Molecular dynamics simulation of a polymer–inorganic interface

Abstract

The ever-present challenge of matching polymer electrolyte to electrode in making any type of electrochemical device is addressed herein. Since fundamental experimental data on the structural nature of the polymer–inorganic interface at the atomic level is scarce (not to say non-existent), molecular dynamics simulation can give the first suggestive insights into how an idealized interface — here between PEO and double-layered V 2O 5 gel – can behave. The model simulated here (at a nominal 400 K) comprises ca. 20 Å-thick slabs of PEO and 15 Å-thick V 2O 5 gel layers arranged to form an infinite sandwich-type structure. A number of clear trends emerge: dynamical motion in both PEO and V 2O 5 is significantly reduced in the interface region, where it is also clear that relatively stable local structural configurations develop. These appear to be controlled by interactions between the ether oxygens of the PEO and the VO bonds which form the surface of the V 2O 5. Experimental confirmation of such features is lacking.