Nanoconfinement Effect on n-Alkane Flow

Nanoconfinement induces change of microscopic structures of n-alkanes, which, in turn, alters their dynamics. We study a fundamental question of nanoscale n-alkane flow through in-depth theoretical analysis of relating microscopic structures to macroscopic dynamic properties. We show that the velocity profile and corresponding flux are governed by the interfacial resistance from first-layer n-alkanes near a nanopore wall and the viscous resistance from other n-alkanes in nanopores. We find that n-alkane flow through nanopores is a function of nanopore wall energy, nanopore diameter, and n-alkane properties, which allows a wide range of enhancement factors, spanning over 4 orders of magnitude reported in the literature, to be quantitatively rationalized. Most importantly, we demonstrate that there is huge potential in manipulating n-alkane flow by tuning nanopore wall composition and nanopore size. We propose a theoretical framework of modeling the flow of macromolecule fluids beyond n-alkanes at the nanos...