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arXiv · 1205.1295

Desorption of n-alkanes from graphene: a van der Waals density functional study

Elisa Londero·Emma K. Karlson·Marcus Landahl·Dimitri Ostrovskii·Jonatan D. Rydberg·Elsebeth Schröder
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Abstract

A recent study of temperature programmed desorption (TPD) measurements of small n-alkanes (CNH2N+2) from C(0001) deposited on Pt(111) shows a linear relationship of the desorption energy with increasing n-alkane chain length. We here present a van der Waals density functional study of the desorption barrier energy of the ten smallest n-alkanes (N = 1 to 10) from graphene. We find linear scaling with N, including a nonzero intercept with the energy axis, i.e., an offset at the extrapolation to N = 0. This calculated offset is quantitatively similar to the results of the TPD measurements. From further calculations of the polyethylene polymer we offer a suggestion for the origin of the offset.

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Elisa Londero, Emma K. Karlson, Marcus Landahl, Dimitri Ostrovskii, Jonatan D. Rydberg, Elsebeth Schröder. 2012-05-07. Desorption of n-alkanes from graphene: a van der Waals density functional study. https://doi.org/10.1088/0953-8984%2F24%2F42%2F424212

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