ZnO Nanoparticle Formation from the Molecular Precursor [MeZnOtBu](4) by Ozone Treatment in Ionic Liquids: in-situ Vibrational Spectroscopy in an Ultrahigh Vacuum Environment

Bauer T, Voggenreiter M, Xu T, Wähler T, Agel F, Pohako-Esko K, Schulz P, Döpper T, Görling A, Polarz S, Wasserscheid P, Libuda J (2017)

Publication Language: English

Publication Status: Published

Publication Type: Journal article

Publication year: 2017

Journal

Zeitschrift für Anorganische und Allgemeine Chemie Wiley

Publisher: WILEY-V C H VERLAG GMBH

Book Volume: 643

Pages Range: 31-40

Journal Issue: 1

DOI: 10.1002/zaac.201600345

Abstract

As reported previously, novel ZnO nanostructures can be grown by oxidation of [MeZnOtBu](4) building blocks with O-3 in ionic liquids (ILs). In this study, we have explored the role of the IL during ZnO formation by in-situ infrared reflection absorption spectroscopy (IRAS) in ultrahigh vacuum (UHV). [MeZnOtBu](4) and [C(2)C(1)Im][OTf] were (co-)deposited as thin films by physical vapor deposition (PVD) onto Au(111), separately or simultaneously. The IR spectrum of [MeZnOtBu](4) was analyzed between 300 and 4000 cm(-1) based on calculated spectra from density-functional theory (DFT). Spectral changes in the IL-related bands during the thermal treatment of [MeZnOtBu](4) in [C(2)C(1)Im][OTf] indicate the loss of the precursor ligands and the interaction of the IL with the growing ZnO aggregates. The films were treated with ozone (10(-6) mbar) in UHV and the spectral changes were monitored in-situ by IRAS. Slow ozonolysis of [C(2)C(1)Im][OTf] is observed. Spectroscopically we identify the primary ozonide formed by addition of O-3 to [C(2)C(1)Im](+) and suggest a reaction mechanism, which leads to a biuret derivative. Upon ozone treatment of mixed [MeZnOtBu](4)/[C(2)C(1)Im][OTf] films, ZnO aggregates are formed at the IL/vacuum interface. Ozonolysis of [C(2)C(1)Im][OTf] is suppressed. Upon annealing to 320 K, further ZnO aggregates are formed, leading to enclosure of [C(2)C(1)Im][OTf] in the ZnO film. At 380 K the IL is released from the mixed film. The pure [C(2)C(1)Im][OTf] desorbs at 420 K, leaving behind the ZnO phase.

Authors with CRIS profile

Tanja Retzer Lehrstuhl für Physikalische Chemie II Tao Xu Lehrstuhl für Physikalische Chemie II Tobias Wähler Lehrstuhl für Physikalische Chemie II Friederike Agel Lehrstuhl für Chemische Reaktionstechnik Kaija Pohako-Esko Lehrstuhl für Chemische Reaktionstechnik Peter Schulz Lehrstuhl für Chemische Reaktionstechnik Tibor Döpper Lehrstuhl für Theoretische Chemie Andreas Görling Lehrstuhl für Theoretische Chemie Peter Wasserscheid Lehrstuhl für Chemische Reaktionstechnik Jörg Libuda Professur für Physikalische Chemie

Involved external institutions

Universität Konstanz DE Germany (DE)

How to cite

APA:

Bauer, T., Voggenreiter, M., Xu, T., Wähler, T., Agel, F., Pohako-Esko, K.,... Libuda, J. (2017). ZnO Nanoparticle Formation from the Molecular Precursor [MeZnOtBu](4) by Ozone Treatment in Ionic Liquids: in-situ Vibrational Spectroscopy in an Ultrahigh Vacuum Environment. Zeitschrift für Anorganische und Allgemeine Chemie, 643(1), 31-40. https://doi.org/10.1002/zaac.201600345

MLA:

Bauer, Tanja, et al. "ZnO Nanoparticle Formation from the Molecular Precursor [MeZnOtBu](4) by Ozone Treatment in Ionic Liquids: in-situ Vibrational Spectroscopy in an Ultrahigh Vacuum Environment." Zeitschrift für Anorganische und Allgemeine Chemie 643.1 (2017): 31-40.

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