6533b7cefe1ef96bd12572af

RESEARCH PRODUCT

Fast proton conduction in hydrogen bonded microheterogeneous systems: Bis(2-ethylhexyl)phosphoric acid/N-methyl formamide liquid mixtures

Angela RuggirelloMarco PassarelloPietro CalandraVincenzo Turco Liveri

subject

chemistry.chemical_classificationFormamideHydrogen bondAnalytical chemistryInfrared spectroscopyFast proton conduction systems Microheterogeneous liquid mixtures Bis(2-ethylhexyl)phosphoric acid N-methyl formamidePercolation thresholdSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsBiomaterialschemistry.chemical_compoundColloid and Surface ChemistrychemistryX-ray crystallographyFourier transform infrared spectroscopyPhosphoric acidAlkylSettore CHIM/02 - Chimica Fisica

description

Structural and dynamical properties of bis(2-ethylhexyl)phosphoric acid (HDEHP)/N-methyl formamide (NMF) liquid mixtures in the whole composition range have been investigated by Fourier Transform Infrared spectroscopy (FT-IR), X-rays Diffraction (XRD), and AC complex impedance spectroscopy. Driven by hydrogen bond interactions among HDEHP PO(4)H group and NMF CO and NH groups, and also by steric effects among the HDEHP alkyl chains, the system microstructure is mainly characterized by the coexistence of spatially separated hydrophilic and hydrophobic nanodomains showing local organization and short-range order. The evolution of this structural feature with system composition has been highlighted by FT-IR and XRD. On the other hand, the thermally activated proton mobility within these hydrophilic domains, as pointed out by AC complex impedance measurements, emphasizes the occurrence of a percolating behaviour characterized by percolation threshold at zero. Due to fast proton conduction across the interconnected network formed by the polar groups, some samples showed very high room-temperature conductivity up to 10(-3) S cm(-1).

yearjournalcountryeditionlanguage
2009-09-21Journal of Colloid and Interface Science
https://doi.org/10.1016/j.jcis.2009.11.021