Band Gap Energies of Magnesium Oxide Nanomaterials Synthesized by the Sol-Gel Method

2012 ◽  
Vol 545 ◽  
pp. 157-160 ◽  
Author(s):  
Nurhanna Badar ◽  
Nor Fadilah Chayed ◽  
Rusdi Roshidah ◽  
Norashikin Kamarudin ◽  
Norlida Kamarulzaman
Keyword(s):  
Band Gap ◽  
Magnesium Oxide ◽  
Sol Gel ◽  
Nir Spectroscopy ◽  
Band Gap Energy ◽  
Heating Time ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method

In this work, the band gap energies of magnesium oxide (MgO) were investigated to see if calcination time affects the band gap energies of the MgO. MgO nanomaterials have been prepared by a sol-gel method. MgO precursors produced were calcined at a temperature of 600 °C for 24 hours and 48 hours. The structural characterization of samples is achieved using X-Ray Diffraction (XRD) and the morphology as well as particle size of MgO were examined by Field Emission Scanning Electron Microscopy (FESEM). UV-Vis NIR spectroscopy was used to determine the band gap energies of the materials. From the results, the band gap energy of the MgO with a longer heating time exhibited a higher value.

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

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.

CONTROLLED SYNTHESIS AND CHARACTERIZATION OF TiO2 NANOPARTICLES VIA A SOL–GEL METHOD

2004 ◽  
Vol 03 (06) ◽  
pp. 749-755 ◽  
Author(s):  
YING LI ◽  
SUO HON LIM ◽  
TIM WHITE
Keyword(s):  
Sol Gel ◽  
Critical Role ◽  
Rietveld Analysis ◽  
Nanocrystalline Powders ◽  
X Ray Diffraction ◽  
Gelation Temperature ◽  
Gel Method ◽  
Sol Gel Method ◽  
Transmission Electron

The properties influencing the photocatalytic activity of TiO 2 particles have been suggested to include the surface area, crystallinity, crystallite size and crystal structure. Therefore, manipulation of the microstructure of titania, especially of nanocrystalline powders, is very important in the preparative process. In this study, nanocrystalline TiO 2 powders with controlled particle size and phase composition were synthesized at low temperature (<80°C) by a modified sol–gel method. The effects of gelation temperature were systematically investigated. It was found that this parameter played a critical role in determining the crystallinity of single phase anatase. With increasing gelation temperature, the crystallinity of anatase improved initially and then decreased if the temperature was raised to 80°C. These nanomaterials were characterized comprehensively by powder X-ray diffraction (including Rietveld analysis), high-resolution transmission electron microscopy, DSC/TGA thermal analysis and UV–Vis spectrometry.

Synthesis and Characterization of Fluorine-Doped Tin Oxide Nanocrystals Prepared by Sol-Gel Method

2014 ◽  
Vol 977 ◽  
pp. 59-62 ◽  
Author(s):  
Jun Qing Tian ◽  
Hai Ying Shi ◽  
Wei Zheng
Keyword(s):  
Tin Dioxide ◽  
Sol Gel ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Hall Effect Sensor ◽  
Precursor Material ◽  
20 Nm

Fluorine-doped tin dioxide (FTO) nanocrystals were prepared with sol–gel method using SnCl4·5H2O and NH4F as precursor material. The FTO was characterized with X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Differential Thermal Analysis and Thermal Grativity (DTA-TG) and Infrared Radiation (IR) respectively. The electrical property was measured with Hall Effect Sensor. The result of XRD and SEM shows that FTO nanocrystal size is about 20 nm and the dimension of the grain is about 300 nm. IR spectrum analysis proves fluorine doping. The crystal phase transformation was discussed with DTA-TG curve. When the sintering temperature is 450°C, the sintering time is 60 min, and the molar ratio of F to Sn is 2:10, the sheet resistance of FTO film is 107Ω/□.

Preparation and Characterization of Li4/3Ti5/3O4 Thin Films by Sol-gel Method

2006 ◽  
Vol 972 ◽  
Author(s):  
C. Hu ◽  
W. Zhang ◽  
H. Hao ◽  
M. H. Cao ◽  
S. J. Lai ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Sol Gel ◽  
High Capacity ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Atomic Force ◽  
Good Crystallinity

AbstractIn the study Li4/3Ti5/3O4 thin films were deposited on Pt substrates by sol-gel method using a spin coator. The coated films are dried at 310-360 °C, and then annealed at 500-800 °C for 30min. The prepared films were characterized by X-ray diffraction, atomic force microscope and scanning electron microscope. The results indicated that the prepared film belonged to a spinel structure and had a uniform morphology. Electrochemical properties of the prepared electrode films were evaluated by using a discharge and charge test. From these results, it can be showed that the thin film electrode annealed at 700 °C exhibited good crystallinity, smooth surface morphology, high capacity, and good rechargeability. Therefore, This film was therefore suitable for use as an anode for thin-film microbatteries.

Synthesis and characterization of magnesium Oxide nanoparticles by sol-gel method

2020 ◽  
Vol 3 (3) ◽  
Author(s):  
Jegadeeswari A ◽  
Nivetha S
Keyword(s):  
Magnesium Oxide ◽  
Sol Gel ◽  
Morphological Characterization ◽  
Magnesium Nitrate ◽  
Oxide Nanoparticles ◽  
Mgo Nanoparticles ◽  
Gel Method ◽  
Sol Gel Method ◽  
Magnesium Oxide Nanoparticles

Magnesium oxide was hygroscopic solid mineral that occurs naturally as periclase.Magnesium oxide had high thermal conductivity; it gets heated when the electricity was passed through it. Magnesia crucible had a stability of 2400°C in air, 1700°C in reducing atmosphere. Magnesium oxide nanoparticles were obtained from the mixture of magnesium nitrate as precursor and sodium hydroxide as precipitating agent by sol-gel method. Finally,the resultant white crystalline powder of MgO was annealed at various temperatures of 80°C, 135°C and 180°C. The analytical studies (XRD, SEM FTIR, EDAX) reveals the morphological characterization of MgO nanoparticles. The Scanning Electron Microscopy (SEM) indicates the structures of MgO nanoparticles. The crystal size of MgO nanoparticles was obtained by X-Ray Diffraction (XRD). The optical properties of the sample were obtained by UV- Visible spectroscopy. Fourier Transform infrared spectroscopy indicates powdered composition of the sample. EDAX indicates elementary composition of the MgO nanoparticles.

Structure and magnetic characterization of Sr-doped BiFeO3 prepared by sol–gel method

2021 ◽  
pp. 2150205
Author(s):  
Haiwen Chen ◽  
Shengli Hu ◽  
Ge Zhang ◽  
Zhengming Jiang ◽  
JiaJun Mo ◽  
...  
Keyword(s):  
Oxygen Vacancy ◽  
Sol Gel ◽  
Magnetization Measurement ◽  
Impurity Phase ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Cubic Structure

Multiferroic nanocrystalline Bi[Formula: see text]Sr[Formula: see text]FeO3 ([Formula: see text], 0.05, 0.1) samples were synthesized using the sol–gel method and characterized by powder X-ray diffraction, Mössbauer spectroscopy and SQUID system. The small-angle X-ray diffraction analysis showed that the sample underwent phase transition from rhombohedral to pseudo-cubic structure with the enhancement of Sr content. In addition, impurity peaks gradually diminished, indicating that content of impurities of samples reduced. Furthermore, it can be determined that there is only Fe[Formula: see text] in all the samples and impurity phase that existed in the samples was Bi[Formula: see text]FeO[Formula: see text] by fitting Mössbauer spectra. It is further confirmed that Bi[Formula: see text] Sr[Formula: see text]FeO3 samples were generated by oxygen vacancy equilibrium valence state when Sr[Formula: see text] ions replaced Bi[Formula: see text] ions. The change of quadrupole splitting indicated that a low concentration of Sr[Formula: see text] ions diffused homogeneously in the sample. Magnetization measurement showed that the magnetization of the sample increased gradually with the substitution of Bi[Formula: see text] by nonequivalent Sr[Formula: see text] ions, which can be ascribed to the decrease of grain size and the increase of oxygen vacancy and specific surface in the samples.

Synthesis and Characterization of LiZn Ferrites/Carbon Nanotubes (CNTs) Temperature Control Biomaterials

2016 ◽  
Vol 680 ◽  
pp. 189-192
Author(s):  
Zhao Jun Liu ◽  
Kang Ning Sun ◽  
Ai Min Li ◽  
Xiao Ning Sun ◽  
Shu Pin Zhang
Keyword(s):  
Electron Microscope ◽  
Temperature Control ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Transmission Electron ◽  
Subsequent Calcination ◽  
Different Content

In this study, LiZn ferrites with different content of CNTs (1%-9%) were successfully prepared by a sol-gel method. X-ray diffraction pattern exhibit a relatively high crystallinity of the Li0.25Zn0.5Fe2.25O4/CNTs composite, and the CNTs still exist after acid treatment and subsequent heat treatment. Then the composite was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM), the results demonstrate that the particles are nearly spherical in shape and agglomerated to some extent. By a sol-gel method and subsequent calcination, the temperature of LiZn ferrites/CNTs temperature control biomaterials gradually increase and maintain at a certain temperature in the alternating magnetic field, so it can be a potential material used for hyperthermia applications.

Preparation and Characterization of Cr2O3 Nano-Powders by Sol-Gel Method

2007 ◽  
Vol 353-358 ◽  
pp. 2111-2114 ◽  
Author(s):  
Chun Cheng Zhu ◽  
Yan Hong ◽  
Jian Guang Zhang ◽  
Bai Bin Zhou
Keyword(s):  
Aqueous Ammonia ◽  
Sol Gel ◽  
Chromium Nitrate ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Xrd Techniques ◽  
Differential Thermogravimetry

Cr2O3 nano-powders were successfully fabricated with using chromium nitrate and aqueous ammonia as starting material and urea as dispersant agent by sol-gel method. The formation of crystalline phase during heat treatment of dry gel was characterized by differential thermogravimetry (DTG) and X-ray diffraction (XRD) techniques and the temperature of calcination was determined as 400°C. Scanning electron microscopy (SEM) was utilized to observe the morphology of the as-fabricated Cr2O3 particles. The results showed that Cr2O3 particles are spherical or square with little agglomeration and a diameter of about 30 nm. The specific surface area of Cr2O3 particles was measured as 44.23 m2/g by Brunauer-Emmett-Teller (BET).

scholarly journals Synthesis and Characterization of Strontium Oxide Nano Particle by Sol-Gel Method

2021 ◽  
Vol 37 (1) ◽  
pp. 177-180
Author(s):  
Alimuddin Alimuddin ◽  
Mohd Rafeeq
Keyword(s):  
Room Temperature ◽  
Sol Gel ◽  
Oxide Nanoparticles ◽  
Strontium Nitrate ◽  
Strontium Oxide ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method

Synthesis of strontium oxide nanoparticles was carried out by sol –gel method using strontium nitrate and sodium hydroxide at room temperature which is very simple and cost effective. The characterization of strontium oxide nanoparticles was done using X-ray diffraction, scanning electron microscopy (SEM) and Fourier transform infra-red (FTIR). X-ray diffraction pattern indicates that the nanoparticles are crystalline in nature. The crystalline size of strontium oxide nanoparticle was calculated by Debye-Scherrer formula. The crystalline sizes are about 80nm. The morphology of nanoparticles was observed and investigated using SEM. The material at room temperature, calcined at 2000C, 400 0C and 6000C respectively shows pseudo spherical shape, cubic form and finally it becomes cylindrical this shows that there is a agglomeration with increase in temperature. FTIR spectrum of strontium oxide shows the peak at 854.64 cm-1 which is due to Sr -O bond.

Study of Titanium Dioxide Thin Film by Sol-Gel Method

2014 ◽  
Vol 925 ◽  
pp. 278-281 ◽  
Author(s):  
Sharipah Nadzirah ◽  
Uda Hashim ◽  
N. Malihah
Keyword(s):  
Thin Film ◽  
Titanium Dioxide ◽  
Spin Coating ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method

Titanium dioxide (TiO2) thin films based interdigitated electrodes (IDEs) have been synthesized using sol-gel method with hydrochloric acid (HCl) as catalyst. The prepared TiO2 solution has been deposited onto silicon dioxide (SiO2) substrates via spin-coating technique. Film was annealed at 500 °C and aluminium (Al) IDEs have been fabricated. Finally the X-ray diffraction (XRD) shows high intensity of both anatase and rutile peaks exist on 10 nm TiO2 thin film. Average crystallite size of the nanoparticles is seen to be 25 nm. UvVisible spectroscopic (UvVis) technique was used for the transmittance spectra characterization of the sample.

Sign in / Sign up

Export Citation Format

Share Document