Method For Synthesis Of Nanoparticles Research Articles

Continuous synthesis of drug particles via spray drying of emulsions obtained by mechanical emulsification and ouzo effect

In the pharmaceutical field, nanoparticle formulation is an effective approach to improve the solubility of poorly water-soluble drugs. Spray drying is used for the synthesis of fine drug particles. The particle size obtained by spray drying generally depends on the size of the sprayed droplet. In this study, an emulsion spray drying method is proposed as a novel method for nanoparticle synthesis. Oil-in-water (O/W) nanoemulsions containing oil-soluble drugs were prepared. Spraying O/W emulsions could produce fine particles with the size of 122 nm. The particles obtained by emulsion spray drying were smaller than those obtained by spray drying without an emulsion. Furthermore, an Ouzo emulsion, which is a self-emulsification method, was investigated to improve the particle yield. The particles obtained by spray drying of the Ouzo emulsion had the size of 0.50 μm, which was smaller than those obtained without the Ouzo emulsion. Moreover, in-vitro dissolution tests were performed to evaluate the solubility of the obtained particles as well as the unprocessed drug powder. The particles obtained via spray drying of the Ouzo emulsions showed the highest dissolution rate. In summary, spray drying of O/W and Ouzo emulsions resulted in the production of fine drug particles.

Myco-generated and analysis of magnetite (Fe3O4) nanoparticles using Aspergillus elegans extract: A comparative evaluation with a traditional chemical approach

In the past few years, nanotechnology has emerged as one of the most interesting and cutting-edge research areas across all disciplines. Nanotechnology allows progress in all science fields to make novel materials and industry-different devices. Generally, nanoparticle synthesis methods are chemical, physical, and biological. The chemical and physical techniques use potentially harmful compounds, and the expense of these processes renders them unsuitable for nanoparticle synthesis. In light of this, it needs development strategies that are sustainable, economical, and eco-friendly viable. Through, biosynthesis, nanoparticles can overcome these disadvantages. One of the biological strategies is the myco-synthesis method, which connects the fields of mycology and nanotechnology. In this study, magnetite (Fe3O4) NPs have been synthesized using a myco-synthesis method by selecting Aspergillus elegans as a fungal species. Two extracts were used, growth medium and an aqueous extract. A comparative analysis between nanoparticles synthesized through myco-synthesis and those produced using conventional chemical methods has been conducted to substantiate the significance of the biological approach. The results of this study unequivocally establish that myco-synthesized nanoparticles exhibit superior and enhanced characteristics compared to those synthesized through chemical means, as ascertained through a comprehensive array of characterization techniques employed throughout the investigation. This contrast is observable in terms of the aggregation state, the existence of capping and stabilizing agents enveloping the nanoparticles, their magnetic and thermal attributes, and the enduring stability of these nanoparticles. These results highlight the significant promise of employing phytochemicals extracted from Aspergillus elegans as a highly suitable option for the biofabrication of Fe3O4 nanoparticles.

Mechanisms of formation and shape control of pentagonal Pd-nanostars and their unique properties in electrocatalytic methanol oxidation and membrane separation of high-purity hydrogen

Membranes on palladium alloy basis with surface modified by nanoparticles with high catalytic activity are useful in deep hydrogen purification and single-stage process of high-purity hydrogen production. This paper reports the development and improvement of methods for synthesis of Pd-based pentatwinned nanoparticles of strictly specified morphology with certain shapes, facets and composition. The competing effect of surfactants and optimization of the halide ions ratio in solution make it possible to direct a particle growth towards formation of pentatwinned Pd-nanostars. Pd–23%Ag coatings synthesized on the surface showed uniquely high peak current density of up to 238 mA cm−2 in alkaline methanol oxidation reaction. This is due to both increased surface area and greater catalytic activity of nanostars’ facets. A record increase in hydrogen permeability of up to 12.5 mmol s−1 m−2 at 100 °C has been achieved for palladium-silver membranes with modified surface. This indicates an acceleration of sorption/desorption stages. The developed method for controlling morphology of nanoscale coatings opens the way to the production of membrane hydrogen filters, which operate at room temperature.

Fabrication of Polypyrrole Hollow Nanospheres by Hard-Template Method for Supercapacitor Electrode Material.

Conducting polymers like polypyrrole, polyaniline, and polythiophene with nanostructures offers several advantages, such as high conductivity, a conjugated structure, and a large surface area, making them highly desirable for energy storage applications. However, the direct synthesis of conducting polymers with nanostructures poses a challenge. In this study, we employed a hard template method to fabricate polystyrene@polypyrrole (PS@PPy) core-shell nanoparticles. It is important to note that PS itself is a nonconductive material that hinders electron and ion transport, compromising the desired electrochemical properties. To overcome this limitation, the PS cores were removed using organic solvents to create hollow PPy nanospheres. We investigated six different organic solvents (cyclohexane, toluene, tetrahydrofuran, chloroform, acetone, and N,N-dimethylformamide (DMF)) for etching the PS cores. The resulting hollow PPy nanospheres showed various nanostructures, including intact, hollow, buckling, and collapsed structures, depending on the thickness of the PPy shell and the organic solvent used. PPy nanospheres synthesized with DMF demonstrated superior electrochemical properties compared to those prepared with other solvents, attributed to their highly effective PS removal efficiency, increased specific surface area, and improved charge transport efficiency. The specific capacitances of PPy nanospheres treated with DMF were as high as 350 F/g at 1 A/g. And the corresponding symmetric supercapacitor demonstrated a maximum energy density of 40 Wh/kg at a power density of 490 W/kg. These findings provide new insights into the synthesis method and energy storage mechanisms of PPy nanoparticles.

Green and chemical syntheses of silver nanoparticles: Comparative and comprehensive study on characterization, therapeutic potential, and cytotoxicity

The emergence of metallic nanoparticles through green synthesis has garnered significant recognition, shaping global research efforts towards eco-friendly practices, often termed as the green revolution. Specifically, the green synthesis of silver nanoparticles (AgNPs) has made considerable strides in the past decade, becoming a prominent fixture in the realm of science and technology. The study explores the synthesis and characterization of silver nanoparticles (AgNPs) using Cassia fistula L. flowers extract through chemical co-precipitation (CM_AgNPs) and green methods (CFF_AgNPs). Characterization techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), attenuated total reflectance fourier-transform infrared (FTIR), and X-ray diffraction (XRD), revealed irregular morphologies with agglomeration, polycrystalline nature, and intrinsic functional groups involved in capping AgNPs. Antioxidant assessment demonstrated superior antioxidative activity (84.48 %) in green-synthesized nanoparticles compared to chemically synthesized ones (75.87 %), and they exhibited dose-dependent anti-inflammatory effects with IC50 values CFF_AgNPs_30.19 μg/mL and CM_AgNPs _34.14 μg/mL respectively. The lower IC50 value of CFF_AgNPs_30.19 μg/mL signifies finer and better activity due to the presence of phytochemicals present in it. Whereas for CM_AgNPs the IC50 value is a 34.14 μg/mL which is solely due to AgNPs. To ensure the promising therapeutic aspects of AgNPs with a careful assessment of their safety profile, cytotoxicity of AgNPs on HEP3B cancer cells was evaluated through MTT assay, lactate dehydrogenase (LDH) release, and reactive oxygen species (ROS) level measurement. In the in vitro cytotoxicity evaluation, HEP3B demonstrated more pronounced dose-dependent adverse effects upon exposure to CFF_AgNPs compared to CM_AgNPs. This study underscores the bioactive potential of Cassia fistula L. mediated AgNPs, suggesting promising applications in biomedicine with environmental sustainability. The findings contribute to the growing interest in green synthesis methods for metallic nanoparticles and their potential benefits in various fields.

Unraveling the Mechanism of the Brust-Schiffrin Formation of Au25(SR)18 through Mass Spectrometry.

The Brust-Schiffrin (BS) method for gold nanoparticle (Au NP) synthesis is celebrated for its ability to produce highly monodisperse NPs from toluene-water solutions, in contrast to aqueous methods, such as the Turkevich method. Despite the method's success, the actual formation mechanisms remain largely unknown due to difficulty in studying the intermediates with species-differentiating techniques such as mass spectrometry (MS) or nuclear magnetic resonance (NMR). The issue lies in the use of solvents poorly compatible with these techniques and the difficulty in differentiating useful intermediate species from side products and impurities in such one-pot reactions. Herein, we use our recently formulated fully aqueous BS reaction to study the formation mechanisms. MS is chiefly employed to capture the intermediate species, and the Au25(SR)18 nanocluster is used as a thermodynamically reliable end-point. We find that the BS method may comprise a unilateral complex-shedding stage in addition to the known thiol-etching stage.

Enhanced butanone chemoresistive sensor utilizing cobalt oxide nanoparticles

Detection of volatile organic compounds (VOCs), particularly 2-butanone, has become crucial due to their widespread use and associated risks to human health. In this study, we present a novel synthesis method for spinel Co3O4 nanoparticles (NPs) employing a microwave-assisted hydrothermal approach followed by calcination and investigate their efficiency in VOC sensing applications. The Co3O4 NPs exhibit remarkable sensitivity and selectivity towards butanone at relatively low operating temperatures. VOC-sensing experiments reveal an optimal operating temperature of 250 °C, showcasing an advantage over existing sensors. Notably, the sensor exhibits high selectivity for butanone, with signal values 1.6–4.5 times higher than those for other VOCs, including acetaldehyde, ethanol, isopropanol, methanol, acetone, m-xylene, toluene, and benzene. Additionally, the Co3O4 NPs-based sensor demonstrates high sensitivity, detecting concentrations as low as 5 ppm of butanone, with fast response/recovery times of 41/86 s for 200 ppm of butanone and robust long-term stability. These findings underscore the potential of Co3O4 NPs as promising candidates for low-temperature butanone detection, which is essential for environmental and human health monitoring purposes.

Green synthesis and characterization of Ag nanoparticles using fresh and dry Portulaca Oleracea leaf extracts: Enhancing light reflectivity properties of ITO glass

AbstractSilver (Ag) nanoparticles (NPs) are perceiving remarkable progress during the past few periods due to its exclusive properties in many applications. Recently, green synthesis method of NPs is racing against traditional chemical and physical methods by avoiding the use of many toxic chemicals, and expensive devices. Accordingly, in this study, dry and fresh Portulaca‐oleracea L. leaf extract has been employed for producing AgNPs as a reducing, capping and stabilizing agents. This process is simple, eco‐friendly and green. UV–vis spectra showed the formation of AgNPs represented by the change of a colorless liquid to brownish solution. The crystallinity of the AgNPs, was confirmed by X‐ray diffraction (XRD). The contribution of the available functional groups of the leaf extract in the reduction and capping process of NPs was demonstrated using Fourier transform infrared spectroscopy (FTIR). This study showed that fresh Portulaca‐oleracea L. leaf extract provides better NPs in terms of stability, purity, degree of crystallinity and spherical shape. The biosynthesized AgNPs from both procedures were coated on the indium tin oxide (ITO) glass substrates to enhance the reflectivity property. It has been shown that the utilized AgNPs, from fresh Portulaca‐oleracea L. extract, has smaller size and negligeable agglomeration, consequently lower light transmittance.

Moringa oleifera Seed Cake: A Review on the Current Status of Green Nanoparticle Synthesis

Growing demands for sustainable and ecological nanoparticle synthesis methods have incentivized the scientific community to develop new approaches to counteract these challenges. Green synthesis resorts to biocomponents obtained from plants, bacteria, fungi, and other organisms to synthesize nanostructures, with beneficial gains in the economic and ecological cost associated with the process, simplicity of the process, and resource efficiency. Moringa oleifera, a native plant originally from India with immense nutritive value, has long been used by researchers in the biosynthesis of nanoparticles. Leaves, flowers, bark, and seeds are among the “miracle tree” parts that can be used in nanoparticle green synthesis. Moringa oleifera seed cake, a by-product obtained from defatted seeds, is often overlooked due to its apparent low commercial value. The main objective of this review is to highlight the recent findings reported in the literature on nanoparticles/nanocomposites synthesized with seed cake biocompounds acting as reducing/capping agents. Furthermore, we analyzed the methods currently employed for the extraction of bioactive compounds. Moringa oleifera seed for industrial applications was also addressed.

Green synthesis of Superparamagnetic Iron Oxide and Silver Nanoparticles in Satureja hortensis Leave Extract: Evaluation of Antifungal Effects on Botryosphaeriaceae Species.

In recent years, green synthesis methods of metallic nanoparticles (MNPs) have been attractive because of the more facile, cheaper, and appropriate features associated with biomolecules in MNPs biosynthesis. This research represented an easy, fast, and environmentally friendly method to biosynthesis of superparamagnetic iron oxide nanoparticles (SPIONPs) and silver nanoparticles (AgNPs) by the Satureja hortensis leaf extract as stabilizer and reducer. The SPIONPs synthesized in co-precipitation method. The biosynthesized SPIONPs and AgNPs were studied their antifungal effects against three Botryosphaeriaceae plant pathogens, Botryosphaeria dothidea, Diplodia seriata, and Neofusicoccum parvum. UV-visible spectra (UV-Vis), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), field emission scanning electron microscopy (Fe-SEM), energy-dispersive X-ray spectroscopy (EDX), and vibrating-sample magnetometer (VSM) analyses were used to evaluate the physicochemical properties and verify the formation of green synthesized SPIONPs and AgNPs. UV-Vis spectra revealed absorption peaks at 243 and 448 nm for SPIONs and 436 nm for AgNPs, respectively. Microscopic and XRD analysis showed that SPIONPs and AgNPs was found spherical in shape with an average particle size of SPIONPs and AgNPs 10 and 12 nm, respectively. The antifungal test against Botryosphaeriaceae species showed that SPIONPs and AgNPs possessantifungal properties against B. dothidea, D. seriata, and N. parvum. However, AgNPs exhibits greaterantifungal activity than SPIONPs. Theresultsof thecytotoxicitytests of SPIONs and AgNPs on the MCF-7 cell line showed that AgNPs was significantly more cytotoxictowardsthe MCF-7 cell line, whereas nosignificant cytotoxiceffect was recorded by SPIONs. Therefore, these biosynthesized MNPs could be substituted for toxic fungicides that are extensively applied in agriculture and contribute to environmental health and food safety.

A novel approach for the green synthesis of iron nanoparticles using marigold extract, black liquor, and nanocellulose: Effect on marigold growth parameters

This study aimed to investigate a novel method for the green synthesis of iron nanoparticles (FeNPs) using marigold extract (Calendula officinalis L), kraft pulping black liquor, and nanocellulose. Then, the efficacy of FeNPs as a direct nanofertilizer on the growth parameters of marigold was investigated. Characterization techniques including FESEM, EDX, VSM, and FTIR were used to confirm the successful synthesis of FeNPs. The characterization results confirmed the formation and presence of FeNPs in the 20–100 nm range. FeNPs synthesized with nanocellulose notably enhanced marigold growth parameters compared to other materials. However, all nanoparticle variants, including those from marigold extract and black liquor, improved germination, plant height, root length, and plant dry weight compared to the control. Moreover, treatments exhibited higher available iron and total plant iron levels than the control. Thus, employing 10 mg FeNPs (prepared with 5.0 % nanocellulose) appears optimal for enhancing marigold growth and yield.

A novel sonoelectrochemical approach for preparing of ZnO nanoparticles

A novel, rapid, and facile method for one-step sonoelectrochemical synthesis of zinc oxide nanoparticles (UEZ) was introduced in this study. The optimum operating parameters have been selected at a voltage of 7.5 V, KCl concentration of 0.5 M, and the reaction time of 60 min. The as-prepared UEZ were characterized by XRD, SEM, and HRTEM. It was found that the UEZ has a hexagonal wurtzite structure with high crystalline quality, good purity, a size range of 30–100 nm, and good photocatalytic degradation of methylene blue. This work provides a facile route for large-scale synthesizing ZnO nanoparticles via anodization.

Effect of Micromixer Design on Lipid Nanocarriers Manufacturing for the Delivery of Proteins and Nucleic Acids.

Lipid-based nanocarriers have emerged as helpful tools to deliver sensible biomolecules such as proteins and oligonucleotides. To have a fast and robust microfluidic-based nanoparticle synthesis method, the setup of versatile equipment should allow for the rapid transfer to scale cost-effectively while ensuring tunable, precise and reproducible nanoparticle attributes. The present work aims to assess the effect of different micromixer geometries on the manufacturing of lipid nanocarriers taking into account the influence on the mixing efficiency by changing the fluid-fluid interface and indeed the mass transfer. Since the geometry of the adopted micromixer varies from those already published, a Design of Experiment (DoE) was necessary to identify the operating (total flow, flow rate ratio) and formulation (lipid concentration, lipid molar ratios) parameters affecting the nanocarrier quality. The suitable application of the platform was investigated by producing neutral, stealth and cationic liposomes, using DaunoXome®, Myocet®, Onivyde® and Onpattro® as the benchmark. The effect of condensing lipid (DOTAP, 3-10-20 mol%), coating lipids (DSPE-PEG550 and DSPE-PEG2000), as well as structural lipids (DSPC, eggPC) was pointed out. A very satisfactory encapsulation efficiency, always higher than 70%, was successfully obtained for model biomolecules (myoglobin, short and long nucleic acids).

UV-assisted green synthesis of silver nanoparticles and their characterizations

Silver nanoparticles are receiving discernible attention because of their potential applications in different fields of science and technology. However, chemical synthesis methods leave behind harmful byproducts. Here, we report an alternative method for the rapid synthesis of silver nanoparticles through radiation-assisted green synthesis. Aqueous leaf extract of Ocimum sanctum is used as a reducing and stabilizing agent with silver nitrate solution under UV-B irradiation. UV-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDX), photoluminescence spectroscopy (PL) and fourier transform infrared spectroscopy (FTIR) collectively revealed that bio reduced silver nanoparticles were polydisperse, polycrystalline, spherical in shape, had an average diameter of 40.1 nm, and were stable more than six months. These observations suggest that radiation-assisted green synthesis is a quick and eco-friendly method for the large-scale production of stable silver nanoparticles without any harmful byproducts.

Eco-Friendly Synthesis Methods of Gold Nanoparticles, Their Characterization and Applications in Diagnostic, Therapeutic and Sensors

Nanoparticles have unique traits which make them useful for different purposes. Numerous methods are used to manufacture nanoparticles at commercial scale. Gold nanoparticles (AuNPs) are one of the most utilized and preferred nanoparticles due to their traits like low resistivity, less toxicity, optical, high stability, fluorescence quenching ability, and "surface plasmon resonance". Gold nanoparticles were utilized in ancient Roman Times for staining glasses and till now their new applications are being discovered every day. Various methodologies are utilized for Gold nanoparticle synthesis including conventional chemical methods, UV rays, polymers, ultrasound, plant and microbe-mediated techniques, etc. Conventional techniques are not eco-friendly or cost-effective. Nowadays plants and microbes being cost-effective and eco-friendly are preferred for gold nanoparticle synthesis. Various extracellular, intracellular, and biomolecular techniques are being utilized to manufacture gold nanoparticles. Gold nanoparticles have a vast scope in chemical, biomedicine, food, electronic and forensic industries. AuNPs are widely utilized as sensors, also as carriers in Drug delivery, Photothermal therapy, Heavy metal ion detection etc. This review describes various synthesis techniques, applications, and characterizations of AuNPs.

Multifaceted chemical and bioactive features of Ag@TiO2 and Ag@SeO2 core/shell nanoparticles biosynthesized using Beta vulgaris L. extract

Due to increasing concerns about environmental impact and toxicity, developing green and sustainable methods for nanoparticle synthesis is attracting significant interest. This work reports the successful green synthesis of silver (Ag), silver-titanium dioxide (Ag@TiO2), and silver-selenium dioxide (Ag@SeO2) nanoparticles (NPs) using Beta vulgaris L. extract. Characterization by XRD, SEM, TEM, and EDX confirmed the successful formation of uniformly distributed spherical NPs with controlled size (25 ± 4.9 nm) and desired elemental composition. All synthesized NPs and the B. vulgaris extract exhibited potent free radical scavenging activity, indicating significant antioxidant potential. However, Ag@SeO2 displayed lower hemocompatibility compared to other NPs, while Ag@SeO2 and the extract demonstrated reduced inflammation in a carrageenan-induced paw edema animal model. Interestingly, Ag@TiO2 and Ag@SeO2 exhibited strong antifungal activity against Rhizoctonia solani and Sclerotia sclerotium, as evidenced by TEM and FTIR analyses. Generally, the findings suggest that B. vulgaris-derived NPs possess diverse biological activities with potential applications in various fields such as medicine and agriculture. Ag@TiO2 and Ag@SeO2, in particular, warrant further investigation for their potential as novel bioactive agents.

Biosynthesis of Cu-In-S Nanoparticles by a Yeast Isolated from Union Glacier, Antarctica: A Platform for Enhanced Quantum Dot-Sensitized Solar Cells.

In recent years, the utilization of extremophile microorganisms for the synthesis of metal nanoparticles, featuring enhanced properties and diverse compositions, has emerged as a sustainable strategy to generate high-quality nanomaterials with unique characteristics. Our study focuses on the biosynthesis of Cu-In-S (CIS) nanoparticles, which has garnered considerable attention in the past decade due to their low toxicity and versatile applications in biomedicine and solar cells. Despite this interest, there is a notable absence of reports on biological methods for CIS nanoparticle synthesis. In this research, three yeast species were isolated from soil samples in an extreme Antarctic environment-Union Glacier, Ellsworth Mountains. Among these isolates, Filobasidium stepposum demonstrated the capability to biosynthesize CIS nanoparticles when exposed to copper sulfate, indium chloride, glutathione, and cysteine. Subsequent purification and spectroscopic characterization confirmed the presence of characteristic absorbance and fluorescence peaks for CIS nanoparticles at 500 and 650 nm, respectively. Transmission electron microscopy analysis revealed the synthesis of monodisperse nanoparticles with a size range of 3-5 nm. Energy dispersive X-ray spectroscopy confirmed the composition of the nanoparticles, revealing the presence of copper, indium, and sulfur. The copper/indium ratio ranged from 0.15 to 0.27, depending on the reaction time. The biosynthesized CIS nanoparticles showed higher photostability than biomimetic nanoparticles and demonstrated successful application as photosensitizers in quantum dot-sensitized solar cells (QDSSC), achieving a conversion efficiency of up to 0.0247%. In summary, this work presents a cost-effective, straightforward, and environmentally friendly method for CIS nanoparticle synthesis. Furthermore, it constitutes the first documented instance of a biological procedure for producing these nanoparticles, opening avenues for the development of environmentally sustainable solar cells.

Green Synthesis of ZnO Nanoparticles Using Potato Extracts (Solanum tuberosum) As an Antibacterial Agent in the Active Packaging For Food Products

In this work, we have implemented an eco-friendly method for synthesis of zinc oxide nanoparticles (ZnO NPs) using potato extracts (Solanum tuberosum) as the natural bio-reductants and stabilizing agent. Meanwhile the zinc nitrate octahydrate (Zn[NO3] 2.6H2O) and ammonium hydroxide (NH4OH) were used as the precursor of ZnO NPs. The sediment of Zn(OH)2 was separated from the solvent using centrifuge, and further calcinated at the temperature of 500ºC so that formed ZnO nanoparticles. SEM micrograph of ZnO NPs shows the hexagonal shapes with particles size around 50–100 nm. The XRD spectra confirms that ZnO NPs exhibited well crystalline nature, however, there were impurity peaks caused by the potato extracts addition. From the FTIR analysis, we obtained the existence of another chemical compounds, denoting the presence of stabilizing and reducing agent from potato extract.
 Keywords: ZnO nanoparticles, green synthesis, antibacterial and active packaging

A Facile Method for Synthesis of α-Fe2O3 Nanoparticles and Assessment of Their Characterization

Recently, magnetic nanomaterials have gained much attention from researchers because of their various unique physical and chemical properties and usage in a wide range of technological aspects. In this study, the synthesis of α-Fe2O3 nanoparticles was performed by a simple co-precipitation method. The synthesis of α-Fe2O3 nanoparticles was carried out by mixing ferric nitrate and oxalic acid in an aqueous solution followed by evaporation, resulting in the solution’s dried form. The synthesized nanoparticles were analyzed by XRD, FTIR, Raman spectra, SEM-EDX, DSC, BET, and Zeta potential for detailed examination of the morphology, structure, and other physicochemical characteristics. The XRD results confirmed that the nanoparticles formed were Hematite (α-Fe2O3) after the evaluation of obtained spectra compared to the Joint Committee on Powder Diffraction Standards Database (JCPDS). The FTIR spectra showed various bonds among functional groups, O-H bending, Fe-O group, and within-vibration bonds. The phase study of the α-Fe2O3 nanoparticles was performed by using Raman spectroscopy. SEM depicted a sphere-like or rhombohedral (hexagonal) structure, and the EDX spectrum confirmed the peaks of iron and oxygen.

Determination of droplet size from wide-angle light scattering image data using convolutional neural networks

Wide-angle light scattering (WALS) offers the possibility of a highly temporally and spatially resolved measurement of droplets in spray-based methods for nanoparticle synthesis. The size of these droplets is a critical variable affecting the final properties of synthesized materials such as hetero-aggregates. However, conventional methods for determining droplet sizes from WALS image data are labor-intensive and may introduce biases, particularly when applied to complex systems like spray flame synthesis. To address these challenges, we introduce a fully automatic machine learning-based approach that employs convolutional neural networks (CNNs) in order to streamline the droplet sizing process. This CNN-based methodology offers further advantages: it requires few manual labels and can utilize transfer learning, making it a promising alternative to conventional methods, specifically with respect to efficiency. To evaluate the performance of our machine learning models, we consider WALS data from an ethanol spray flame process at various heights above burner surface, where the models are trained and cross-validated on a large dataset comprising nearly 35000 WALS images.