Scale-dependent diffusion anisotropy in nanoporous silicon.
Kondrashova D, Lauerer A, Mehlhorn D, Jobic H, Feldhoff A, Thommes M, Chakraborty D, Gommes C, Zecevic J, De Jongh P, Bunde A, Kärger J, Valiullin R (2017)
Publication Type: Journal article, Original article
Subtype: other
Publication year: 2017
Journal
Publisher: Nature Publishing Group
Book Volume: 7
Pages Range: 40207
DOI: 10.1038/srep40207
Abstract
Nanoporous silicon produced by electrochem. etching of highly B-doped p-type silicon wafers can be prepd. with tubular pores imbedded in a silicon matrix. Such materials have found many technol. applications and provide a useful model system for studying phase transitions under confinement. This paper reports a joint exptl. and simulation study of diffusion in such materials, covering displacements from mol. dimensions up to tens of micrometers with carefully selected probe mols. In addn. to mass transfer through the channels, diffusion (at much smaller rates) is also found to occur in directions perpendicular to the channels, thus providing clear evidence of connectivity. With increasing displacements, propagation in both axial and transversal directions is progressively retarded, suggesting a scale-dependent, hierarchical distribution of transport resistances ("constrictions" in the channels) and of shortcuts (connecting "bridges") between adjacent channels. The exptl. evidence from these studies is confirmed by mol. dynamics (MD) simulation in the range of atomistic displacements and rationalized with a simple model of statistically distributed "constrictions" and "bridges" for displacements in the micrometer range via dynamic Monte Carlo (DMC) simulation. Both ranges are demonstrated to be mutually transferrable by DMC simulations based on the pore space topol. detd. by electron tomog. [on SciFinder(R)]
Authors with CRIS profile
Additional Organisation(s)
Involved external institutions
Gottfried Wilhelm Leibniz Universität Hannover
Germany (DE)
Universität Leipzig
Germany (DE)
National Center for Scientific Research / Centre national de la recherche scientifique (CNRS)
France (FR)
Universiteit Utrecht (UU) / Utrecht University
Netherlands (NL)
Justus-Liebig-Universität Gießen
Germany (DE)
IISER Indian Institute of Science Education and Research Mohali
India (IN)
Quantachrome Instruments
United States (USA) (US)
Germany (DE)
Universität Leipzig
Germany (DE)
National Center for Scientific Research / Centre national de la recherche scientifique (CNRS)
France (FR)
Universiteit Utrecht (UU) / Utrecht University
Netherlands (NL)
Justus-Liebig-Universität Gießen
Germany (DE)
IISER Indian Institute of Science Education and Research Mohali
India (IN)
Quantachrome Instruments
United States (USA) (US)
How to cite
APA:
Kondrashova, D., Lauerer, A., Mehlhorn, D., Jobic, H., Feldhoff, A., Thommes, M.,... Valiullin, R. (2017). Scale-dependent diffusion anisotropy in nanoporous silicon. Scientific Reports, 7, 40207. https://dx.doi.org/10.1038/srep40207
MLA:
Kondrashova, Daria, et al. "Scale-dependent diffusion anisotropy in nanoporous silicon." Scientific Reports 7 (2017): 40207.
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