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

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

Industrial & Engineering Chemistry Research ◽

10.1021/ie070821d ◽

2008 ◽

Vol 47 (5) ◽

pp. 1650-1659 ◽

Cited By ~ 101

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

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

Materials ◽

10.3390/ma13010038 ◽

2019 ◽

Vol 13 (1) ◽

pp. 38 ◽

Cited By ~ 3

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.

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SYNTHESIS OF CALCIUM-PHOSPHATE MICROSPHERE WITH WELL-CONTROLLED PARTICLE SIZE BY ULTRASONIC SPRAY-PYROLYSIS TECHNIQUE AND THEIR SINTERABILITY

Phosphorus Research Bulletin ◽

10.3363/prb1992.19.0_1 ◽

2005 ◽

Vol 19 (0) ◽

pp. 1-6

Author(s):

MAMORU AIZAWA ◽

ATSUSHI ONO ◽

TOSHIKI OHNO ◽

PAK-KON CHOI

Keyword(s):

Particle Size ◽

Calcium Phosphate ◽

Spray Pyrolysis ◽

Spray Pyrolysis Technique ◽

Ultrasonic Spray Pyrolysis ◽

Ultrasonic Spray Pyrolysis Technique ◽

Ultrasonic Spray

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

Korean Journal of Metals and Materials ◽

10.3365/kjmm.2021.59.5.289 ◽

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.

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Ultrasonic Spray Pyrolysis Deposition of SDS Surfactant Assisted Copper Oxide Thin Films

i-manager’s Journal on Future Engineering and Technology ◽

10.26634/jfet.9.4.2744 ◽

2014 ◽

Vol 9 (4) ◽

pp. 17-23

Author(s):

Iqbal Singh ◽

◽

Taminder Singh ◽

Keyword(s):

Thin Films ◽

Copper Oxide ◽

Spray Pyrolysis ◽

Ultrasonic Spray Pyrolysis ◽

Oxide Thin Films ◽

Ultrasonic Spray ◽

Spray Pyrolysis Deposition ◽

Sds Surfactant ◽

Surfactant Assisted

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Fireworks: How to Simulate the Manufacture and Operation in the Atmosphere with the Substitution of Ultrasonic Spray Pyrolysis

Current Nanoscience ◽

10.2174/1573413714666180726143918 ◽

2018 ◽

Vol 15 (2) ◽

pp. 147-156

Author(s):

Rebeka Rudolf ◽

Urban Ferčec ◽

Mohammed Shariq

Keyword(s):

Spray Pyrolysis ◽

Final Section ◽

Web Of Science ◽

Raw Materials ◽

Ultrasonic Spray Pyrolysis ◽

Physiochemical Properties ◽

Physical Size ◽

Respiratory Problems ◽

Ultrasonic Spray ◽

Temperature Ranges

Background: This review provides a closer look at recent work in the field of fireworks manufacture, which could see the replacement of micron-sized particles with their nano-scaled counterparts. Moreover, we also discuss micron-sized particles as well as nanoparticles (NPs) from K, Fe, Al, Ti, Ba, etc., that are produced in the atmosphere as a result of these fireworks. One of the possible technological substitutes for fireworks is presented in detail, i.e., the use of ultrasonic spray pyrolysis (USP) technology. Method: We searched Google, Web of Science and PubMed for a literature survey of fireworks and their products: firecrackers, micron-sized and nanoparticles. Moreover, we used some of our own knowledge and experimental data to strengthen the possibility of simulating the synthesis of firework products on the laboratory scale. Results: The use of nano reactants and oxidisers has seen a substantial increase in the sound efficiency and a decrease in the amount of chemicals used, making fireworks more eco-friendly. The application of Al- and Ti-based nano flash powder in the size range from 35 nm to 50 μm resulted in a significant improvement in the ignition properties of the fireworks. Under changing aerodynamic conditions, it is difficult to collect them as samples for real-time monitoring, needed for their characterization or the testing of their harmfulness under laboratory conditions. As a result, NPs below 100 nm in the surroundings could be easily inhaled into the lungs and cause more pulmonary and respiratory problems than micron-sized particles. USP produces nanoparticles in the laboratory that could replace the conventional micron-sized firecracker raw materials, or nanoparticles that are similar to those formed by fireworks. It will also help to identify the physiochemical properties of the airborne particulates in order to understand and evaluate their impact. </P><P> This review could be valuable for a controlled economic synthesis through USP, and in the use of nanopowders in pyrotechnology that could reduce pollution to a great extent, thus contributing to the growth and good practise of the fireworks industry. With respect to the USP synthesis, we have also discussed in detail the physical (size, shape) and chemical (composition) characteristics of Al2O3 and TiO2 NPs from different precursors and their temperature ranges. An in-depth explanation for a comparative analysis for the formation mechanism of nanoparticles through both fireworks and USP is presented in the final section. We can produce nanoparticles in the laboratory with ultrasonic spray pyrolysis that have similar properties to those produced from fireworks and can then be used for further testing.

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Ultrasonic spray pyrolysis deposited CTS thin film: Variation of thiourea concentration in the film

Materials Today Proceedings ◽

10.1016/j.matpr.2021.04.513 ◽

2021 ◽

Author(s):

Sabina Rahaman ◽

M. Anantha Sunil ◽

Monoj Kumar Singha ◽

Kaustab Ghosh

Keyword(s):

Thin Film ◽

Spray Pyrolysis ◽

Ultrasonic Spray Pyrolysis ◽

Ultrasonic Spray ◽

Thiourea Concentration

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Strong texture tuning along different crystalline directions in glass-supported CeO2 thin films by ultrasonic spray pyrolysis

Scientific Reports ◽

10.1038/s41598-021-81353-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Inti Zumeta-Dubé ◽

José Manuel García Rangel ◽

Jorge Roque ◽

Issis Claudette Romero-Ibarra ◽

Mario Fidel García Sánchez

Keyword(s):

Thin Films ◽

Spray Pyrolysis ◽

Spray Pyrolysis Technique ◽

Morphological Characteristics ◽

Ultrasonic Spray Pyrolysis ◽

Cost Effective ◽

Growth Direction ◽

Large Area ◽

Smart Windows ◽

Ultrasonic Spray

AbstractThe strong facet-dependent performance of glass-supported CeO2 thin films in different applications (catalysis, smart windows, etc.) has been the target of diverse fundamental and technological approaches. However, the design of accurate, cost-effective and scalable methods with the potential for large-area coverage that produce highly textured glass-supported CeO2 thin films remains a technological challenge. In the present work, it is demonstrated that under proper tuning conditions, the ultrasonic spray pyrolysis technique enables one to obtain glass-supported polycrystalline CeO2 films with noticeable texture along both the (100) and (111) directions, as well as with randomly oriented crystallites (no texture). The influence of flow rates, solution molarity, and substrate temperature on the texture and morphological characteristics, as well as optical absorption and Raman response of the deposited films, is evaluated. The obtained results are discussed on the basis of the combined dependence of the CeO2-exposed surfaces on the thermodynamic stability of the corresponding facets and the reaction kinetics, which modulate the crystallite growth direction.

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