Determining the Thickness and Completeness of the Shell of Polymer Core-Shell Nanoparticles by X-ray Photoelectron Spectroscopy, Secondary Ion Mass Spectrometry, and Transmission Scanning Electron Microscopy

Anja Müller, Thomas Heinrich, Sven Tougaard, Wolfgang S.M. Werner, Martin Hronek, Valentin Kunz, Jörg Radnik, Jörg M. Stockmann, Vasile Dan Hodoroaba, Sigrid Benemann, Nithiya Nirmalananthan-Budau, Daniel Geißler, Katia Sparnacci, Wolfgang E.S. Unger*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

30 Downloads (Pure)

Abstract

Core-shell nanoparticles (CSNPs) have become indispensable in various industrial applications. However, their real internal structure usually deviates from an ideal core-shell structure. To control how the particles perform with regard to their specific applications, characterization techniques are required that can distinguish an ideal from a nonideal morphology. In this work, we investigated poly(tetrafluoroethylene)-poly(methyl methacrylate) (PTFE-PMMA) and poly(tetrafluoroethylene)-polystyrene (PTFE-PS) polymer CSNPs with a constant core diameter (45 nm) but varying shell thicknesses (4-50 nm). As confirmed by transmission scanning electron microscopy (T-SEM), the shell completely covers the core for the PTFE-PMMA nanoparticles, while the encapsulation of the core by the shell material is incomplete for the PTFE-PS nanoparticles. X-ray photoelectron spectroscopy (XPS) was applied to determine the shell thickness of the nanoparticles. The software SESSA v2.0 was used to analyze the intensities of the elastic peaks, and the QUASES software package was employed to evaluate the shape of the inelastic background in the XPS survey spectra. For the first time, nanoparticle shell thicknesses are presented, which are exclusively based on the analysis of the XPS inelastic background. Furthermore, principal component analysis (PCA)-assisted time-of-flight secondary-ion mass spectrometry (ToF-SIMS) of the PTFE-PS nanoparticle sample set revealed a systematic variation among the samples and, thus, confirmed the incomplete encapsulation of the core by the shell material. As opposed to that, no variation is observed in the PCA score plots of the PTFE-PMMA nanoparticle sample set. Consequently, the complete coverage of the core by the shell material is proved by ToF-SIMS with a certainty that cannot be achieved by XPS and T-SEM.

Original languageEnglish
JournalJournal of Physical Chemistry C
Volume123
Issue number49
Pages (from-to)29765-29775
Number of pages11
ISSN1932-7447
DOIs
Publication statusPublished - 12. Nov 2019

Fingerprint

completeness
Secondary ion mass spectrometry
Polytetrafluoroethylenes
secondary ion mass spectrometry
polytetrafluoroethylene
Polymers
X ray photoelectron spectroscopy
photoelectron spectroscopy
Nanoparticles
Transmission electron microscopy
Polymethyl Methacrylate
nanoparticles
transmission electron microscopy
Scanning electron microscopy
scanning electron microscopy
polymers
Polystyrenes
x rays
Polymethyl methacrylates
polymethyl methacrylate

Cite this

Müller, Anja ; Heinrich, Thomas ; Tougaard, Sven ; Werner, Wolfgang S.M. ; Hronek, Martin ; Kunz, Valentin ; Radnik, Jörg ; Stockmann, Jörg M. ; Hodoroaba, Vasile Dan ; Benemann, Sigrid ; Nirmalananthan-Budau, Nithiya ; Geißler, Daniel ; Sparnacci, Katia ; Unger, Wolfgang E.S. / Determining the Thickness and Completeness of the Shell of Polymer Core-Shell Nanoparticles by X-ray Photoelectron Spectroscopy, Secondary Ion Mass Spectrometry, and Transmission Scanning Electron Microscopy. In: Journal of Physical Chemistry C. 2019 ; Vol. 123, No. 49. pp. 29765-29775.
@article{7b83b4c3844948d1b320ea5d95a7a080,
title = "Determining the Thickness and Completeness of the Shell of Polymer Core-Shell Nanoparticles by X-ray Photoelectron Spectroscopy, Secondary Ion Mass Spectrometry, and Transmission Scanning Electron Microscopy",
abstract = "Core-shell nanoparticles (CSNPs) have become indispensable in various industrial applications. However, their real internal structure usually deviates from an ideal core-shell structure. To control how the particles perform with regard to their specific applications, characterization techniques are required that can distinguish an ideal from a nonideal morphology. In this work, we investigated poly(tetrafluoroethylene)-poly(methyl methacrylate) (PTFE-PMMA) and poly(tetrafluoroethylene)-polystyrene (PTFE-PS) polymer CSNPs with a constant core diameter (45 nm) but varying shell thicknesses (4-50 nm). As confirmed by transmission scanning electron microscopy (T-SEM), the shell completely covers the core for the PTFE-PMMA nanoparticles, while the encapsulation of the core by the shell material is incomplete for the PTFE-PS nanoparticles. X-ray photoelectron spectroscopy (XPS) was applied to determine the shell thickness of the nanoparticles. The software SESSA v2.0 was used to analyze the intensities of the elastic peaks, and the QUASES software package was employed to evaluate the shape of the inelastic background in the XPS survey spectra. For the first time, nanoparticle shell thicknesses are presented, which are exclusively based on the analysis of the XPS inelastic background. Furthermore, principal component analysis (PCA)-assisted time-of-flight secondary-ion mass spectrometry (ToF-SIMS) of the PTFE-PS nanoparticle sample set revealed a systematic variation among the samples and, thus, confirmed the incomplete encapsulation of the core by the shell material. As opposed to that, no variation is observed in the PCA score plots of the PTFE-PMMA nanoparticle sample set. Consequently, the complete coverage of the core by the shell material is proved by ToF-SIMS with a certainty that cannot be achieved by XPS and T-SEM.",
author = "Anja M{\"u}ller and Thomas Heinrich and Sven Tougaard and Werner, {Wolfgang S.M.} and Martin Hronek and Valentin Kunz and J{\"o}rg Radnik and Stockmann, {J{\"o}rg M.} and Hodoroaba, {Vasile Dan} and Sigrid Benemann and Nithiya Nirmalananthan-Budau and Daniel Gei{\ss}ler and Katia Sparnacci and Unger, {Wolfgang E.S.}",
year = "2019",
month = "11",
day = "12",
doi = "10.1021/acs.jpcc.9b09258",
language = "English",
volume = "123",
pages = "29765--29775",
journal = "The Journal of Physical Chemistry Part C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "49",

}

Müller, A, Heinrich, T, Tougaard, S, Werner, WSM, Hronek, M, Kunz, V, Radnik, J, Stockmann, JM, Hodoroaba, VD, Benemann, S, Nirmalananthan-Budau, N, Geißler, D, Sparnacci, K & Unger, WES 2019, 'Determining the Thickness and Completeness of the Shell of Polymer Core-Shell Nanoparticles by X-ray Photoelectron Spectroscopy, Secondary Ion Mass Spectrometry, and Transmission Scanning Electron Microscopy', Journal of Physical Chemistry C, vol. 123, no. 49, pp. 29765-29775. https://doi.org/10.1021/acs.jpcc.9b09258

Determining the Thickness and Completeness of the Shell of Polymer Core-Shell Nanoparticles by X-ray Photoelectron Spectroscopy, Secondary Ion Mass Spectrometry, and Transmission Scanning Electron Microscopy. / Müller, Anja; Heinrich, Thomas; Tougaard, Sven; Werner, Wolfgang S.M.; Hronek, Martin; Kunz, Valentin; Radnik, Jörg; Stockmann, Jörg M.; Hodoroaba, Vasile Dan; Benemann, Sigrid; Nirmalananthan-Budau, Nithiya; Geißler, Daniel; Sparnacci, Katia; Unger, Wolfgang E.S.

In: Journal of Physical Chemistry C, Vol. 123, No. 49, 12.11.2019, p. 29765-29775.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Determining the Thickness and Completeness of the Shell of Polymer Core-Shell Nanoparticles by X-ray Photoelectron Spectroscopy, Secondary Ion Mass Spectrometry, and Transmission Scanning Electron Microscopy

AU - Müller, Anja

AU - Heinrich, Thomas

AU - Tougaard, Sven

AU - Werner, Wolfgang S.M.

AU - Hronek, Martin

AU - Kunz, Valentin

AU - Radnik, Jörg

AU - Stockmann, Jörg M.

AU - Hodoroaba, Vasile Dan

AU - Benemann, Sigrid

AU - Nirmalananthan-Budau, Nithiya

AU - Geißler, Daniel

AU - Sparnacci, Katia

AU - Unger, Wolfgang E.S.

PY - 2019/11/12

Y1 - 2019/11/12

N2 - Core-shell nanoparticles (CSNPs) have become indispensable in various industrial applications. However, their real internal structure usually deviates from an ideal core-shell structure. To control how the particles perform with regard to their specific applications, characterization techniques are required that can distinguish an ideal from a nonideal morphology. In this work, we investigated poly(tetrafluoroethylene)-poly(methyl methacrylate) (PTFE-PMMA) and poly(tetrafluoroethylene)-polystyrene (PTFE-PS) polymer CSNPs with a constant core diameter (45 nm) but varying shell thicknesses (4-50 nm). As confirmed by transmission scanning electron microscopy (T-SEM), the shell completely covers the core for the PTFE-PMMA nanoparticles, while the encapsulation of the core by the shell material is incomplete for the PTFE-PS nanoparticles. X-ray photoelectron spectroscopy (XPS) was applied to determine the shell thickness of the nanoparticles. The software SESSA v2.0 was used to analyze the intensities of the elastic peaks, and the QUASES software package was employed to evaluate the shape of the inelastic background in the XPS survey spectra. For the first time, nanoparticle shell thicknesses are presented, which are exclusively based on the analysis of the XPS inelastic background. Furthermore, principal component analysis (PCA)-assisted time-of-flight secondary-ion mass spectrometry (ToF-SIMS) of the PTFE-PS nanoparticle sample set revealed a systematic variation among the samples and, thus, confirmed the incomplete encapsulation of the core by the shell material. As opposed to that, no variation is observed in the PCA score plots of the PTFE-PMMA nanoparticle sample set. Consequently, the complete coverage of the core by the shell material is proved by ToF-SIMS with a certainty that cannot be achieved by XPS and T-SEM.

AB - Core-shell nanoparticles (CSNPs) have become indispensable in various industrial applications. However, their real internal structure usually deviates from an ideal core-shell structure. To control how the particles perform with regard to their specific applications, characterization techniques are required that can distinguish an ideal from a nonideal morphology. In this work, we investigated poly(tetrafluoroethylene)-poly(methyl methacrylate) (PTFE-PMMA) and poly(tetrafluoroethylene)-polystyrene (PTFE-PS) polymer CSNPs with a constant core diameter (45 nm) but varying shell thicknesses (4-50 nm). As confirmed by transmission scanning electron microscopy (T-SEM), the shell completely covers the core for the PTFE-PMMA nanoparticles, while the encapsulation of the core by the shell material is incomplete for the PTFE-PS nanoparticles. X-ray photoelectron spectroscopy (XPS) was applied to determine the shell thickness of the nanoparticles. The software SESSA v2.0 was used to analyze the intensities of the elastic peaks, and the QUASES software package was employed to evaluate the shape of the inelastic background in the XPS survey spectra. For the first time, nanoparticle shell thicknesses are presented, which are exclusively based on the analysis of the XPS inelastic background. Furthermore, principal component analysis (PCA)-assisted time-of-flight secondary-ion mass spectrometry (ToF-SIMS) of the PTFE-PS nanoparticle sample set revealed a systematic variation among the samples and, thus, confirmed the incomplete encapsulation of the core by the shell material. As opposed to that, no variation is observed in the PCA score plots of the PTFE-PMMA nanoparticle sample set. Consequently, the complete coverage of the core by the shell material is proved by ToF-SIMS with a certainty that cannot be achieved by XPS and T-SEM.

U2 - 10.1021/acs.jpcc.9b09258

DO - 10.1021/acs.jpcc.9b09258

M3 - Journal article

AN - SCOPUS:85075620737

VL - 123

SP - 29765

EP - 29775

JO - The Journal of Physical Chemistry Part C

JF - The Journal of Physical Chemistry Part C

SN - 1932-7447

IS - 49

ER -