Article
Energy & Fuels
Yihua Ren, Jinzhi Cai, Heinz Pitsch
Summary: Flame spray pyrolysis is a promising technology for synthesizing metal-oxide nanomaterials, but numerical simulation faces challenges. A single-droplet model has been developed to describe multicomponent droplet combustion and guide precursor and process design.
Article
Engineering, Chemical
R. Tischendorf, M. Simmler, C. Weinberger, M. Bieber, M. Reddemann, F. Froede, J. Lindner, H. Pitsch, R. Kneer, M. Tiemann, H. Nirschl, H-J Schmid
Summary: This study investigates the flame spray pyrolysis setup and particle extraction methods, examining the impact of different precursor formulations on particle formation pathways. Results show that an acidic precursor solution leads to gas-to-particle conversion, while the absence of acid results in a droplet-to-particle pathway. Customized extraction techniques enable in situ research on particle structure evolution.
JOURNAL OF AEROSOL SCIENCE
(2021)
Article
Chemistry, Physical
Malte Schalk, Suman Pokhrel, Marco Schowalter, Andreas Rosenauer, Lutz Maedler
Summary: The thickness of functional layers has significant implications on the performance in various technologies. The study demonstrated the deposition of different thicknesses of functional layers and showed that adjusting layer thickness and primary particle size can benefit applications depending on porosity, such as catalysis or gas sensing. The relationship between surface and volume of the layers is crucial for high performance evaluations.
Article
Materials Science, Ceramics
Erdem Tevfik Ozdemir, Serdar Yildirim, Berk Ozler, Tuncay Dikici, Mustafa Erol, Metin Yurddaskal
Summary: Manganese ferrite nanoparticles were synthesized using flame spray pyrolysis, and the effects of annealing on the properties of the nanoparticles were investigated. XRD analysis confirmed the spinel ferrite structure of the synthesized nanoparticles. The nanoparticles exhibited hemispherical-cubic shape with an average size below 100 nm. XPS analysis revealed the chemical bond structures of the nanoparticles. The saturation magnetization decreased with increasing annealing temperature, while coercivity increased.
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Martin T. Matter, Leonida Maliqi, Kerda Keevend, Stefanie Guimond, Judith Ng, Efe Armagan, Markus Rottmar, Inge K. Herrmann
Summary: Dental implant failure is a prevalent issue globally, with current surface modifications facing challenges in achieving sufficient integration and preventing biofilm formation. Introduction of nanostructures on the surface shows promise in improving implant-tissue contact, but existing coating processes are limited in versatility and cost. A highly modular single-step method has been developed to produce multicomponent porous bioactive nano-structured coatings on implants, with potential applications in dental implantology and beyond.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Thermodynamics
M. F. B. Stodt, Jan Derk Groeneveld, Lutz Maedler, Johannes Kiefer, Udo Fritsching
Summary: This study investigates the occurrence of in-flight droplet microexplosions (mu-explosions) during flame spray pyrolysis and confirms the findings through single drop experiments. It is found that there are distinct mu-explosions happening at high frequencies during the synthesis of iron oxide nanoparticles. This finding is significant for understanding the role and relevance of mu-explosions in the production and formulation of functional nanoparticles.
COMBUSTION AND FLAME
(2022)
Article
Materials Science, Multidisciplinary
Siti Aisyah Nurmaulia Entifar, Joo Won Han, Jung Ha Kim, Anky Fitrian Wibowo, Jihyun Park, Ajeng Prameswati, Sung Bin Park, Min-Seok Kim, Yong Hyun Kim
Summary: Nanoparticles, especially those produced through flame spray pyrolysis (FSP), have unique properties and great potential in various applications. In this study, tungsten trioxide (WO3) nanoparticles were successfully synthesized and carbon doping was found to improve their coverage and photodegradation performance as a photocatalyst.
Article
Engineering, Environmental
Shuo Liu, Mohammad Moein Mohammadi, Mark T. Swihart
Summary: This review provides an overview of flame aerosol synthesis of catalysts, including the mechanisms, applications, and recent progress. By controlling process parameters and reactor configuration, catalyst structures can be tailored. The advantages, limitations, and future research directions of flame-made catalysts are also discussed in the review.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Thermodynamics
Debolina Dasgupta, Pinaki Pal, Roberto Torelli, Sibendu Som, Noah Paulson, Joseph Libera, Marius Stan
Summary: FSP is a method for large-scale production of nanoparticles, where a CFD model has been developed to simulate key phenomena in the particle synthesis process. The study shows that particle size is strongly correlated with precursor concentration, pilot flow rate impacts flame dynamics, and dispersion gas flow rate influences flame shape for control of particle growth.
COMBUSTION AND FLAME
(2022)
Article
Engineering, Chemical
Malte Bierwirth, Vinzent Olszok, Varun Aiyar Ganesan, Jalal Poostforooshan, Alfred P. Weber
Summary: Electrospray of liquid precursor coupled to flame spray pyrolysis enables the synthesis of diverse metal oxide nanoparticles. By utilizing a movable burner and a static sampling system, particle size distributions across and along the flame can be characterized. It was found that high quality nanopowders can be produced from simple precursor solutions as long as the droplet size is sufficiently small, even in the early stages of particle formation.
CHEMIE INGENIEUR TECHNIK
(2021)
Article
Materials Science, Multidisciplinary
Srecko Stopic, Felix Wenz, Tatjana-Volkov Husovic, Bernd Friedrich
Summary: The synthesis of silica particles through ultrasonic spray pyrolysis at high temperature allows for controlled morphology and size, with experimental results matching theoretical calculations. Characterization using X-ray diffraction and scanning electron microscopy is common practice. Compared to other methods, ultrasonic spray offers the advantages of easy setup of individual process segments, one-step continuous synthesis, and the ability to synthesize nanoparticles from various precursors.
Article
Chemistry, Analytical
K. Khamfoo, A. Wisitsoraat, M. Punginsang, A. Tuantranont, C. Liewhiran
Summary: Nb-doped SnO2 nanoparticles were synthesized via flame spray pyrolysis for the first time, with 0.5 wt% Nb content providing the best sensor response to 1 vol% C2H2 at 350 degrees Celsius. The sensor also exhibited low humidity dependence, good long-term stability, and high C2H2 selectivity.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Chemistry, Analytical
K. Inyawilert, A. Sukee, M. Siriwalai, A. Wisitsoraat, J. Sukunta, A. Tuantranont, S. Phanichphant, C. Liewhiran
Summary: Erbium-doped SnO2 nanoparticles with different Er concentrations were synthesized and their gas-sensing properties were investigated. The sample with 0.1 wt% Er exhibited the best response to C2H4O, showing significantly improved performance compared to the undoped sample.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Thermodynamics
Fuchang Gao, Zuwei Xu, Haibo Zhao
Summary: In this study, flame spray pyrolysis (FSP) was used to synthesize Pt/TiO2 catalysts with surface-supported isolated Pt atoms, achieving single-atom Pt dispersion by controlling flame temperature and precursor/solvent formulation. The FSP-made catalysts showed high activity in a photocatalysis water splitting system, with isolated Pt atoms acting as the main active sites. The performance and cost efficiency of catalysts were greatly improved by engineering atomically dispersing Pt on the support surface.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Optics
Silvana De Iuliis, Roberto Donde, Igor Altman
Summary: This study analyzes the evolution of titania nanoparticles based on their light emission spectra, comparing laser-induced light emission with spontaneous emission in flame. Results show a peculiar temperature difference between irradiated and nonirradiated particles at different laser fluences, with anomalously high titania absorption at low fluence. The increase in Urbach energy is speculated to account for the change in optical properties, attributed to structural defects induced by synthesis conditions and/or laser irradiation.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2021)
Article
Engineering, Chemical
M. Ulrich Goebel, Juergen U. Keller, Karl Meller, Ingo Schmitz, Thomas Seeger, Eva Schieferstein
Summary: By measuring the adsorption and desorption behavior of activated carbon filters on fuel vapor mixtures over time, it was found that dry regeneration can enhance their long-term suitability. This study helps explain the increased filter failures due to bioethanol blends and moist regeneration fluid.
CHEMIE INGENIEUR TECHNIK
(2022)
Article
Thermodynamics
Florian J. Bauer, Phillipp A. B. Braeuer, Simon Assmann, Maximilian A. Thiele, Franz J. T. Huber, Stefan Will
Summary: This study uses a method to infer the optical band gap value and transition type exponent of soot to investigate its electronic nature and optical properties during the formation process. Experimental results reveal an increase in band gap energy and a decrease in the transition type exponent for young soot, while mature soot has an indirect band gap value close to 0.2 eV.
COMBUSTION AND FLAME
(2022)
Article
Optics
Markus Labus, Peter Lang, Leo Bahr, Franz J. T. Huber, Stefan Will
Summary: A calibration-free two-line atomic fluorescence setup was designed for optical high-precision temperature measurements in combustion processes, focusing on practical applicability. The setup includes a novel homogeneous and laminar hexagonal close-packed burner for future calibration purposes, allowing for high-precision temperature measurements and absolute measurements of the indium transitions in a combustion environment. Including the most abundant indium isotopes in the calculation model improved the quality of the hyperfine spectra fitting, resulting in minimized residuals and systematic errors compared to previous approaches.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2022)
Article
Chemistry, Analytical
Julian F. A. Perlitz, Lukas Gentner, Phillipp A. B. Braeuer, Stefan Will
Summary: This paper presents an in situ investigation method for studying the secondary structure changes during protein drying using time-resolved Raman spectroscopy in an acoustic levitator. The developed setup successfully quantifies the relative secondary structure changes for two model substances, showing an increase in beta-sheet structure and a decrease in alpha-helix and random coil structures during drying.
Article
Engineering, Chemical
Manfred Ulrich Goebel, Juergen U. Keller, Karl Meller, Ingo Schmitz, Thomas Seeger, Eva Schieferstein
Summary: This paper discusses the importance of fuel vapor retaining systems in gasoline vehicles and presents measurements of the regeneration processes using high humidity gas. It also highlights the limitations of current testing procedures and quality parameters in representing real operating conditions, and suggests the need for new standards.
Article
Chemistry, Physical
Joerg Lampe, Steffen Menz, Kander Akinci, Kai Boehm, Thomas Seeger, Thomas Fend
Summary: This paper investigates the operational strategy of a pilot plant for regenerative hydrogen production based on two-step thermochemical redox cycles, with a focus on optimizing operational parameters for the highest solar-to-fuel efficiency. Using a highly accurate simulation model and well-suited optimization routines, new insights into the most efficient operational strategies are revealed. The study considers the material and technical limits of the used components, yielding reliable practical results. Optimal operational parameters are found using a temperature swing strategy, resulting in a solar-to-fuel plant efficiency of up to 1.1%.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Polymer Science
Bjoern Duesenberg, Sebastian-Paul Kopp, Florentin Tischer, Stefan Schruefer, Stephan Roth, Jochen Schmidt, Michael Schmidt, Dirk W. Schubert, Wolfgang Peukert, Andreas Buck
Summary: This study investigates the use of charge control substances (CCS) as additives for polymer powders in powder-based additive manufacturing. Functionalization of commercially available polymer powder with CCS is shown to have an impact on powder charge and the potential of this method is demonstrated through analysis of various parameters.
Article
Optics
Ulrich Retzer, Hannah Ulrich, Stefan Will, Lars Zigan
Summary: In this study, tracer-based laser-induced fluorescence (LIF) technique was used to investigate temperature and fuel courses in a rapid compression machine under high temperature and pressure conditions. The results showed that there were inhomogeneities in the temperature and concentration fields during the compression process, which were caused by the heat transfer and piston movement.
APPLIED PHYSICS B-LASERS AND OPTICS
(2022)
Article
Chemistry, Physical
Jonas Bollmann, Nikolas Schmidt, Dominik Beck, Patrick Preuster, Lars Zigan, Peter Wasserscheid, Stefan Will
Summary: Liquid organic hydrogen carrier (LOHC) systems provide a safe and dense form of hydrogen storage and transportation at ambient conditions. This study utilizes the exhaust gas enthalpy of a porous media burner to supply heat for the dehydrogenation of LOHC compound, improving system dynamics and power density. The direct heating concept demonstrates potential for LOHC-based hydrogen provision systems, offering a dynamic hydrogen release and precise temperature control.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Optics
Markus Labus, Peter Lang, Franz J. T. Huber, Stefan Will
Summary: This Letter demonstrates, for the first time, the calibration-free imaging of particle-laden flames' full-frame temperature fields using two-line atomic fluorescence (TLAF) of indium. The technique utilizes the excitation and detection of specific transitions in indium atoms and shows promise for future applications in flame synthesis of nanoparticles containing indium compounds.
Article
Automation & Control Systems
Phillipp A. B. Braeuer, Leo A. Bahr, Hans-Juergen KoB, Stefan Will
Summary: Raman spectroscopy is a versatile tool for non-invasive determination of system or material properties. We propose a novel physics-based method for advanced spectral reconstruction (ASR) to weaken setup dependency. By explicitly incorporating experimental influences into the reconstruction model, we can achieve model transfer and share spectral quantification models among different sensors and/or researchers.
CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS
(2023)
Article
Chemistry, Physical
Jonas Bollmann, Kerstin Mitlaender, Dominik Beck, Patrick Schuehle, Florian Bauer, Lars Zigan, Peter Wasserscheid, Stefan Will
Summary: For a hydrogen-based economy, safe and efficient hydrogen storage is crucial. This study successfully utilized the exhaust gas enthalpy of a porous media burner to supply heat for the dehydrogenation of LOHC compound H18-DBT. The maximum hydrogen power achieved was 3.9 kWth, demonstrating the importance of dynamic hydrogen supply for applications with fluctuating hydrogen demand.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Analytical
Uwe Frank, Jana Dienstbier, Florentin Tischer, Simon E. E. Wawra, Lukas Gromotka, Johannes Walter, Frauke Liers, Wolfgang Peukert
Summary: The increasing complexity in particle science and technology requires the ability to deal with multidimensional property distributions. We present the theoretical background for multidimensional fractionations by transferring the concepts known from one dimensional to higher dimensional separations. Examples of technical realizations for shape-selective separation in a hydrocyclone and for density-selective separation in a disc separator are given.
Article
Chemistry, Analytical
Malvina Supper, Virginia Birner, Lukas Gromotka, Wolfgang Peukert, Malte Kaspereit
Summary: Alternate pumping chromatography is used to obtain high purity glutathione-stabilized gold nanoclusters with atomic precision from synthesized mixtures. Anion exchange chromatography is applied to isolate a single cluster, Au10GSH10, as well as two different clusters simultaneously (Au25GSH(18) and Au(29)GSH(20)). Trace amounts of Au(18)GSH(14) are successfully enriched. A simple design procedure allows for the use of columns with different retention behavior. Successful experiments with large injection amounts confirm the potential of this concept for preparative-scale productions of high-quality nanoparticulate products.
Article
Engineering, Chemical
Simon Assmann, Franz J. T. Huber, Stefan Will
Summary: Wide-angle light scattering was used for in situ measurements of droplet and nanoparticle size distributions during the synthesis process. The addition of different precursors led to altered evaporation behavior and different types of particle formations.
Article
Engineering, Chemical
Francisco J. Higuera, Juan Fernandez de la Mora
Summary: This study investigates a particle condensation device that uses cold and warm humid air streams to achieve water vapor condensation. Compared to existing water condensation particle counters, this configuration offers advantages such as variable saturation ratio, accelerated penetration of water vapor, and a relatively uniform saturation field.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Brijal Prajapati, Vishal Dharaiya, Manoranjan Sahu, Chandra Venkatraman, Pratim Biswas, Kajal Yadav, Delwin Pullokaran, Ramya Sunder Raman, Ruqia Bhat, Tanveer Ahmad Najar, Arshid Jehangir
Summary: This study evaluated the performance of a low-cost particulate matter sensor and proposed a physics-based calibration method. The results showed that the physics-based calibration approach performed better compared to statistical models at both observation sites.
JOURNAL OF AEROSOL SCIENCE
(2024)
Correction
Engineering, Chemical
N. Searle, K. Kaur, K. Kelly
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Tianyu Cen, Laura Torrent, Andrea Testino, Christian Ludwig
Summary: In this study, a hyphenated setup consisting of a rotating disk diluter (RDD) with spICP-MS (RDDspICP-MS) was used for online sampling and characterization of metallic nanoparticles (NPs) in ambient pressure aerosols. The RDD allowed for constant flow rate sampling of aerosols and adjusting the dilution ratio for different particle number concentrations (PNCs). The feasibility of this setup was tested with different sizes of AuNPs in argon-based and air-based aerosols, and the results showed a lower limit of detection for number concentration. The capability of the setup to accurately investigate multi-modal samples and the interference of ionic species was also demonstrated.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
A. Valenzuela, E. Bazo, R. A. Rica, L. Alados-Arboledas, F. J. Olmo-Reyes
Summary: This article introduces a method to measure the extinction cross section of levitated particles using an electrodynamic trap and double-cavity ring down spectroscopy technique, and demonstrates the potential of this method in 1,2,6-hexanetriol particles through simulations and experiments. Unlike traditional methods, this technique provides crucial information about the extinction cross section of sodium chloride particles during dehydration and hydration processes.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Shadi Yaqoubi, Mohaddese Sokuti, Sahand Mazloum-Ravasan, Kofi Asare-Addo, Hamed Hamishehkar, Ali Nokhodchi
Summary: In this study, a modified version of ultrasonic spray pyrolysis was used to prepare salbutamol sulfate dry powder. The engineered particles showed suitable characteristics for effective drug delivery to the lungs and demonstrated acceptable aerosolization performance. This newly introduced method appears to be capable of producing dry powder formulations of different drugs without the need for surfactants or stabilizers.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Ashley L. Nord, Patrice Dosset, Pierre Slangen, Manouk Abkarian
Summary: Phonation has been found to be a potent transmission route for the COVID-19 virus. To control transmission, it is important to measure the amount of aerosols produced by speech. Researchers used digital in-line holography to overcome experimental challenges and successfully imaged the formation and deformation of saliva filaments in the mouth during speech, as well as the resulting aerosolized droplets.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Yating Wang, Yiyang Zhang, Zhu Fang, Xinxin Wu
Summary: The research investigates the energy dissipation in particle-wall collision with roughness using the finite element method. The results show that the presence of surface roughness leads to lower viscoelastic dissipation and higher restitution coefficient compared to a smooth surface. The collision time is identified as a key factor in predicting the energy dissipation.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Shaamrit Balendra, Akshay Kale, Julie Pongetti, Mohsen Kazemimanesh, Molly Haugen, Lee Weller, Adam Boies
Summary: The measurement of airborne particles is important for detecting and characterising air pollution, emissions, fire detection, occupational and climate impacts. However, current optical particle counters (OPCs) cannot measure ultrafine particles. This study explores the limitations of miniaturising a condensation particle counter (CPC) growth chamber and provides a toolkit for optimising the design of miniaturised CPC-GCs.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Markus Snellman, Namsoon Eom, Maria E. Messing, Knut Deppert, Chris Hogan
Summary: Segregated bimetallic nanoparticles, such as core-shell nanoparticles, have attracted widespread interest in various fields like biomedicine, catalysis, and optoelectronics. Aerosol technology provides an optimal platform for controlling the size, structure, and composition of nanoparticles, which are crucial parameters for tuning the material performance for specific applications. In this study, researchers developed a novel evaporator design that allows on-line coating of core particles with a shell directly in the gas phase. By utilizing a local heater, the researchers were able to decouple the heating process of the evaporating material from the aerosol particles, thereby limiting core-shell alloying. The resulting core-shell particle formation with controllable shell thickness was demonstrated using evaporation of zinc onto core particles of gold, tin, and bismuth. Simple models were also discussed to explain the observed growth process inside the evaporator and the formation of the shell.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Kentaro Misawa, Yuto Kasai
Summary: In this study, the laser-induced fluorescence technique was used to observe scattered and fluorescent signals from fluorescent polystyrene latex particles. The ratio of fluorescence to scattered signal intensities was found to be almost equal for particles of the same size, allowing for the separate observation of mixed-size fluorescent particles. Relative fluorescence intensities were obtained by incorporating ratios of fluorescence to scattered signal and relative scattered signal intensities.
JOURNAL OF AEROSOL SCIENCE
(2024)
Article
Engineering, Chemical
Sripriya Nannu Shankar, William B. Vass, John A. Lednicky, Tracey Logan, Rebeccah L. Messcher, Arantzazu Eiguren-Fernandez, Stavros Amanatidis, Tara Sabo-Attwood, Chang-Yu Wu
Summary: This study introduces a testing system that allows for direct exposure of aerosolized viruses onto host cells. By collecting particles of different sizes and analyzing them, researchers obtained information on the concentration and viability of the virus at different particle sizes.
JOURNAL OF AEROSOL SCIENCE
(2024)
