2 research outputs found
Entropy Variation in the Two-dimensional Phase Transition of Anthracene Adsorbed at the Hg Electrode/Ethylene Glycol Solution Interface
The adsorption of anthracene (C14H10), at the mercury electrode/ethylene glycol (EG) solution interface, is characterized by a low and almost constant capacity (about 8 ÎźF cmâ2) region (capacitive âpitâ or âplateauâ) in capacity vs. potential curves, upon selection of suitable values of temperature, bulk concentration and applied potential values. This result is rationalized assuming the occurrence of a 2D phase transition between two distinct adsorbed phases: (i) a âdisorderedâ phase, characterized by a flat âparallelâ disposition of the aromatic moiety on the electrode surface (ii) an âorderedâ phase, characterized by a âperpendicularâ disposition of the aromatic moiety on the electrode surface. The experimental evidence is rationalized by considering the chemical potential as an explicit function of the âelectric field/adsorbed moleculeâ interaction. Such a modelistic approach enables the determination of the relevant standard entropy variation
Entropy Variation in the Two-dimensional Phase Transition of Anthracene Adsorbed at the Hg Electrode/Ethylene Glycol Solution Interface
The adsorption of anthracene (C14H10), at the mercury electrode/ethylene glycol (EG) solution interface, is characterized by a low and almost constant capacity (about 8 ÎźF cmâ2) region (capacitive âpitâ or âplateauâ) in capacity vs. potential curves, upon selection of suitable values of temperature, bulk concentration and applied potential values. This result is rationalized assuming the occurrence of a 2D phase transition between two distinct adsorbed phases: (i) a âdisorderedâ phase, characterized by a flat âparallelâ disposition of the aromatic moiety on the electrode surface (ii) an âorderedâ phase, characterized by a âperpendicularâ disposition of the aromatic moiety on the electrode surface. The experimental evidence is rationalized by considering the chemical potential as an explicit function of the âelectric field/adsorbed moleculeâ interaction. Such a modelistic approach enables the determination of the relevant standard entropy variation