6533b872fe1ef96bd12d2d8c
RESEARCH PRODUCT
Mixed Grotthuss and Vehicle Transport Mechanism in Proton Conducting Polymers from Ab initio Molecular Dynamics Simulations
Thomas D. KühneDaniel SebastianiGuillermo A. Ludueñasubject
Conductive polymerchemistry.chemical_classificationMaterials scienceProtonGeneral Chemical EngineeringGeneral ChemistryPolymerThermal conductionAmorphous solidchemistry.chemical_compoundchemistryComputational chemistryChemical physicsYield (chemistry)NafionMaterials ChemistryMoleculedescription
We elucidate the microscopic mechanism of long-range proton conduction in poly[vinyl phosphonic acid] (PVPA), a highly promising proton conducting polymer. Using a steered ab initio molecular dynamics approach, we characterize the charge transport functionality of acid groups interacting with nonbulk water molecules intercalated in the polymer. Our results show that in PVPA, unlike in Nafion, water has a local vehicle/carrier function for excess protons. This function must however be combined with the Grotthuss-type conduction mechanism that is supplied by the acid groups in order to yield long-range charge transport. As an additional aspect, we find that contrary to common intuition, systems with disordered/amorphous morphology leave a considerably more pronounced functionality than well-ordered crystalline systems.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-02-20 | Chemistry of Materials |