Controlled Oxidation and Self-Passivation of Bimetallic Magnetic FeCr and FeMn Aerosol Nanoparticles

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift


Nanoparticle generation by aerosol methods, particularly spark ablation, has high potential for creating new material combinations with tailored magnetic properties. By combining elements into complex alloyed nanoparticles and controlling their size and structure, different magnetic properties can be obtained. In combination with controlled deposition, to ensure nanoparticle separation, it is possible to minimize interparticle interactions and measure the intrinsic magnetic property of the nanoparticles. Most magnetic materials are highly sensitive to oxygen, and it is therefore crucial to both understand and control the oxidation of magnetic nanoparticles. In this study, we have successfully generated oxidized, bimetallic FeCr and FeMn nanoparticles by spark ablation in combination with a compaction step and thoroughly characterized individual particles with aerosol instruments, transmission electron microscopy and synchrotron-based X-ray photoelectron spectroscopy. The generated nanoparticles had an almost identical transition-metal ratio to the electrodes used as seed materials. Further, we demonstrate how the carrier gas can be used to dictate the oxidation and how to alternate between self-passivated and entirely oxidized nanoparticles. We also discuss the complexity of compacting alloyed nanoparticles consisting of elements with different vapor pressures and how this will affect the composition. This knowledge will further the understanding of design and generation of complex alloyed nanoparticles based on transition metals using aerosol methods, especially for the size regime where a compaction step is needed. As a proof of concept, measurements using a magnetometer equipped with a superconducting quantum interference device were performed on samples with different particle coverages. These measurements show that the magnetic properties could be explored for both high and low surface coverages, which open a way for studies where interparticle interactions can be systematically controlled.


Enheter & grupper
Externa organisationer
  • University of Zurich
  • Paul Scherrer Institute

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Den kondenserade materiens fysik
Sidor (från-till)16083-16090
Antal sidor8
TidskriftJournal of Physical Chemistry C
Utgåva nummer26
StatusPublished - 2019 jun 10
Peer review utfördJa

Relaterad forskningsoutput

Calle Preger, 2020 okt 30, Lund: Department of Physics, Lund University.

Forskningsoutput: AvhandlingDoktorsavhandling (sammanläggning)

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