The Mixing Behavior of Alkanes Adsorbed on Hexagonal Boron Nitride

DOI: 10.1021/acs.jpcc.6b07701

Authors: Matt Forster (Diamond Light Source) , Julia E. Parker (Diamond Light Source) , Akira Inaba (Research Center for Structural Thermodynamics Graduate School of Science, Osaka University) , Claire A. Murray (Diamond Light Source) , Nicholas A. Strange (Department of Chemistry, University of Tennessee) , John Z. Larese (University of Tennessee) , Thomas Arnold (Diamond Light Source)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: The Journal Of Physical Chemistry C

State: Published (Approved)
Published: October 2016
Diamond Proposal Number(s): 8994

Abstract: In this work we report the mixing behavior of a series of normal-alkanes adsorbed on the surface of hexagonal boron nitride (h-BN) using X-ray powder diffraction. We have investigated a range of simple binary mixtures which are indicative of a rich phase behavior with examples of complete mixing, partial mixing and phase separation. On graphite surfaces, the mixing behavior is strongly influenced by the structure of the pure components; the odd-even effect seen in the pure structures, which favors either a “herringbone” or “parallel” structure, influences the miscibility of alkanes within the monolayer. On h-BN a more complex phase behavior is observed with partial mixing or phase separation depending upon the exact composition of the monolayer. In particular, we see improved miscibility for certain mixtures containing n-decane which we associate with the fact that pure n-decane has been observed with both herringbone and parallel structures on h-BN. This difference between these two very similar substrates is a sensitive indicator of the subtle interplay between surface-molecule and molecule-molecule interactions that govern the phase behavior of these systems.

Subject Areas: Chemistry, Physics


Instruments: I11-High Resolution Powder Diffraction

Documents:
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