ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Thin mesoporous polyaniline films manifesting a water-promoted photovoltaic effect

Natalia Gospodinova, Elena Tomšík, and Julia Romanova

Leibnitz Institute of Polymers, Dresden e.V., Hohe Straße 6, 01069, Dresden, Germany

E-mail: gospodinova@imc.cas.cz

Abstract: Photovoltaic cells composed of thin mesoporous polyaniline films sandwiched between an indium-tin oxide anode and aluminium cathode have been fabricated. The cells show an increase in the photo-generated open-circuit voltage (V_oc) from 0.2 V to 0.6 V and stable-in-time V_oc generation following the addition of water containing highly hydrated ions, e.g. tap water.We explain the waterpromoted photo-voltaic effect by the polarity of the water environment. Theoretical calculations show that increasing the solvent polarity increases the energy of the electronic transition related to the measured V_oc. The stable-in-time V_oc generation could be explained by the increase in the lifetime of the excitons as well as by their more efficient dissociation in the interpenetrating network of polyaniline and water. The penetration of water into the mesoporous polyaniline films is promoted by the presence of highly hydrated ions.

Keywords: polyaniline – morphology – photovoltaics – water – density functional theory

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-012-0293-5

Chemical Papers 67 (8) 972–978 (2013)