Rechargeable battery based on substituted LS polyanilines
Polo Nazionale Bioelettronica, Marciana,
(LI), Italy
El.B.A.
Foundation, Rome (Italy) and
Institute of Biophysics,
University of Genoa (Italy)
This is an abstract
for a poster to be presented at the
Fifth
Foresight Conference on Molecular Nanotechnology.
The full paper is available here.
Conducting polyaniline has been recently postulated as a
potential candidate for numerous electronic applications such as
electrochromic displays, rechargeable batteries, microelectronic
devices, biosensors, protection coating and chemical sensors. The
effect of substituent groups (-CH3, -OCH3
or -OC2H5 etc.) in monomer or polymeric
chain of polyanilines appears to enhance such potentiality, by
displaying at the same time a significant increase in electronic
localization with simultaneous decrease in conductivity and an
excellent solubility in a number of organic solvents [1]. The
solubility of polyanilines enables to assemble such conducting
polymers into ultrathin films at the molecular level with high
degree of order. Namely, very thin films of polyaniline (PANI)
[2], poly(o-anisidine) (POAS) [3,4] and poly(ethoxy aniline)
(PEOA) [5] have been engineered by either Langmuir-Blodgett (LB)
or Langmuir Shaefer (LS) techniques. It can be seen that the
effect of substituent plays a prominent role for the fabrication
of such ultra thin films.
Extensive analytical studies have been carried out on the
kinetics of Langmuir film formation; LS films of substituted
polyanilines. Langmuir isotherm of the PANI, poly(o-toluidine)
(POT), POAS, and PEOA were investigated at aqueous subphase of pH
1, where the doping during the monolayer formation appeared an
essential step for the high quality of Langmuir film. The area
per unit molecule was shown to increase with the increase in the
substituent groups. The deposited LS films of such polyanilines
were characterized by UV-visible, X-ray diffractometry, Brewster
microscopy, ellipsometry and cyclic voltammetry, respecctively.
While the conductivity of polyaniline films was shown to be
decreasing as a function of substituents in aniline monomer, the
surface investigated by scanning tunneling microscopy (STM)
showed an increase of the amorphosity as a function of
substituents in polyanilines LS films. In this communication, the
main objective is to report on the link existing between the
above findings and the charging/discharging properties of
substituted polyanilines LS films toward the optimal
manufacturing of a rechargeable battery based on this class of
conducting polymer.
References
[1] E.T.Kang, et al. Synth. Met. 48, 231 (1992).
[2] M.K.Ram, et al. J. Phys. Chem. 97, 11580 (1993).
[3] M.K.Ram, et al. Langmuir, in press (1997)
[4] S. Paddeu, et al. J. Phys. Chem., in press (1997)
[5] D. Goncalves, et al. Thin Solid Films. 243, 544 (1994)
*Corresponding Address:
Claudio Nicolini, Fondazione EL.B.A., Via Medaglie d'Oro 305 -
00136 Rome, Italy, ph: +39 6 35410728, fax: +39 6 35451637,
email: [email protected]
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