Analysis of the Structure and Morphology of Hydroxyapatite Nanopowder Obtained by Sol-Gel and Pirosol Methods

2012 ◽  
Vol 590 ◽  
pp. 63-67 ◽  
Author(s):  
Rodica Rogojan ◽  
Ecaterina Andronescu ◽  
Cristina Ghitulica ◽  
Mihaela Birsan ◽  
Georgeta Voicu ◽  
...  

Nano-size hydroxyapatite is the main inorganic component of bone. There is a critical particle size that each property starts to change. Each property can be modified under controlled conditions. Multifunctional materials for applications, one must consider several properties change. Bone properties, are those which dictate the properties of hydroxyapatite, properties to be followed the synthetic materials to be used successfully as implants. Of these mention those related to surface materials, solubility and biocompatibility and their mechanical strength. Depending on the location and functionality of the implant have met some of these properties. The purpose of this study is to develop a synthetic hydroxyapatite at nano scale, using sol-gel and pyrosol method, for its use in medicine

2010 ◽  
Vol 177 ◽  
pp. 25-28
Author(s):  
Bao Rang Li ◽  
Bin Cao ◽  
Cong Lu

Bismuth titanate nano-crystals were prepared successfully by sol-gel method and the critical particle size for phase transition was analyzed by Raman techniques. The results revealed the new Raman peaks at the wave number about 87, 227, 442, 467, 577 and 617cm-1 discerned gradually with increasing the particle size and abrupt increase in integrated intensity ratios of these modes, companied with strong decrease of half-widths happened at the particle size ranging from 18 to 33nm, which suggested an obvious size driven tetragonal-to-orthorhombic phase transition in Bismuth titanate nano-crystals.


2007 ◽  
Vol 544-545 ◽  
pp. 797-800
Author(s):  
Kun Ho Song ◽  
Byoung Moon Kim ◽  
Jeong Eun Kim ◽  
Kwang Rae Lee

The nano-size PbTiO3 particles were prepared by sol-gel method and the effects of processing variables such as concentration of sol solution, catalyst, concentration of catalyst, calcination temperature and calcination process on particle size of PbTiO3 were analyzed. The condition for preparation of sol solution from the precursor is very critical to the size of PbTiO3 particle. At certain experimental conditions, the particles of 129nm, 213nm and 343nm were obtained. However, the particle size of commercialized PbTiO3 powder was 5㎛(5,000nm). The prepared nano-size PbTiO3 powder adsorbed more acetic acid and formic acid than the commercialized one; 1.5 times for acetic acid and 1.2 times for formic acid. Formic acid was preferentially adsorbed than acetic acid.


2021 ◽  
Vol 2114 (1) ◽  
pp. 012076
Author(s):  
Falah H Ali

Abstract Nano-structure SiO2 was prepared in this work by use Sol-Gel method. Then, studying optical and structural properties of SiO2, the absorption spectrum was determined in UV region, while nano-structure and morphology was investigated by XRD and AFM respectively. The particle size measured by use AFM Analysis which about (55.12 nm).super hydrophilic was gotten after 1 hour of UV irradiation for the prepared SiO2 thin-film.


2016 ◽  
Vol 852 ◽  
pp. 238-243 ◽  
Author(s):  
Shi Guang Shang ◽  
Xin Li ◽  
Ling Zhao ◽  
Rui Lu ◽  
Hai Feng Chen

Titanium dioxide (TiO2) nanoparticles were synthesized by sol-gel method and the influences of calcination temperature and pH level on the particle size, crystal structure and morphology of the TiO2 nanoparticles were investigated. X-ray diffraction patterns reveal that the anatase to rutile phase transition occurs at calcination temperature varying from 600°C to 800°C and the phase transformation temperature obviously decreases as the pH level of reaction solution decreases. Scanning electron microscopy images show that pH level and calcination temperature play an important role in controlling the particle size, crystal structure and morphology of the as-prepared TiO2 nanoparticles. The gas sensing properties of Ag-doped TiO2 nanoparticles were measured and the experimental results exhibit that the gas sensor based on Ag-doped TiO2 nanoparticle film has high sensitivity and fast response to ethanol.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3876
Author(s):  
Jesús Valdés ◽  
Daniel Reséndiz ◽  
Ángeles Cuán ◽  
Rufino Nava ◽  
Bertha Aguilar ◽  
...  

The effect of microwave radiation on the hydrothermal synthesis of the double perovskite Sr2FeMoO6 has been studied based on a comparison of the particle size and structural characteristics of products from both methods. A temperature, pressure, and pH condition screening was performed, and the most representative results of these are herein presented and discussed. Radiation of microwaves in the hydrothermal synthesis method led to a decrease in crystallite size, which is an effect from the reaction temperature. The particle size ranged from 378 to 318 nm when pH was 4.5 and pressure was kept under 40 bars. According to X-ray diffraction (XRD) results coupled with the size-strain plot method, the product obtained by both synthesis methods (with and without microwave radiation) have similar crystal purity. The Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) techniques showed that the morphology and the distribution of metal ions are uniform. The Curie temperature obtained by thermogravimetric analysis indicates that, in the presence of microwaves, the value was higher with respect to traditional synthesis from 335 K to 342.5 K. Consequently, microwave radiation enhances the diffusion and nucleation process of ionic precursors during the synthesis, which promotes a uniform heating in the reaction mixture leading to a reduction in the particle size, but keeping good crystallinity of the double perovskite. Precursor phases and the final purity of the Sr2FeMoO6 powder can be controlled via hydrothermal microwave heating on the first stages of the Sol-Gel method.


2013 ◽  
Vol 634-638 ◽  
pp. 2150-2154 ◽  
Author(s):  
Rita Sundari ◽  
Tang Ing Hua ◽  
M. Rusli Yosfiah

A citric acid anionic surfactant has been applied for nano manganese ferrite (MnFeO3) fabrication using sol gel method. The calcinations have been varied for 300, 600 and 800oC. The UVDR (UV-Vis Diffused Reflectance) analysis shows a high absorptive band gap after 400 nm for the 600oC calcinated MnFeO3. The DTA (Differential Thermal Analysis) profiles exhibit remarkably trapped volatile matters (H2O, CO2, and NO2) in the fabricated MnFeO3 under sol gel heat treatment at 100oC and the peaks disappeared as the calcination increased to 600oC. As the temperature elevated from 100 to 300oC, the absorption peaks of volatile components are disappeared as demonstrated clearly by the FTIR (Fourier Transform Infrared) spectra of the fabricated material, which 3393 cm-1 corresponded to OH group, 1624 cm-1 to CO group, and 1384 cm-1 to NO group. The XRD (X-Ray Diffraction) spectra show clearly the alteration process from amorphous to crystalline structure as the calcinations increased from 300 to 600oC. In addition, the TEM (Transmission Electron Microscope) analysis exhibits parts of the fabricated MnFeO3 found in cubic nano size of 15-40 nm under interested calcinations and the result is in agreement with that obtained by XRD investigation.


2013 ◽  
Vol 756 ◽  
pp. 91-98 ◽  
Author(s):  
Ftema W. Aldbea ◽  
Noor Bahyah Ibrahim ◽  
Mustafa Hj. Abdullah

Terbium –substituted yttrium iron garnet (Tb1.5Y1.5Fe5O12) films nanoparticles were successfully prepared by a sol-gel method. The films were deposited on the quartz substrate using spin coating technique. To study effect of annealing temperature, the annealing process was executed at 700, 800 and 900 °C in air for 2 hours. The X-ray diffraction (XRD) proved that the pure phase of garnet structure was detected for the film annealed at 900 °C. The lattice parameter increased with the increment of annealing temperature and the highest value of 12.35 Å was obtained at 900 °C. Field Emission Scanning Electron Microscope (FE-SEM) results showed that the particle size increased from 43nm to 56nm as annealing temperature increased from 700 to 900°C. The film’s thickness also affected by increasing of annealing temperature and become thin at 900 °C due to densification process occurred at high annealing temperature. The elemental compositions of the Tb1.5Y1.5Fe5O12 film were detected using an Energy Dispersive X-raySpectroscopy (EDX). Magnetic properties at room temperature were measured using a Vibrating Sample Magnetometer (VSM).The saturation magnetization Ms increased with the annealingtemperature and showed a high value of 104emu/cm3, but the coercivity Hc of the film was decreased due to the increment of the particle size. Normal 0 21 false false false MS X-NONE X-NONE MicrosoftInternetExplorer4 Terbium –substituted yttrium iron garnet (Tb1.5Y1.5Fe5O12) films nanoparticles were successfully prepared by a sol-gel method. The films were deposited on the quartz substrate using spin coating technique. To study effect of annealing temperature, the annealing process was executed at 700, 800 and 900°C in air for 2 hours. The X-ray diffraction (XRD) proved that the pure phase of garnet structure was detected for the film annealed at 900 °C. The lattice parameter increased with the increment of annealing temperature and the highest value of 12.35 Å was obtained at 900 °C. Field Emission Scanning Electron Microscope (FE-SEM) results showed that the particle size increased from 43nm to 56nm as annealing temperature increased from 700 to 900 °C. The film’s thickness also affected by increasing of annealing temperature and become thin at 900 °C due to densification process occurred at high annealing temperature. The elemental compositions of the Tb1.5Y1.5Fe5O12 film were detected using an Energy Dispersive X-ray Spectroscopy (EDX). Magnetic properties at room temperature were measured using a Vibrating Sample Magnetometer (VSM).The saturation magnetization Ms increased with the annealing temperature and showed a high value of 104emu/cm3, but the coercivity Hc of the film was decreased due to the increment of the particle size. st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}


2008 ◽  
Vol 62 (6-7) ◽  
pp. 837-839 ◽  
Author(s):  
Xiangwei Wu ◽  
Zhaoyin Wen ◽  
Bin Lin ◽  
Xiaogang Xu
Keyword(s):  
Sol Gel ◽  

2003 ◽  
Vol 17 (01) ◽  
pp. 19-24 ◽  
Author(s):  
K. PADMAVATHI ◽  
V. RAJAKUMARI ◽  
M. VITHAL ◽  
V. PRASD ◽  
S. V. SUBRAMANYAM ◽  
...  

A series of colossal magneto resistance materials having compositional formula Re 0.67 Sr 0.33 MnO 3 (Re = Nd, Gd, … etc.) were prepared by the sol-gel method, using Ethylene glycol as a gelating reagent. The materials were characterized by the powder X-ray diffraction technique and are found to be single phase with orthorhombic structure. The particle size of all the materials were calculated using the well known Shearer formula and are found to be in the range of 20–45 nm. In order to determine the transition temperature (T c ), the DC electrical resistivity measurements were also carried out over a temperature range 80–300 K using the four probe method and it has been observed that the T c values are found to increase with increasing ionic size. Finally the magneto resistance measurements were also undertaken in the temperature range 80–300 K and it has been found that the MR values of these materials are better when compared with those prepared by the solid state reaction method.


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