Spontaneous dissociation of Co₂(CO)₈ and autocatalytic growth of Co on SiO₂: A combined experimental and theoretical investigation
- We present experimental results and theoretical simulations of the adsorption behavior of the metal–organic precursor Co2(CO)8 on SiO2 surfaces after application of two different pretreatment steps, namely by air plasma cleaning or a focused electron beam pre-irradiation. We observe a spontaneous dissociation of the precursor molecules as well as autodeposition of cobalt on the pretreated SiO2 surfaces. We also find that the differences in metal content and relative stability of these deposits depend on the pretreatment conditions of the substrate. Transport measurements of these deposits are also presented. We are led to assume that the degree of passivation of the SiO2 surface by hydroxyl groups is an important controlling factor in the dissociation process. Our calculations of various slab settings, using dispersion-corrected density functional theory, support this assumption. We observe physisorption of the precursor molecule on a fully hydroxylated SiO2 surface (untreated surface) and chemisorption on a partially hydroxylated SiO2 surface (pretreated surface) with a spontaneous dissociation of the precursor molecule. In view of these calculations, we discuss the origin of this dissociation and the subsequent autocatalysis.
Author: | Kaliappan Muthukumar, Harald O. JeschkeORCiD, Roser ValentíORCiDGND, Evgeniya Begun, Johannes Schwenk, Fabrizio PorratiORCiD, Michael HuthORCiDGND |
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URN: | urn:nbn:de:hebis:30:3-277774 |
DOI: | https://doi.org/10.3762/bjnano.3.63 |
ISSN: | 2190-4286 |
ArXiv Id: | http://arxiv.org/abs/1205.4167 |
Parent Title (English): | Beilstein journal of nanotechnology |
Publisher: | Beilstein-Institut zur Förderung der Chemischen Wissenschaften |
Place of publication: | Frankfurt, M. |
Document Type: | Article |
Language: | English |
Year of Completion: | 2012 |
Date of first Publication: | 2012/07/25 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2012/12/13 |
Tag: | Co2(CO)8; EBID; FEBID; deposition; dissociation; precursor; radiation-induced nanostructures |
Volume: | 3 |
Page Number: | 10 |
First Page: | 546 |
Last Page: | 555 |
Note: | This is an Open Access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. |
HeBIS-PPN: | 450944298 |
Institutes: | Physik / Physik |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
6 Technik, Medizin, angewandte Wissenschaften / 62 Ingenieurwissenschaften / 620 Ingenieurwissenschaften und zugeordnete Tätigkeiten | |
Sammlungen: | Universitätspublikationen |
Licence (German): | Creative Commons - Namensnennung 2.0 |