Original title:
Origin of nanopartical nuclei: Formation of dimers in pulse magnetron discharges
Authors:
Čurda, P. ; Hippler, Rainer ; Čada, Martin ; Straňák, V. ; Hubička, Zdeněk Document type: Papers Conference/Event: NANOCON 2023 - International Conference on Nanomaterials - Research & Application /15./, Brno (CZ), 20231018
Year:
2024
Language:
eng Abstract:
The study focuses on the synthesis of metallic nanoparticles (NPs) by gas aggregation of magnetron sputtered atoms. Such NPs have gained significant attention because of their wide potential applications. For that reason, the cost-efficient and energy-effective synthesis of NPs is wanted. The growth of NPs follows processes of dimer seed nucleation, atom adsorption, and coagulation, the initial nucleation of the seed, i.e., dimer origin, is considered the most limiting part of growth. Hence, it is believed, that if dimer seeds are produced effectively, the NPs growth will follow this trend, too. Various pathways exist for the synthesis of diatomic molecules in magnetron sputtering. The three-body collision reactions, involving two metal and one gas atom M+M+G, suffer from relatively low reaction coefficients indicating practically negligible contribution of this reaction to dimer production. Two-body collision reactions, driven by ionization events and electron release, have gained significance due to their higher rate coefficients. However, direct sputtering of metal dimers from the target material offers straight forward and effective way that yields the highest and direct production of dimers M2. This study investigates pulsed magnetron discharges, namely the pulse repetition frequency and the pulse width, to reveal the optimal conditions for direct dimer sputtering. The dimer sputtering efficiency is estimated from energy-resolved mass spectroscopy measurements. Overall, this study underscores the significance of fine-tuning production processes for diatomic molecules, offering a pathway to advanced nanoparticle synthesis.
Keywords:
dimer; energy-resolved mass spectrometry; gas aggregation synthesis; magnetron sputtering; nanoparticle Project no.: EF16_019/0000760 Funding provider: GA MŠk Host item entry: NANOCON 2023 Conference Proceedings, ISBN 978-80-88365-15-0, ISSN 2694-930X