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Laser-Induced Dielectric Breakdown as a Novel Method for Obtaining Isotopically Enriched Nanoscale Substances

  • The possibility of obtaining high-purity, isotopically modified and nanostructured elemental substances 29Si, 98Mo, and 100Mo, as well as 98Mox10By compounds from volatile halides under conditions of laser optical breakdown of a pulsed Nd:YAG laser is shown. Currently, research in the field of developing new methods for obtaining high-purity, isotopically modified and nanostructured substances is being actively conducted. Interest in Si and Mo combining these forms has noticeably increased. In nuclear medicine, 29Si-enriched nanoparticles can be used as contrast agents in magnetic resonance imaging (MRI), and 98Mo and 100Mo isotopes can be used to obtain the unstable 99mTc radioisotope. These applications do not require large amounts of isotopically modified Si and Mo. Their obtaining belongs to the problems of small chemistry. When obtaining isotopically modified Si and Mo, it is expedient to use their volatile fluorides, for which technologies of isotope enrichment and deepThe possibility of obtaining high-purity, isotopically modified and nanostructured elemental substances 29Si, 98Mo, and 100Mo, as well as 98Mox10By compounds from volatile halides under conditions of laser optical breakdown of a pulsed Nd:YAG laser is shown. Currently, research in the field of developing new methods for obtaining high-purity, isotopically modified and nanostructured substances is being actively conducted. Interest in Si and Mo combining these forms has noticeably increased. In nuclear medicine, 29Si-enriched nanoparticles can be used as contrast agents in magnetic resonance imaging (MRI), and 98Mo and 100Mo isotopes can be used to obtain the unstable 99mTc radioisotope. These applications do not require large amounts of isotopically modified Si and Mo. Their obtaining belongs to the problems of small chemistry. When obtaining isotopically modified Si and Mo, it is expedient to use their volatile fluorides, for which technologies of isotope enrichment and deep purification are well developed. These halides have high chemical and thermal stability; therefore, plasma-chemical methods based on the plasma of a pulsed discharge generated by laser breakdown can be promising for separating 29Si, 98Mo, and 100Mo from them. Laser breakdown in H2+Ar+SiF4 and H2+Ar+MoF6 mixtures in various stoichiometric ratios in the pressure range 30–760 Torr was carried out using a pulsed Nd:YAG laser. The pulse duration at a wavelength of 1064 nm was 15 ns, the repetition rate was 5 Hz. A pulse energy of 800 mJ was focused by a lens with a focal length of 5 cm. The energy density at the focus was 26 J/cm3 . It has been shown that when using a mixture based on 29SiF4, the sample contains a 29Si crystalline phase with an average grain size of 30–50 nm (Fig. 1a). When using a mixture based on 98MoF6, the sample contains a 98Mo crystalline phase with an average grain size of 70–100 nm (Fig. 1b). In this type of gas discharge, the possibility of forming superhard materials, isotopically modified molybdenum borides, was also studied. These substances in the form of nanosized particles have improved tribological properties. After ablation of metallic Mo in the H2 + BF3 mixture, the main phase was MoB2 in the form of a nanodispersed powder with an average grain size of 100 nm (Fig. 1c) [1]. A technique for modeling gas-dynamic and thermal conditions in a low-temperature chemically active plasma induced by laser breakdown is proposed. Using computational experiments, the features of gas mixture heating and the formation of nanoparticles in the LIBS reactor were studiedzeige mehrzeige weniger

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Metadaten
Autor*innen:Igor Gornushkin, R. Kornev, A. Bulanov, A. Ermakov
Dokumenttyp:Posterpräsentation
Veröffentlichungsform:Präsentation
Sprache:Englisch
Jahr der Erstveröffentlichung:2023
Organisationseinheit der BAM:1 Analytische Chemie; Referenzmaterialien
1 Analytische Chemie; Referenzmaterialien / 1.3 Instrumentelle Analytik
DDC-Klassifikation:Naturwissenschaften und Mathematik / Chemie / Analytische Chemie
Freie Schlagwörter:Chemical vapor deposition; Isotopically enriched nanomaterials; Laser induced plasma
Themenfelder/Aktivitätsfelder der BAM:Chemie und Prozesstechnik
Veranstaltung:17the International Conference on Laser Applications in Life Sciences
Veranstaltungsort:Mugla, Turkey
Beginndatum der Veranstaltung:15.10.2023
Enddatum der Veranstaltung:17.10.2023
Verfügbarkeit des Dokuments:Datei im Netzwerk der BAM verfügbar ("Closed Access")
Datum der Freischaltung:28.11.2023
Referierte Publikation:Nein
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