Sensitization of photocurrents in solid-state electrochemical cells using conducting polyprrole

摘要

The effect of small concentration of methylene blue on the photocurents were studied in solid-state photoelectrochemical cells fabricated using conducting polyrrole (Ppy) coated electrodes sandwiched with solid polymer electrolyte viz. Polyvinyl alcohol (PVA) with phosphoric acid. These exhibit excellent photo-response to visible light: photocurrent being 3 To 4 orders of magnitude greater than dark current depending on the concentration of the sensitizer. The current-voltage Characteristics in such cells reveal that the charge transport is mainly governed by the space charge effects and the Sensitization effects are due to lowering of potential barrier formed at the Ppy/PVA interface under photoexcitation.