Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Time-resolved analysis of nanoparticle composition from alloyed feedstocks

Jönsson, Linnéa LU ; Olszok, Vinzent ; Kohut, Attila ; Eriksson, Axel LU orcid ; Weber, Alfred and Messing, Maria LU (2025) European Aerosol Conference 2025
Abstract
Since its development in the 1980s, spark ablation has been widely used to produce nanoparticles (NPs) in the aerosol phase, effectively eliminating surface contamination common in other generation methods (Schmitt-Ott, 2019). This is a significant advantage, as the surface of NPs plays a crucial role in applications such as sensing and catalysis. Additionally, spark ablation enables the production of bimetallic NPs, combining the properties of two elements—often resulting in superior performance compared to individual constituents.

A common method for synthesizing multi-element NPs via spark ablation is using alloyed feedstock materials with the desired composition. In this process, sparks locally evaporate the feedstock, which... (More)
Since its development in the 1980s, spark ablation has been widely used to produce nanoparticles (NPs) in the aerosol phase, effectively eliminating surface contamination common in other generation methods (Schmitt-Ott, 2019). This is a significant advantage, as the surface of NPs plays a crucial role in applications such as sensing and catalysis. Additionally, spark ablation enables the production of bimetallic NPs, combining the properties of two elements—often resulting in superior performance compared to individual constituents.

A common method for synthesizing multi-element NPs via spark ablation is using alloyed feedstock materials with the desired composition. In this process, sparks locally evaporate the feedstock, which then rapidly cools, leading to nucleation and NP formation. It is generally assumed that the resulting particles retain the same elemental ratio as the alloyed feedstock. This assumption was recently confirmed for the Ag-Au system, where a strong correlation between feedstock and particle composition was observed (Jönsson, 2024). However, a 1989 study by Watters et al. on the Cu-Zn system suggested a slight deviation, with Zn enrichment in the produced NPs. Surface analysis of the electrode revealed a noticeable depletion of Zn compared to the original feedstock ratio. Surprisingly, this finding has remained largely overlooked since its initial report. The Cu-Zn system, commonly known as brass, is widely used in industry. Despite the differences in melting points (Cu: 1083°C, Zn: 419°C) and the high vapor pressure of Zn, the system exhibits several stable phases. To gain a deeper understanding of spark ablation from alloyed electrodes, this work focuses on the Cu-Zn system—an ideal model due to its contrasting elemental properties.
Preliminary findings for the Cu-Zn system align with the observations made by Watters et al. Both the unsparked and sparked electrode surfaces were analysed using scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), see Figure 1. After approximately 5 hours of sparking, the Zn content on the electrode surface had significantly decreased. Based on these results, we hypothesize that the composition of the generated NPs evolves over time—an effect that has not been previously reported for alloyed electrodes in spark ablation.

This study will explore the Cu-Zn system as a source for NP production via spark ablation using time-resolved methods. NPs will be generated from three alloyed CuZn feedstocks (Cu25Zn75, Cu50Zn50, and Cu75Zn25) as well as pure Cu and Zn electrodes. The composition of the produced NPs will be analysed using three time-resolved techniques that proven effective for tracking elemental composition over time: x-ray fluorescence (XRF) (Franzén, 2023), inductively coupled plasma mass spectrometry (ICP-MS) (Olszok, 2024), and optical emission spectroscopy (OES) (Kohut, 2023). These findings have significant implications for the spark ablation community, directly challenging the long-held assumption that NPs inherit the exact composition of their alloyed feedstock. By uncovering new dynamics in NP formation, this work opens new possibilities for precise control over bimetallic NP synthesis, with broad relevance for catalysis, sensing, and beyond.

This work is supported by the Swedish Foundation for Strategic Research (FFL180282), the Swedish Research Council (2019-04970), the Royal Physiographic Society in Lund, NanoLund, the National Research Development and Innovation Fund of Hungary (TKP2021-NVA-19).

Schmitt-Ott, A. et al (2019). Jenny Standford Publishing.
Jönsson, L. et al (2024). Journal of Aerosol Science, 177.
Watters, R. L. et al (1989). Analytical Chemistry, 61.
Franzén, S. et al (2023). Nanoscale Advances, 5.
Olszok, V. et al (2024). Nanoscale Advances, 6.
Kohut, A. et al (2023). Applied Spectroscopy, 77. (Less)
Please use this url to cite or link to this publication:
author
; ; ; ; and
organization
publishing date
type
Contribution to conference
publication status
published
subject
conference name
European Aerosol Conference 2025
conference location
Lecce, Italy
conference dates
2025-08-31 - 2025-09-05
language
English
LU publication?
yes
id
fba59245-2936-498c-99b4-8667f4c98cd6
date added to LUP
2025-12-01 13:43:58
date last changed
2025-12-09 08:09:58
@misc{fba59245-2936-498c-99b4-8667f4c98cd6,
  abstract     = {{Since its development in the 1980s, spark ablation has been widely used to produce nanoparticles (NPs) in the aerosol phase, effectively eliminating surface contamination common in other generation methods (Schmitt-Ott, 2019). This is a significant advantage, as the surface of NPs plays a crucial role in applications such as sensing and catalysis. Additionally, spark ablation enables the production of bimetallic NPs, combining the properties of two elements—often resulting in superior performance compared to individual constituents.<br/><br/>A common method for synthesizing multi-element NPs via spark ablation is using alloyed feedstock materials with the desired composition. In this process, sparks locally evaporate the feedstock, which then rapidly cools, leading to nucleation and NP formation. It is generally assumed that the resulting particles retain the same elemental ratio as the alloyed feedstock. This assumption was recently confirmed for the Ag-Au system, where a strong correlation between feedstock and particle composition was observed (Jönsson, 2024). However, a 1989 study by Watters et al. on the Cu-Zn system suggested a slight deviation, with Zn enrichment in the produced NPs. Surface analysis of the electrode revealed a noticeable depletion of Zn compared to the original feedstock ratio. Surprisingly, this finding has remained largely overlooked since its initial report. The Cu-Zn system, commonly known as brass, is widely used in industry. Despite the differences in melting points (Cu: 1083°C, Zn: 419°C) and the high vapor pressure of Zn, the system exhibits several stable phases. To gain a deeper understanding of spark ablation from alloyed electrodes, this work focuses on the Cu-Zn system—an ideal model due to its contrasting elemental properties.<br/>Preliminary findings for the Cu-Zn system align with the observations made by Watters et al. Both the unsparked and sparked electrode surfaces were analysed using scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), see Figure 1. After approximately 5 hours of sparking, the Zn content on the electrode surface had significantly decreased. Based on these results, we hypothesize that the composition of the generated NPs evolves over time—an effect that has not been previously reported for alloyed electrodes in spark ablation.<br/><br/>This study will explore the Cu-Zn system as a source for NP production via spark ablation using time-resolved methods. NPs will be generated from three alloyed CuZn feedstocks (Cu25Zn75, Cu50Zn50, and Cu75Zn25) as well as pure Cu and Zn electrodes. The composition of the produced NPs will be analysed using three time-resolved techniques that proven effective for tracking elemental composition over time: x-ray fluorescence (XRF) (Franzén, 2023), inductively coupled plasma mass spectrometry (ICP-MS) (Olszok, 2024), and optical emission spectroscopy (OES) (Kohut, 2023). These findings have significant implications for the spark ablation community, directly challenging the long-held assumption that NPs inherit the exact composition of their alloyed feedstock. By uncovering new dynamics in NP formation, this work opens new possibilities for precise control over bimetallic NP synthesis, with broad relevance for catalysis, sensing, and beyond.<br/><br/>This work is supported by the Swedish Foundation for Strategic Research (FFL180282), the Swedish Research Council (2019-04970), the Royal Physiographic Society in Lund, NanoLund, the National Research Development and Innovation Fund of Hungary (TKP2021-NVA-19).<br/><br/>Schmitt-Ott, A. et al (2019). Jenny Standford Publishing.<br/>Jönsson, L. et al (2024). Journal of Aerosol Science, 177. <br/>Watters, R. L. et al (1989). Analytical Chemistry, 61.<br/>Franzén, S. et al (2023). Nanoscale Advances, 5.<br/>Olszok, V. et al (2024). Nanoscale Advances, 6.<br/>Kohut, A. et al (2023). Applied Spectroscopy, 77.}},
  author       = {{Jönsson, Linnéa and Olszok, Vinzent and Kohut, Attila and Eriksson, Axel and Weber, Alfred and Messing, Maria}},
  language     = {{eng}},
  month        = {{10}},
  title        = {{Time-resolved analysis of nanoparticle composition from alloyed feedstocks}},
  year         = {{2025}},
}