Investigation of core-shell nanoparticles using scanning transmission x-ray microscopy (STXM)
- A scanning transmission x-ray microscopy (STXM) based methodology is introduced for determining the dimensions (shell thickness, core and total diameter) of core-shell nanoparticles which exhibit a strong x-ray absorption contrast and a well-defined interface between core and shell material. A low radiation dosage during data acquisition and, therefore, less x-ray beam induced damage of the sample is achieved by recording STXM images only at two predetermined energies of maximum absorption contrast, instead of recording a stack of images across the whole absorption edge. A model core-shell nanoparticle, polytetrafluoroethylene (PTFE) cores with polystyrene (PS) shell, is used for demonstration. Near edge x-ray absorption fine structure (NEXAFS) spectroscopy confirms the significant difference in x-ray absorption behavior between PTFE and PS. Additionally, due to the insolubility of styrene in PTFE a well-defined interface between particle core and shell is expected. In order toA scanning transmission x-ray microscopy (STXM) based methodology is introduced for determining the dimensions (shell thickness, core and total diameter) of core-shell nanoparticles which exhibit a strong x-ray absorption contrast and a well-defined interface between core and shell material. A low radiation dosage during data acquisition and, therefore, less x-ray beam induced damage of the sample is achieved by recording STXM images only at two predetermined energies of maximum absorption contrast, instead of recording a stack of images across the whole absorption edge. A model core-shell nanoparticle, polytetrafluoroethylene (PTFE) cores with polystyrene (PS) shell, is used for demonstration. Near edge x-ray absorption fine structure (NEXAFS) spectroscopy confirms the significant difference in x-ray absorption behavior between PTFE and PS. Additionally, due to the insolubility of styrene in PTFE a well-defined interface between particle core and shell is expected. In order to validate the STXM results, both the naked PTFE cores as well as the complete core-shell nanoparticles are examined by scanning electron microscopy (SEM). The introduced STXM based methodology yields particle dimensions in good agreement with the SEM results (deviation equal or less than 10%) and provides additional information such as the position of the particle core which cannot be extracted from a SEM micrograph.…


| Autor*innen: | Anja MüllerORCiD |
|---|---|
| Koautor*innen: | Sufal Swaraj, Katia Sparnacci, Andreas Lippitz, Wolfgang UngerORCiD |
| Dokumenttyp: | Vortrag |
| Veröffentlichungsform: | Präsentation |
| Sprache: | Englisch |
| Jahr der Erstveröffentlichung: | 2018 |
| DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
| Freie Schlagwörter: | Core-shell nanoparticles; PS; PTFE; SEM; STXM |
| Veranstaltung: | DPG-Frühjahrstagung der Sektion Kondensierte Materie gemeinsam mit der EPS |
| Veranstaltungsort: | Berlin, Germany |
| Beginndatum der Veranstaltung: | 11.03.2018 |
| Enddatum der Veranstaltung: | 16.03.2018 |
| Bemerkung: | Geburtsname von Müller, Anja: Hermanns, A. - Birth name of Müller, Anja: Hermanns, A. |
| Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
| Datum der Freischaltung: | 10.04.2018 |
| Referierte Publikation: | Nein |
| Eingeladener Vortrag (wissenschaftliche Konferenzen): | Nein |

