The impedance response of an electrochemical cell able to convert sunlight into electrical power is analyzed and discussed. Light conversion is due to a photosynthetic system known as reaction center, which is the core of photosynthesis in several living beings. Under illumination, an abrupt transformation drives the cell electrical response from insulator to conductor and a photocurrent is observed. The impedance spectrum shows a peculiar shape which significantly modifies after the protein activation. It has been analyzed by means of a graphical/analytical/numerical procedure. Some impedance graphical representations are indicated as the most appropriate to suggest the design of an equivalent electrical circuit. Then, the analytical expression of this circuit is formulated and used to set-up a custom Phyton code useful for fitting experimental data. Finally, an appropriate normalization procedure is proposed, which validates data in dark and light and can be useful as a fast screening of measurements.
A Biological-based Photo Electrochemical Cell: Modelling the Impedance Spectra
Alfinito, Eleonora
Primo
Membro del Collaboration Group
;Milano, FrancescoMembro del Collaboration Group
;Beccaria, MatteoMembro del Collaboration Group
;CATALDO, RosellaMembro del Collaboration Group
;Giotta, LiviaMembro del Collaboration Group
;Trotta, MassimoMembro del Collaboration Group
;Guascito, Maria RacheleUltimo
Membro del Collaboration Group
2020-01-01
Abstract
The impedance response of an electrochemical cell able to convert sunlight into electrical power is analyzed and discussed. Light conversion is due to a photosynthetic system known as reaction center, which is the core of photosynthesis in several living beings. Under illumination, an abrupt transformation drives the cell electrical response from insulator to conductor and a photocurrent is observed. The impedance spectrum shows a peculiar shape which significantly modifies after the protein activation. It has been analyzed by means of a graphical/analytical/numerical procedure. Some impedance graphical representations are indicated as the most appropriate to suggest the design of an equivalent electrical circuit. Then, the analytical expression of this circuit is formulated and used to set-up a custom Phyton code useful for fitting experimental data. Finally, an appropriate normalization procedure is proposed, which validates data in dark and light and can be useful as a fast screening of measurements.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
