EXCHARGEHYD · The origin of excess charge at the water/hydrophobic interfaces

The main purpose of this proposal is the theoretical investigation of salt adsorption process at the interface of water/hydrophobic substrates taking into account impurities, dissolved gases using thermodynamically consistent force fields for ions by molecular dynamics methods. Most hydrophobic polymer materials without any functional and reactive surface groups develops a substantial negative charge at the interface of water-hydrophobic substrate. Source of this excess charge is not determined yet while the effect is enormous for electrically driven flows, in the context of electrical energy conversion, and it lies at the heart of many electrochemical and electrokinetic processes. Despite intensive theoretical and experimental efforts during past decades, this remarkable effect is still far from complete understanding. Molecular dynamics studies of water/hydrophobic substrate interfaces using atomistic force fields are challenging and can provide important information about structure and dynamics of the environment and shed light of interface phenomena. The proposed research aims to provide novel insight into structure and dynamics of water/vapor, water/hydrophobic substrate interfaces and provide a strong base for an investigations of ion transport through biochannels, and help elucidate the mechanisms by which these biochannels function.