scholarly journals The Synthesis and Characterization of Sol-Gel-Derived SrTiO3-BiMnO3 Solid Solutions

Crystals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1125
Author(s):  
Dovydas Karoblis ◽  
Ramunas Diliautas ◽  
Eva Raudonyte-Svirbutaviciene ◽  
Kestutis Mazeika ◽  
Dalis Baltrunas ◽  
...  

In this study, the aqueous sol-gel method was employed for the synthesis of (1−x)SrTiO3-xBiMnO3 solid solutions. Powder X-ray diffraction analysis confirmed the formation of single-phase perovskites with a cubic structure up to x = 0.3. A further increase of the BiMnO3 content led to the formation of a negligible amount of neighboring Mn3O4 impurity, along with the major perovskite phase. Infrared (FT-IR) analysis of the synthesized specimens showed gradual spectral change associated with the superposition effect of Mn-O and Ti-O bond lengths. By introducing BiMnO3 into the SrTiO3 crystal structure, the size of the grains increased drastically, which was confirmed by means of scanning electron microscopy. Magnetization studies revealed that all solid solutions containing the BiMnO3 component can be characterized as paramagnetic materials. It was observed that magnetization values clearly correlate with the chemical composition of powders, and the gradual increase of the BiMnO3 content resulted in noticeably higher magnetization values.

2017 ◽  
Vol 748 ◽  
pp. 413-417
Author(s):  
Chun Yu Long ◽  
Fang Fang Peng ◽  
Min Min Jin ◽  
Pei Song Tang ◽  
Hai Feng Chen

Using Pr (NO3)3, butyl titanate, ethylene glycol and citric acid as main raw materials, praseodymium titanate (Pr2Ti2O7) was prepared by the sol-gel process. The samples were characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), thermal gravity-differential thermal analysis (TG-DTA), diffuse-reflection spectra (DRS) and Fourier transform infrared (FT-IR). The effect of different calcination temperature and illumination time on the photocatalytic properties of Pr2Ti2O7 was investigated. It was found that the single phase Pr2Ti2O7 could be obtained through sol-gel process and calcination at 1000 °C. The Pr2Ti2O7 samples calcination at 1000 °C were uniform , and the resulting product had a particle size of 200 nm and an optical band gap of 3.26 eV. Under ultraviolet light, the degradation of methyl orange arrived to 80.11% after 180 min of photocatalytic reaction. The Pr2Ti2O7 samples showed good photocatalytic activity for decomposition of methyl orange.


1996 ◽  
Vol 459 ◽  
Author(s):  
E. Ching-Prado ◽  
W. Pérez ◽  
A. Reynés-Figueroa ◽  
R. S. Katiyar ◽  
D. Ravichandran ◽  
...  

ABSTRACTThin films of SrBi2Nb2O9 (SBN) with thicknesses of 0.1, 0.2, and 0.4 μ were grown by Sol-gel technique on silicon, and annealed at 650°C. The SBN films were investigated by Raman scatering for the first time. Raman spectra in some of the samples present bands around 60, 167, 196, 222, 302, 451, 560, 771, 837, and 863 cm−1, which correspond to the SBN formation. The study indicates that the films are inhomogeneous, and only in samples with thicknesses 0.4 μ the SBN material was found in some places. The prominent Raman band around 870 cm−1, which is the A1g mode of the orthorhombic symmetry, is assigned to the symmetric stretching of the NbO6 octahedrals. The frequency of this band is found to shift in different places in the same sample, as well as from sample to sample. The frequency shifts and the width of the Raman bands are discussed in term of ions in non-equilibrium positions. FT-IR spectra reveal a sharp peak at 1260 cm−1, and two broad bands around 995 and 772 cm−1. The bandwidths of the latter two bands are believed to be associated with the presence of a high degree of defects in the films. The experimental results of the SBN films are compared with those obtained in SBT (T=Ta) films. X-ray diffraction and SEM techniques are also used for the structural characterization.


2018 ◽  
Vol 21 (1) ◽  
pp. 051-056
Author(s):  
A. Nichelson ◽  
S. Thanikaikarasan ◽  
K. Karuppasamy ◽  
S. Karthickprabhu ◽  
T. Mahalingam ◽  
...  

A new type of lithium enriched cathode material Li (Li0.05Ni0.6Fe0.1Mn0.25)O2 was synthesized by sol-gel method with citric acid as a chelating agent. The structural and morphological studies were systematically investigated through X-ray diffraction, SEM with EDS, FT-IR and Raman analyses. The crystallite size of the Li (Li0.05Ni0.6Fe0.1Mn0.25)O2 cathode material was found to be 45 nm thereby leads to the feasible movement of lithium ion all through the material. FT-IR spectroscopy was used to confirm the metal-oxygen interaction in the prepared cathode material. The electrical properties of the Li (Li0.05Ni0.6Fe0.1Mn0.25)O2 cathode material were studied by impedance and dielectric spectral analyzes. Li (Li0.05Ni0.6Fe0.1Mn0.25)O2 showed a maximum ionic conductivity of 10-6 S/cm at ambient temperature.


2011 ◽  
Vol 10 (03) ◽  
pp. 441-445 ◽  
Author(s):  
M. KARL CHINNU ◽  
L. SARAVANAN ◽  
R. JAYAVEL ◽  
C. M. RAGHAVAN ◽  
K. VIJAI ANAND ◽  
...  

Cadmium sulfide nanoparticles have been synthesized by hydrothermal method using cadmium acetate, thiosemicarbazide, and sodium hydroxide as precursors with hexamethylene tetramine as the surfactant. From the X-ray diffraction analysis, it is observed that synthesized CdS nanoparticles show cubic phase. The presence of HMTA in CdS was confirmed by FT-IR analysis. The bandgap value of CdS nanostructure has been estimated by DRS–UV-Visible spectral analysis. The formation of flower-like nanoclusters was observed using scanning electron microscopy (SEM). The application of CdS nanoparticles in photocatalytic degradation was also studied.


2011 ◽  
Vol 233-235 ◽  
pp. 1188-1191
Author(s):  
Hong Cai ◽  
Yan Chen ◽  
Yun Ying Wu

Nano-TiO2 particles were prepared by sol-gel method, of which the surfaces were coated by SiO2. The coating was achieved by the hydrolysis of sodium silicate (Na2SiO3) in ammonium chloride (NH4Cl). The surface bonding, phase constitution and chemical components of the samples were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction(XRD) and X-ray photoelectron spectroscopy (XPS). The mechanism of the SiO2 coating process onto TiO2 surface was analyzed. Results show that SiO2 particles were immobilized on the TiO2 surface via Ti—O—Si bondings, which formed at the interface. The SiO2 layer on TiO2 surface was amorphous, the photocatalytic performance was decreased of the TiO2 while its stability was enhanced after surface modification.


2008 ◽  
Vol 396-398 ◽  
pp. 481-484
Author(s):  
Rodrigo Jiménez-Gallegos ◽  
L. Téllez-Jurado ◽  
Luis M. Rodríguez-Lorenzo ◽  
Julio San Román

This paper focuses on the preparation of siloxane-polyurethane hybrid materials using a sol-gel method. The global aim of the project is to tailor mechanical properties, degradability rate, bioactivity and biocompatibility to design scaffolds for musculoskeletal applications. A series of seven hybrid materials were synthesized with varying the proportion of polydimethylsiloxane (PDMS), and Polyurethane (PU). The organic part ratios (by weight) employed were (% PDMS:% PU) 30:0, 35:5, 20:10, 15:15, 10:20, 5:25, and 0:30. The organic part was reacted with constant 70 % TEOS to obtain the hybrid materials. A sol-gel process was selected for the synthesis of the hybrids. The characterization of materials was carried out by the fourier-infrared spectroscopy (FT-IR), x-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electronic microscopy (SEM) and proton nuclear magnetic resonance (1H-NMR) techniques in order to analyze the structure, microstructure and chemical composition of the hybrid materials. Gelification time depends on the proportion of PU used. When no PU is employed, the gel time is 8 hours but it rises up to 18 days for 30 % of polyurethane. Materials range from opaque to translucent but with a greater fragility for greater amounts of polyurethane. No differences in the bonding of materials could be appreciated.


2010 ◽  
Vol 658 ◽  
pp. 49-52 ◽  
Author(s):  
Wen Kun Zhu ◽  
Xue Gang Luo ◽  
An Kai Luo ◽  
Xuan Liang

Calcium carbonate with various structures and morphologies were prepared under double injection of the CaCl2 and Na2CO3 solutions with molar ratio of 1:1 at 30 °C, taking lignin as the induction agents. They were characterized by scanning electron microscopy, infrared spectroscopy thermal analysis and X-ray diffraction. The synthesis mechanism was also discussed. The results showed that calcium carbonate of different shape were obtained with the concentration of lignin at 10g/L, 20g/L and 30g/L, respectively, under 30°C while CaCl2 and Na2CO3 were kept at the same concentration of 0.5mol/L. The size of the particles was in a range between 3 and 5μm and the particles were calcites. Compared with the normal calcium carbonate, the compound has advanced thermal decomposition behavior. Fourier transform infrared spectroscopy (FT-IR) analysis revealed the presence of lignin and calcite. The electrostatic interaction of Ca2+ with lignin and the complementary of stereo-structure play important roles in the formation of Dumbbell Shaped Calcium Carbonate.


2017 ◽  
Vol 28 (1) ◽  
pp. 76
Author(s):  
Fadhela M. Hussein

sol–gel technique conducted to synthesize nano titanium dioxide with anthraquenone (AQ) relatively in acidic pH. Nanoparticles were characterized using techniques like, Scanning Electrion Microscope (SEM), Atomic Force Microscope (AFM), UV-Visible Spectrioscopy, X-ray diffraction (XRD), Fourier transform infrared (FT-IR), SEM picture display that the TiO2/AQ is spherical in style, the band gap of TiO2/AQ nanoparticle is (3.05eV), BET and BJH analysis provides Pore volume and specific Surface area and the kinetic studie Suggest that the reaction is pseudo first order and the rate of reaction was reduce with rising initial concentration for p-Nitrotolune.


2014 ◽  
Vol 955-959 ◽  
pp. 47-50
Author(s):  
Dan Chen ◽  
Xiao Long Ma

We fabricated new magnetic material CuFe2O4/Zn2Cr-LDH by the combination of CuFe2O4 and layered double hydroxide (LDH) through two steps. CuFe2O4 was prepared by sol-gel method with the assistant of citric acid, which was used in synthesis of the composite via microwave hydrothermal method subsequently. The physicochemical properties of the composite was characterized by several techniques, such as X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Vibrating sample magnetometer (VSM) and Thermogravimetry-differential thermal analysis (TG-DTA). The magnetic composite reveals several advantage of LDH structure and spinel ferrite oxide and is potential for the application of heterogeneous catalysis.


Author(s):  
Hakan Gokmese ◽  
Bulent Bostan

In this study, nanoparticle boron carbide was produced after the reduction of boron oxide with magnesium under the presence of carbon by using mechanochemical synthesis method. During the synthesis processing, microstructure and phase transformations of powders were performed by using X-ray diffraction (XRD), Fourier-transform infrared spectrum (FT-IR), scanning electron microscope (SEM), and high-resolution transmission electron microscopy (HRTEM). At the end of 2 h, reaction products (MgO, B4C) were determined by XRD and FT-IR examinations. Nanoparticle B4C single-phase crystalline structure from the MgO/B4C composite powder mixture, which was the reaction product, was obtained by leaching process. With the increase in the synthesis period, starting material peaks diminished and Fe peak intensity became evident. After the HRTEM examinations, it was determined that synthesized B4C particles were within range of 10–200 nm especially in the activation of leaching process. Additionally, by using spot pattern analysis method, planes represented by B4C particles were calculated.


Sign in / Sign up

Export Citation Format

Share Document