Understanding the structural and conductive properties of glyonic liquids with computational methods.

Abstract

Rhamnolipid is a well-known class of biosurfactant that can be biologically produced by Pseudomonas species. It has been widely studied for its properties such as biodegradability and non-toxicity. Ionic liquids (ILs) are salts in liquid state with melting points below 100°C. ILs have impressive physicochemical properties including non-volatility, non-flammability, air and water stability, and good electrical conductivity, and therefore are famous materials nowadays. An innovative sugar-based ionic liquid (IL), glyonic liquid (GL), is created by a combination of rhamnolipid as anion and an amine-based cation. GL is valued as an environmentally friendly material with low cost, good tunability and superionic proton conductivity. Also, the experiments show that the conductivity is highly related to the water fraction in GLs. To investigate the underlying reason for the high conductivity, we utilize classical molecular dynamics (MD) simulation to determine conformations and atomic level structures in a series of GLs systems. 3D networks composed of interacting polar atoms are found inside the GLs and are qualitative predictors of actual conductivities. We also use an MS-EVB model to simulate the proton transport process among the whole system to investigate the conductive mechanism in the mixture of GL and water. The results will be presented in detail.