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Updated: Jul 16, 2026

Surface Properties of Synthesized Nanoporous Carbon and Silica Matrices
Published on: March 27, 2019
Preferred orientations and stability of medium length n-alkanes solidified in mesoporous silicon
A Henschel1, T Hofmann, P Huber
1Technische Physik, Universität des Saarlandes, D-66041 Saarbrücken, Germany.
Abstract:
The n-alkanes C(16)H(34), C(17)H(36), C(19)H(40), and C(25)H(52) have been imbibed and solidified in mesoporous, crystalline silicon with a mean pore diameter of 10 nm. The structures and phase sequences have been determined by x-ray diffractometry. Apart from a reduction and the hysteresis of the melting-freezing transition, we find a set of six discrete orientation states ("domains") of the confined alkane crystals with respect to the lattice of the silicon host. The growth process responsible for the domain selection is interpreted as a nanoscale version of the Bridgman technique known from single-crystal growth. Oxidation of the pore walls leads to extrusion of the hydrocarbons upon crystallization, whereas the solidified n-alkanes investigated in nonoxidized, porous silicon are thermodynamically stable.
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