Molecular dynamics simulation of mass transfer characteristics of DMSO at the hexane/water interface in the presence of amphiphilic Janus nanoparticles

Abstract

Janus nanoparticles (JNPs) have drawn significant attention due to their unique surfaces with dual character. Herein, molecular dynamics simulation was conducted to investigate the molecular transfer characteristics across the hexane/water interface with amphiphilic JNPs, to elucidate the interfacial mass transfer enhancement mechanisms. The results manifested that the enhancement by JNPs first increases and then decreases with the rise of alkyl chain length, which is up to the biggest improvement under the C4H9 alkyl chain (JNPs-4). The enhancement can be ascribed to the competitive balance between solute diffusion behaviors and molecule interaction energy. The self-diffusion coefficient of solute and the interaction between the solute and oil phases decreases, while the interaction between the solute and water phases increases with the rise of alky chain length. Moreover, maximum enhancement can be obtained by 5 vol% concentration JNPs-4 with 13.4 Å particle diameter, in which the mass transfer resistance is reduced by 36.8%.