Aerosol Synthesis and Characterization of Heterogeneous Bimetallic Nanoparticles
Syntes och Karaktärisering av Heterogena Bimetalliska Nanopartiklar med Aerosolteknologi
Author
Summary, in English
the product, and reduced waste from the process.
The two main approaches that have been developed in this work to create bimetallic heterogenous nanoparticles, surface segregation and condensational growth, both use spark ablation as the material source. From the optical emission in the electrical discharges, we use machine learning to determine the composition of bimetallic AuAg nanoparticles. Thermally induced surface segregation in CuAg agglomerates forming Janus and core-shell nanoparticles have been studied on- and off-line with aerosol metrology and electron microscopy. Compared to analogue works where the particles sit on a substrate, the aerosol phase is ideal to study surface segregation of “free” nanostructures. A more general route toward arbitrary metal-metal core-shell combinations is explored with condensational growth by thermal evaporation and photolysis. To understand the condensation inside a custom thermal evaporator designed in this work, a novel approach to measure the residence time distribution of aerosol nanoparticles is presented. Condensational growth of aerosol nanoparticles by
photolysis of metal-organic precursors is a new route that can be carried out at room temperature. The process therefore allows for formation of core-shell particles of miscible materials and avoids thermophoretic losses of particles experienced in conventional thermal evaporation.
Combining on-line compositional monitoring with the unique, precursor-less
pathways to create heterogeneous nanoparticles that aerosol technology enables, this thesis is a step toward more sustainable synthesis of tailored bimetallic nanostructures with applications in, for instance, catalysis, sensors, and electronics.
Department/s
Publishing year
2023-11-07
Language
English
Full text
- Available as PDF - 12 MB
- Download statistics
Document type
Dissertation
Publisher
Department of Physics, Lund University
Topic
- Nano Technology
- Condensed Matter Physics
Keywords
- nanoparticles
- core-shell
- Janus nanoparticles
- aerosol technology
- Fysicumarkivet A:2023 Snellman
- Nanopartiklar
- kärna-skal
- Januspartiklar
- aerosolteknologi
Status
Published
Project
- Undersökning av sinterprocesser genom studier av atomernas dynamik mellan nanopartiklar vid uppvärmning
- Core@shell nanoparticles with precisely controlled shells
- Aerosol Synthesis and Characterization of Heterogeneous Bimetallic Nanoparticles
ISBN/ISSN/Other
- ISBN: 978-91-8039-875-6
- ISBN: 978-91-8039-874-9
Defence date
1 December 2023
Defence time
09:15
Defence place
Lecture Hall Rydbergsalen, Department of Physics, Sölvegatan 14, Faculty of Engineering LTH, Lund University, Lund.
Opponent
- Martin Seipenbusch (Dr.)