Investigation on the Correlations between Droplet and Particle Size Distribution in Ultrasonic Spray Pyrolysis

2008 ◽  
Vol 47 (5) ◽  
pp. 1650-1659 ◽  
Author(s):  
Wei-Ning Wang ◽  
Agus Purwanto ◽  
I. Wuled Lenggoro ◽  
Kikuo Okuyama ◽  
Hankwon Chang ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Spray Pyrolysis ◽  
Size Distribution ◽  
Ultrasonic Spray Pyrolysis ◽  
Ultrasonic Spray

scholarly journals New Proposal for Size and Size-Distribution Evaluation of Nanoparticles Synthesized via Ultrasonic Spray Pyrolysis Using Search Algorithm Based on Image-Processing Technique

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 38 ◽  
Author(s):  
Elif Emil Kaya ◽  
Ozan Kaya ◽  
Gözde Alkan ◽  
Sebahattin Gürmen ◽  
Srecko Stopic ◽  
...  
Keyword(s):  
Image Processing ◽  
Particle Size ◽  
Spray Pyrolysis ◽  
Size Distribution ◽  
Search Algorithm ◽  
Ultrasonic Spray Pyrolysis ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Sem Micrographs ◽  
Ultrasonic Spray

Nanoparticle properties are correlated to their size, size distribution, and shape; it is essential to accurately measure these features in the field of nanoscience. In this study, silver nanoparticles (AgNPs) were synthesized with the ultrasonic-spray-pyrolysis (USP) method from a water solution of silver nitrate. The synthesized AgNPs were characterized by Dynamic Light Scattering (DLS) analysis and Scanning Electron Microscopy (SEM) to reveal their size and size distribution. A search algorithm based on an image-processing technique to obtain particle size and particle-size distribution from SEM micrographs is proposed. In order to obtain more quantitative information and data with respect to the morphology of particles synthesized under different process parameters, SEM micrographs with a nonhomogeneous background contrast were examined via image-processing techniques in MATLAB. Due to the inhomogeneous contrast of SEM micrographs, defining an overall threshold value was insufficient in the detection of whole nanoparticles. Thus, subimages were directly created according to the maximum and minimum particle size specified by the user to determine local threshold values. The obtained results were automatically combined to represent both particle dimension and location in the SEM micrographs. We confirmed that the results of our DLS analysis, theoretical calculation, and image-processing technique were correlated with our expected results.

Formation of Non-Toxic Au Nanoparticles with Bimodal Size Distribution by a Modular Redesign of Ultrasonic Spray Pyrolysis

2015 ◽  
Vol 7 (11) ◽  
pp. 920-929 ◽  
Author(s):  
Peter Majerič ◽  
Darja Jenko ◽  
Bojan Budič ◽  
Sergej Tomić ◽  
Miodrag Čolić ◽  
...  
Keyword(s):  
Spray Pyrolysis ◽  
Size Distribution ◽  
Au Nanoparticles ◽  
Ultrasonic Spray Pyrolysis ◽  
Bimodal Size Distribution ◽  
Ultrasonic Spray

scholarly journals Undoped and Nickel-Doped Zinc Oxide Thin Films Deposited by Dip Coating and Ultrasonic Spray Pyrolysis Methods for Propane and Carbon Monoxide Sensing Applications

Sensors ◽  
2020 ◽  
Vol 20 (23) ◽  
pp. 6879
Author(s):  
Tangirala Venkata Krishna Karthik ◽  
María de la Luz Olvera ◽  
Arturo Maldonado ◽  
Rajesh Roshan Biswal ◽  
Heberto Gómez-Pozos
Keyword(s):  
Thin Films ◽  
Carbon Monoxide ◽  
Zinc Oxide ◽  
Spray Pyrolysis ◽  
Size Distribution ◽  
Ultrasonic Spray Pyrolysis ◽  
Dip Coating ◽  
Zno Films ◽  
Ultrasonic Spray ◽  
Deposition Techniques

Undoped and nickel-doped zinc oxide thin films were deposited on sodalime glass substrates by utilizing dip coating and ultrasonic spray pyrolysis deposition techniques. In both cases zinc acetate and nickel acetylacetonate were used as zinc precursor and nickel dopant source, respectively. XRD analysis confirms the ZnO wurtzite structure with (002) as the preferential orientation.SEM studies show the formation of two types of morphologies, primarily a porous spherical grains with a grain size distribution from 40 to 150 nm and another, rose-like structures with size distribution from 30 to 200 nm, based on different deposition techniques utilized. The elemental depth profiles across the films were investigated by the secondary-ion mass spectrometry (SIMS). Different gas sensing responses of all ZnO films were obtained for both propane and carbon monoxide gases, at different gas concentrations and operating temperatures. The highest sensing response (~6) for undoped ZnO films was obtained for films deposited by ultrasonic spray pyrolysis (USP). Nevertheless, the highest sensing response (~4 × 104) for doped ZnO films was obtained for films deposited by dip coating method. The behavior of sensing responses is explained in detail based on the morphological properties and the amount of Ni impurities incorporated into the crystal lattice.

Synthesis and Characterization of Li(Ni1/3Mn1/3Co1/3)O2 Nano-Particle by Aerosol Plasma Pyrolysis

2006 ◽  
Vol 320 ◽  
pp. 255-258 ◽  
Author(s):  
Kenichi Myoujin ◽  
Takashi Ogihara ◽  
Nobuo Ogata ◽  
Koji Nakane ◽  
Takayuki Kodera ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Ultrasonic Spray Pyrolysis ◽  
Metal Nitrate ◽  
Superior Performance ◽  
Pyrolysis Process ◽  
Cycle Number ◽  
Bet Analysis ◽  
Plasma Pyrolysis

Spherical LiNi1/3Mn1/3Co1/3O2 precursor powders were synthesized by aerosol plasma pyrolysis using aqueous solution of metal nitrate. XRD, SEM, TEM and BET analysis were used for determi- nation of the composition, morphology, particle size and surface area. SEM observation showed that the size of as-prepared particles were about 200 nm. The value of geometrical standard deviation (σg) calculated from the particle size distribution was 1.20, suggesting that the particle size distribution was narrow. The crystal phase of LiNi1/3Mn1/3Co1/3O2 was resulted in layered rock salt structure with R3m space group. The rechargeable capacity of LiNi1/3Mn1/3Co1/3O2 was about 142-175 mAh/g. The discharge capacity of LiNi1/3Mn1/3Co1/3O2 decreased with increasing cycle number. However, the cycling stability of Li(Ni1/3Mn1/3Co1/3)O2 powders that aerosol plasma pyrolysis process offered superior performance to ultrasonic spray pyrolysis process.

Electrochemical Properties of Al Doped Li(Ni1/3Co1/3Mn1/3)O2

2007 ◽  
Vol 124-126 ◽  
pp. 1023-1026 ◽  
Author(s):  
Seon Hye Kim ◽  
Kwang Bo Shim ◽  
Kyoung Ran Han ◽  
Chang Sam Kim
Keyword(s):  
Heat Treatment ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Ultrasonic Spray Pyrolysis ◽  
Lithium Ion ◽  
Initial Discharge Capacity ◽  
Cycle Stability ◽  
Al Doping ◽  
Ultrasonic Spray ◽  
Initial Discharge

Al doped Li(Ni1/3Co1/3Mn1/3-xAlx)O2 (x=0.005, 0.01, 0.05) and Li(Ni1/3-x/2Co1/3Mn1/3-x/2Alx)O2 (x=0.01, 0.05) cathode materials for lithium ion batteries were synthesized using an ultrasonic spray pyrolysis and heat treatment. The substitution with Al reduced the content of Mn3+, promoted grain growth, and broadened the particle size distribution of synthesized powders. The initial discharge capacity of cells made with 0.5 mol% Al doped Li(Ni1/3Co1/3Mn1/3-0.005Al0.005)O2 powder was as high as that of the undoped (~180 mAhg-1, 3.04.5 V), and showed an excellent cycle stability. The improvement of the cycle stability was considered to be due to the decrease of Mn3+ in Li(Co1/3Ni1/3Mn1/3-xAlx)O2 by Al doping.

scholarly journals Microstructure and Sintering Behavior of Fine Tungsten Powders Synthesized by Ultrasonic Spray Pyrolysis

2021 ◽  
Vol 59 (5) ◽  
pp. 289-294
Author(s):  
Hyeonhui Jo ◽  
Jeong Hyun Kim ◽  
Young-In Lee ◽  
Young-Keun Jeong ◽  
Sung-Tag Oh
Keyword(s):  
Particle Size ◽  
Relative Density ◽  
Spray Pyrolysis ◽  
Spark Plasma Sintering ◽  
Hydrogen Reduction ◽  
Ultrasonic Spray Pyrolysis ◽  
Sintering Behavior ◽  
Ultrasonic Spray ◽  
Plasma Sintering ◽  
Spark Plasma

The powder microstructure and sintering behavior of W prepared by ultrasonic spray pyrolysis and spark plasma sintering were investigated. Fine-grained W powders were synthesized by ultrasonic spray pyrolysis using an ammonium metatungstate hydrate solution and hydrogen reduction. The XRD analysis of the powder, pyrolyzed below 600 oC, showed tungsten oxide hydrate and WO3 peaks, while the powder pyrolyzed at 700 oC was composed of only the WO3 phase. As the precursor concentration increased, the particle size of the WO3 powder increased, which was interpreted to be due to an increase in the amount of solute in the droplet. The hydrogen-reduced powder showed a spherical shape with fine pores inside. XRD and XPS analysis revealed that the WO3 powder was completely reduced to metallic W by hydrogen reduction, and some oxide layers existed on the powder surface. The consolidated specimen prepared by spark plasma sintering of hydrogen-reduced W powder exhibited a relative density of 94.1% and a Vickers hardness value of 3.89 GPa. The relative density and hardness of the specimens prepared by ultrasonic spray pyrolysis showed relatively lower values than when commercial W powder, with an average particle size of 1.22 μm, was sintered under the same conditions. These results were explained by the formation of agglomerates in the W powder prepared by the ultrasonic spray pyrolysis method.

Effects of Different Salts on Salt-Assisted Ultrasonic Spray Pyrolysis (SA-USP) Calcination for the Synthesis of Strontium Ferrite

2015 ◽  
Vol 15 (10) ◽  
pp. 8062-8069 ◽  
Author(s):  
Tea-Yeon Hwang ◽  
Guk-Hwan An ◽  
Jeong-Ho Cho ◽  
Jongryoul Kim ◽  
Yong-Ho Choa
Keyword(s):  
Particle Size ◽  
Saturation Magnetization ◽  
Spray Pyrolysis ◽  
Intermediate Phase ◽  
Ultrasonic Spray Pyrolysis ◽  
Strontium Ferrite ◽  
Factors Affecting ◽  
Detailed Mechanism ◽  
Calcination Temperatures ◽  
Ultrasonic Spray

Strontium ferrite (hexaferrite), SrFe12O19, was successfully fabricated in sizes ranging from hundreds of nanometers to several micrometers by salt-assisted ultrasonic spray pyrolysis-calcination using different salt media. All samples were single phases of SrFe12O19 without the intermediate phase, α-Fe2O3, and their morphology was hexagonal. As calcination temperature increased, the size of as-calcined samples and saturation magnetization, Ms, increased while coercivity decreased. The particle size of the obtained nanoparticles varied depending on the salt media and calcination temperatures. The best magnetic properties obtained in this experiment were a coercivity of 6973 Oe with a saturation magnetization of 68.3 emu/g. To the best of our knowledge, these coercivity values are the highest ever obtained. We propose a detailed mechanism explaining the growth of these particles and conclude that the resulting single-domain particle size is about 70 nm, taking into account of factors affecting coercivity in ferrite nano- to micro-sized particles.

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