

Author(s):

Lucas A. Almeida ◽

Margarita Habran ◽

Rafael dos Santos Carvalho ◽

Marcelo E. H. Maia da Costa ◽

Marco Cremona ◽

...

Keyword(s):

Photocatalytic Activity ◽

Charge Transfer ◽

Visible Light ◽

Calcination Temperature ◽

Charge Transfer Complex ◽

Light Exposure ◽

Sol Gel ◽

Solar Spectrum ◽

Photocatalytic Efficiency ◽

Nanocrystalline Tio2

The improvement of photocatalytic activity of TiO2-based nanomaterials is widely investigated due to the tentative of their industrialization as environmental photocatalysts and their inherently low solar spectrum sensitivity and rapid recombination of charge carriers. Coupling of oxygen-based bidentate diketone to nanocrystalline TiO2 represents a potential alternative for improving the holdbacks. Formation of TiO2-acetylacetone charge transfer complex (CTC) by sol-gel route results in a hybrid semiconductor material with photodegradation activity against toxic NOx gas. In this research, the influence of the chelating agent acetylacetone (ACAC) content on the CTC photocatalytic efficiency under visible light was evaluated. A high content of ACAC in the CTC is not a decisive factor for efficiency of photocatalytic reactions. In fact, the highest efficiency for NOx degradation (close to 100%, during 1 h of visible light exposure) was reported for the material calcined in air at 300 °C with the content of strongly bonded acetylacetone not higher than 3 wt.%. Higher calcination temperature (400 °C) left TiO2 almost completely depleted in ACAC, while at the highest applied temperature (550 °C) a portion of anatase was transformed into rutile and the sample is free of ACAC. The analyses pointed out that superoxide anion radical (O2−) plays an active role in photo-oxidation of NOx. Our findings indicate that this CTC has both high visible light spectral sensitivity and photocatalytic efficiency.

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