Top PDF Fabrication and characterization of microlasers by the sol-gel method

Fabrication and characterization of microlasers by the sol-gel method

Fabrication and characterization of microlasers by the sol-gel method

deposition and chemical vapor deposition [60, 61]. An alternative route to fabricate silica films is the sol-gel technique. Compared with other methods, the sol-gel method has several advantages: First, it is a versatile technique that involves wet chemical synthesis, therefore the chemical composition of the materials can be stoichiometrically controlled at the molecular level, and the distributions of dopants are homogeneous. Second, it is cost effective due to reaction at low temperature without expensive and delicate vacuum system. This technique allows a wide variety of thin films to be deposited on various substrates. Different optical devices, such as erbium doped waveguide amplifiers (EDWA), one- dimensional photonics crystal devices, microlenses, external-cavity distributed Bragg reflector and size-tunable silica nanocubes have been fabrication by sol-gel or mediated sol-gel methods [62-64]. However, even after heat treatment at high temperature, the loss of the sol-gel materials is still not satisfactory for high-quality optical devices. On the other hand, Lasers have been used to treat the surface of ceramics by melting and re- solidification to produce homogeneous and pore-free surfaces. Herein, we will demonstrate a novel CO 2 laser assisted sol-gel method for fabrication of low loss and low threshold
Show more

113 Read more

Fabrication and Optical Characterization of Zinc Oxide Nanoparticles Prepared via a Simple Sol-gel Method

Fabrication and Optical Characterization of Zinc Oxide Nanoparticles Prepared via a Simple Sol-gel Method

In this research zinc oxide (ZnO) nano-crystalline powders were prepared by sol-gel method using zinc acetate. The ZnO nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis), Fourier transform infra-red (FT-IR) and energy dispersive X-ray (EDX) spectroscopy. The structure of nanoparticles was studied using XRD pattern. The crystallite size of ZnO nanoparticles was calculated by Debye– Scherrer formula. Morphology of nano-crystals was observed and investigated using the SEM. The grain size of zinc oxide nanoparticles were in suitable agreement with the crystalline size calculated by XRD results. The optical properties of particles were studied with UV-Vis an FTIR absorption spectrum. The Raman spectrum measurements were carried out using a micro-laser Raman spectrometer forms the ZnO nanoparticles. At the end studied the effect of calcined temperature on the photoluminescence (PL) emission of ZnO nanoparticles.
Show more

7 Read more

Synthesis and Characterization of Zno - Nanorods by Sol-Gel Method for White LED Phosphors

Synthesis and Characterization of Zno - Nanorods by Sol-Gel Method for White LED Phosphors

IJSRR, 7(4) Oct. – Dec., 2018 Page 1699 Znonanorods phosphors coated on a commercially available blue LED, emitting 480nm emission used for fabrication of white LED .FTIR spectra also studied and reported. Finally the properties of the Zno can be very good

7 Read more

SYNTHESIS AND CHARACTERIZATION OF NICKLE-OXIDE NANOPARTICLES BY SOL-GEL METHOD

SYNTHESIS AND CHARACTERIZATION OF NICKLE-OXIDE NANOPARTICLES BY SOL-GEL METHOD

Nanotechnology is the science of production and use of nanosized materials to produce novel products and processes [1]. Nanomaterials show significantly different properties like mechanical, electronic, magnetic, thermal, catalytic and optical properties as compared to the bulk material, and attracted much interest [2, 3]. Nickel oxide (NiO) already has received much attention due to its excellent electrical, magnetic and catalytic properties [4]. They have wide range of applications in many fields included the fabrication of catalysis [5-7] fuel cell electrodes [8], and gas sensors [9-11], battery cathodes [12-16], magnetic materials [17-20], photovoltaic devices [21], electrochemical supercapacitors [22]. But, most of these applications need particles with a small size and a narrow size distribution.
Show more

5 Read more

SYNTHESIS OF NANOSTRUCTURED MAGNESIUM OXIDE BY SOL GEL METHOD AND ITS CHARACTERIZATION

SYNTHESIS OF NANOSTRUCTURED MAGNESIUM OXIDE BY SOL GEL METHOD AND ITS CHARACTERIZATION

Various fabrication techniques are also employed to synthesize MgO nanoparticles having their own advantages and disadvantages 12 . Spherical shaped magnesium oxide nanoparticles were synthesized successfully by sol-gel method using magnesium nitrate and sodium hydroxide 13 . A sol-gel method is an important technique for the formation of magnesium hydroxide followed by annealing at room temperature to form MgO. After synthesis of MgO nanoparticles, the study of structural, morphological and optical properties was carried out by using techniques such as XRD, FTIR, TEM and UV visible spectroscopy. The present work was aimed to synthesis of MgO nanoparticles chemically and their characterization at room temperature.
Show more

6 Read more

Synthesis And Characterization of Zno-Nanorods By Sol-Gel Method For White Led Phosphors

Synthesis And Characterization of Zno-Nanorods By Sol-Gel Method For White Led Phosphors

IJSRR, 7(4) Oct. – Dec., 2018 Page 1699 Znonanorods phosphors coated on a commercially available blue LED, emitting 480nm emission used for fabrication of white LED .FTIR spectra also studied and reported. Finally the properties of the Zno can be very good

7 Read more

Synthesis, Characterization and Magnetic Properties of Co2+ Substituted Ni Nanoferrite by Sol-Gel Autocombustion Method

Synthesis, Characterization and Magnetic Properties of Co2+ Substituted Ni Nanoferrite by Sol-Gel Autocombustion Method

ratio 1:3 all from Merck co. of purity of 99 % using stoichiometric ratio and dissolved in distilled water. The mixture of the raw material was stirrered at 80 0 C on hot plate magneto-stirrer. Maintaining pH 7, it was continuously stirrered to obtain uniform gel. After 4-5 hours it converts from gel to ash form, which was sintered at 560 0 C. The FTIR characterization shows the bond formation and synthesized material is ferrite. The TGA_DTA characteristics have been taken to determine the temperature range for growth of these systems Differential Thermal Analysis and Thermo Gravimetric Analysis in temperature range 0 0 C -800 0 C was performed. The structural and average grain size is studied by X-ray diffraction (XRD), it is in crystal nature and average particle size is~ 45 to ~15 nm. Particle size decreases with increasing the percentage of Co 2+ . Also lattice constant, (hkl) planes and grain size was calculated by Bragg’s law and Scherer’s formulae. From VSM the magnetic properties of the samples show remarkable changes with change of Co 2+ percentage.
Show more

6 Read more

Preparation and Characterization of Nanocrystalline TiO2 Thin Films Prepared By Sol-Gel Spin Coating Method

Preparation and Characterization of Nanocrystalline TiO2 Thin Films Prepared By Sol-Gel Spin Coating Method

crystallinity and the morphology[4-6].Many methods have been established for titania synthesis such as sol-gel technique [5], hydrothermal method [6],chemical vapour deposition [7,8], direct oxidation method and others[10]. Among them sol-gel technique is one of the most used method due to its possibility of deriving unique metastable structure at low reaction temperatures and excellent chemical homogeneity [11]. In this work we report novel sol-gel spin coated TiO 2 thin film were prepared and the prepared thin films were analyzed.
Show more

5 Read more

Synthesis and Characterization of Nanocrystalline CuNiZn Ferrite Powder Through Sol gel Auto Combustion Method

Synthesis and Characterization of Nanocrystalline CuNiZn Ferrite Powder Through Sol gel Auto Combustion Method

The extensive literature survey reveals that the synthesis of nano –crystalline CuNiZn ferrite powder through sol-gel auto combustion method has been attempted by number of researchers. The temperature at which the ferrite is sintered critically depends on the chemical composition. The electromagnetic properties such as permeability and resistivity are dependent on the densification and microstructure of the ferrite. The application prospects in electronic devices have led to more expensive studies on Ni-Zn ferrites to meet the desired characteristics of electronic component. The Ni-Zn ferrites are widely used in frequency devices for low conductivity and high resistivity.
Show more

9 Read more

Structural and optical characterization of pvp/zno nanocomposites prepared by sol gel dip coating method

Structural and optical characterization of pvp/zno nanocomposites prepared by sol gel dip coating method

The effects of Polyvinlypyrrolidone (PVP) on ZnO thin films prepared by sol-gel dip-coating method were investigated by X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectrometer (FTIR) studies. The optical absorption and transmittance spectra of ZnO thin films have been recorded using UV Spectrophotometer. In addition, the Photoluminescence (PL) has also been obtained to investigate the optical properties of ZnO and PVP/ZnO thin films. The XRD patterns exhibited that, the films were formed in the preferred orientation along c-axis as a function of polyvinylpyrrolidone (PVP) concentration and which also confirms the formation of Wurtzite structure. The crystallite size was calculated using the Scherrer’s formula. The SEM images of ZnO, PVP/ZnO (0.05M) and PVP/ZnO (0.07M) prepared films have depicted a fairly uniform distribution of particle size, such as, 1.2μm, 0.7μm and 1.1μm respectively. The FTIR spectra confirm the presences of ZnO and PVP/ZnO peaks. A remarkable increase in the band gap of PVP/ZnO was observed by UV Spectrophotometric analysis, further it was noticed that, the band gap values were larger than the optical band gap of bulk ZnO material. Whereas,the PL excitation spectra have depicted a strong UV emission and blue emission.
Show more

6 Read more

Characterization of Structural, Optical and Hydrophilicity properties of TiO2 Nano-Powder Synthesized by Sol-Gel Method

Characterization of Structural, Optical and Hydrophilicity properties of TiO2 Nano-Powder Synthesized by Sol-Gel Method

In this paper, titanium dioxide nano-powder was synthesized by sol-gel method in acidic medium. The microstructure, optical band gap, and hydrophilicity of the sample were studied. Optical band gap of titanium dioxide was probed via Diffuse Reflectance Spectra (DRS). Contact angle was measured to investigate hydrophilicity of the powder. XRD analysis was used to study the crystalline structure of the sample. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were also performed. The results showed high crystallinity of the sample with average crystallite size of ~21 nm. Besides, the ratio of anatase to rutile phase demonstrated that the amount of anatase in the sample was seven times greater than that of rutile. The obtained optical band gap for the sample was 3.35 eV with direct linear fitness in Tauc equation. Contact angle (CA) measurements indicated super- hydrophilicity after UV-Radiation for 40 minutes. The results revealed that even though anatase phase was dominant, the existence of rutile phase led to the improvement of both hydrophilicity and photocatalytic properties.
Show more

6 Read more

Synthesis and Characterization of Silver Nanoparticles by Sol-Gel Technique

Synthesis and Characterization of Silver Nanoparticles by Sol-Gel Technique

Nanotechnology is the study, control and manipulation of materials at the nanoscales, typically having dimensions less than 100nm [1]. Nanostructured materials have unique chemical and physical properties, but by their physical application in many fields have stimulated the search for a new synthetic method for material [2]. Metal nanoparticles have been enormously investigated because of their unique optoelectronic properties that are substantially different from bulk materials [3]. Nanoparticles are widely used as its size,

6 Read more

Characterization and Bioactivity of a Quaternary Phosphate-based Glass Powder Synthesized by Sol-Gel Method

Characterization and Bioactivity of a Quaternary Phosphate-based Glass Powder Synthesized by Sol-Gel Method

before and after soaking in SBF for 7 days, are shown in Figure 5a and 5b, respectively. It is interesting to see that the morphology of particles was spherical, and their sizes were smaller than 50 nm (mean particle size of glass powder was about 20 nm (figure 5a). However, sever agglomeration was observed in the glass powder due to its fine size which was relevant to the method that the bioglasses were synthesized from it. Figure 5b shows the surface of the Eth 10 after soaking in SBF

6 Read more

Characterization of organosilica hybrid materials derived from tetraethylorthosilane (teos) and vinyltrimethoxysilane (vtes)  with sol gel Method

Characterization of organosilica hybrid materials derived from tetraethylorthosilane (teos) and vinyltrimethoxysilane (vtes) with sol gel Method

method and development of a calcium phosphate (CP) layer on their surfaces was studied by soaking them in a simulated body fluid (SBF). The rate of in-vitro apatite formation on hybrid surface decreased with increasing the amount of TEOS precursor. The surface morphology of the sample T2 after immersion in SBF for 30 days covered with less precipitation of apatite-like “non-well developed apatite" than T0. These results showed that the best surface in terms of in-vitro bioactivity is the surface of T0 covered with well-developed bone-like apatite. The best surface in terms of bioactivity/thermal stability is the surface of the T2 surface as it contain the both organic and inorganic precursors which both essential for thermal stability as well as bioactivity. For biomaterials application the best surface in terms of in-vitro bioactivity, adsorbed protein amounts and thermal stability is the T2 surface containing VTES: TEOS /1:2.
Show more

7 Read more

SYNTHESIS AND CHARACTERIZATION OF TiO2NANOCRYSTALS BY SOL-GEL METHOD AND TO STUDY THE EFFECT OF CALCINATION TIME ON THE ITS PHOTOCATALYTIC ACTIVITY

SYNTHESIS AND CHARACTERIZATION OF TiO2NANOCRYSTALS BY SOL-GEL METHOD AND TO STUDY THE EFFECT OF CALCINATION TIME ON THE ITS PHOTOCATALYTIC ACTIVITY

The light absorption, the formation rate of hydroxyl radicals, and photocatalyticdecolorization of MB aqueous solution were significantly enhanced for mixed phase instead of simple anata[r]

6 Read more

Synthesis and Characterization of Nitrogen Doped with Titanium Dioxide at Different Calcination Temperature by using Sol-Gel Method

Synthesis and Characterization of Nitrogen Doped with Titanium Dioxide at Different Calcination Temperature by using Sol-Gel Method

In photocatalytic process of dye, some parameters that influence the effectiveness of the activity are pH of the dyes, initial concentration of substrates/wastewater, calcination temperature during the preparation of photocatalyst, amount of catalyst and also the method used to prepare the photocatalyst. In the attempt to make sure the dyes removal process at higher efficiency, faster and convenient to conduct, it is necessary to specify the impact of each element that will give impact to the degradation of dyes [7].

7 Read more

Preparation and Characterization of High Specific Surface Area γ-Alumina Nanoparticles Via Sol-Gel Method

Preparation and Characterization of High Specific Surface Area γ-Alumina Nanoparticles Via Sol-Gel Method

Preparation of γ-alumina nanoparticles was done via sol-gel method with cheap and high purity raw materials and without environmental pollution. Aluminum isopropoxide alkoxide was used as aluminum precursor instead of aluminum inorganic salts which produces γ- alumina powder with a higher specific surface area. This material is cheaper and easily available compared to many other alkoxides such as tri-sec-butoxide aluminum. Aluminum isopropoxide (AIP, Al(OCH(CH 3 )CH 3 ) 3 , >98.0 wt%, MERCK Art. No.

8 Read more

Synthesis and Characterization of Sc and Y Co-doped Zirconia (Zr0.84Y0.08Sc0.08O1.92) Electrolyte Prepared by Sol-Gel Method

Synthesis and Characterization of Sc and Y Co-doped Zirconia (Zr0.84Y0.08Sc0.08O1.92) Electrolyte Prepared by Sol-Gel Method

Renz Marion G. Garcia received his undergraduate degrees in Chemistry, and Materials Science and Engineering from Ateneo de Manila University. He completed his M.S. in Materials Science and Engineering at the University of the Philippines Diliman in 2018. He is currently working in the GREENPower project of the Energy Storage and Conversion Materials research laboratory under the supervision of Asst. Prof. Rinlee Butch Cervera. His research interests include development and characterization of electrode and electrolyte materials for solid oxide electrochemical cells.
Show more

7 Read more

FABRICATION AND CHARACTERIZATION OF ITRACONAZOLE LOADED NANOSPONGE GEL

FABRICATION AND CHARACTERIZATION OF ITRACONAZOLE LOADED NANOSPONGE GEL

50 mg from the prepared drug loaded Nanosponges by emulsion solvent diffusion method using suitable polymer were suspended in 50 ml of methanol and were subjected for ultracentrifugation for 40 minutes. The percentage of incorporated itraconazole was determined spectrophotometrically at 259nm. After centrifugation of the aqueous suspension, amount of free drug was detected in the supernatant and the amount of incorporated drug was determined as a result of the initial drug minus the free drug. The drug entrapment efficiency (EE) of itraconazole Nanosponges [25] was determined using the formula,
Show more

21 Read more

Investigation of the Sol-Gel Method on the Flexible ZnO Device

Investigation of the Sol-Gel Method on the Flexible ZnO Device

Currently, most ZnO thin films are deposited by using chemical vapor deposition (CVD) and physical vapor deposition (PVD) methods. CVD and PVD often require a high-vacuum and high- temperature environment, and thus, do not work for flexible electronic roll-to-roll processes integrated for ZnO thin-film deposition. In contrast, the sol-gel method of channel layers offers advantages in enabling the fabrication of a flexible transistor including low cost, low temperature, easy control of deposition parameters, compatibility with large area depositions, and an ability to operate at atmospheric pressure [7, 8, 9, 10, 11].
Show more

10 Read more

Show all 10000 documents...