Study of the Phase States of Water Close to Nafion Interface
Bunkin NF1*, Ignatiev PS2, Kozlov VA1, Shkirin AV1, Zakharov SD3 and Zinchenko AA4
1A.M. Prokhorov General Physics Institute, Moscow, Vavilova 38, 119991 Russia
2Amphora Labs Co. Ltd, Moscow, 5th Magistralnaya 11, 123557 Russia
3P.N. Lebedev Physical Institute, Moscow, Leninskiy prospekt 53, 119991 Russia
4Donetsk National University, Shchorsa 46, Donetsk 83050, Ukraine
*Correspondence E-mail: nbunkin@kapella.gpi.ru
Key Words: Nafion, Exclusion Zone, Photonic Crystal, Refractive Index, Modulation Interference Microscopy
Received February 8th, 2013; Accepted March 1st, 2013; Published March 8th, 2013; Available online March 15th, 2013
Abstract
Experimental measurements of electrostatic potential and the bulk concentration of bisulfite anions in water close to Nafion (a proton – exchange membrane) interface have revealed jump – like changes of these characteristics at a distance of approximately 150 µm from the interface. Furthermore, the temperature behavior of the bisulfite anion concentration exhibits a sort of hysteresis loop, which can be regarded as a manifestation of multi-stability in the system. Additionally, it is experimentally shown that in the vicinity of Nafion interface the refractive index of water grows approximately by a factor of 1.1 as compared with the value in bulk water. The obtained results can be interpreted as evidence of the formation of a new phase in water adjacent to Nafion interface.