A Combined SAXS/SANS Study for the in Situ Characterization of Ligand Shells on Small Nanoparticles: The Case of ZnO

Journal article
(Original article)

Publication Details

Author(s): Schindler T, Schmiele M, Schmutzler T, Kassar T, Segets D, Peukert W, Radulescu A, Kriele A, Gilles R, Unruh T
Journal: Langmuir
Publisher: American Chemical Society
Publication year: 2015
Volume: 31
Journal issue: 37
Pages range: 10130-10136
ISSN: 0743-7463
eISSN: 1520-5827
Language: English


ZnO nanoparticles (NPs) have great potential for their use in, e.g., thin film solar cells due to their electro-optical properties adjustable on the nanoscale. Therefore, the production of well-defined NPs is of major interest. For a targeted production process, the knowledge of the stabilization layer of the NPs during and after their formation is of particular importance. For the study of the stabilizer layer of ZnO NPs prepared in a wet chemical synthesis from zinc acetate, only ex situ studies have been performed so far. An acetate layer bound to the surface of the dried NPs was found; however, an in situ study which addresses the stabilizing layer surrounding the NPs in a native dispersion was missing. By the combination of small angle scattering with neutrons and X-rays (SANS and SAXS) for the same sample, we are now able to observe the acetate shell in situ for the first time. In addition, the changes of this shell could be followed during the ripening process for different temperatures. With increasing size of the ZnO core (dcore) the surrounding shell (dshell) becomes larger, and the acetate concentration within the shell is reduced. For all samples, the shell thickness was found to be larger than the maximum extension of an acetate molecule with acetate concentrations within the shell below 50 vol %. Thus, there is not a monolayer of acetate molecules that covers the NPs but rather a swollen shell of acetate ions. This shell is assumed to hinder the growth of the NPs to larger macrostructures. In addition, we found that the partition coefficient μ between acetate in the shell surrounding the NPs and the total amount of acetate in the solution is about 10% which is in good agreement with ex situ data determined by thermogravimetric analysis.

FAU Authors / FAU Editors

Kassar, Thaer
Professur für Nanomaterialcharakterisierung (Streumethoden)
Peukert, Wolfgang Prof. Dr.-Ing.
Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik
Schindler, Torben
Professur für Nanomaterialcharakterisierung (Streumethoden)
Schmiele, Martin
Professur für Nanomaterialcharakterisierung (Streumethoden)
Schmutzler, Tilo
Professur für Nanomaterialcharakterisierung (Streumethoden)
Segets, Doris Dr.-Ing.
Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik
Unruh, Tobias Prof. Dr.
Professur für Nanomaterialcharakterisierung (Streumethoden)

Additional Organisation
Graduiertenkolleg 1896/2 In situ Mikroskopie mit Elektronen, Röntgenstrahlen und Rastersonden
Exzellenz-Cluster Engineering of Advanced Materials
Interdisziplinäres Zentrum, Center for Nanoanalysis and Electron Microscopy (CENEM)

External institutions
Forschungszentrum Jülich GmbH (FZJ)
Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung GmbH (HZG)

How to cite

Schindler, T., Schmiele, M., Schmutzler, T., Kassar, T., Segets, D., Peukert, W.,... Unruh, T. (2015). A Combined SAXS/SANS Study for the in Situ Characterization of Ligand Shells on Small Nanoparticles: The Case of ZnO. Langmuir, 31(37), 10130-10136. https://dx.doi.org/10.1021/acs.langmuir.5b02198

Schindler, Torben, et al. "A Combined SAXS/SANS Study for the in Situ Characterization of Ligand Shells on Small Nanoparticles: The Case of ZnO." Langmuir 31.37 (2015): 10130-10136.


Last updated on 2019-03-06 at 17:00