Light to Electrical Energy Conversion in Photosynthetic Bacteria Cells and Cell Fragments Located between Semiconducting and Metal Electrodes

Arkadiusz Ptak and Danuta Frackowiak

Institute of Physics, Poznan University of Technology, Piotrowo 3, 60-965 Poznan, Poland.
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Photopotential action spectra as well kinetics of their generation and decay for green bacteria Prosthecochloris aestuarii cells and cell fragments were measured. The sample was located between two transparent electrodes, both semiconducting or one semiconducting and second one - metallic.

In the photopotential action spectrum the maximum at 747 nm responsible for the bacteriochlorophyll c oligomers absorption is absent. It shows that bacteriochlorophyll c molecules located in chlorosome oligomers are not taking part in the photopotential generation. The photopotential amplitudes increased with the sample pheophytinization. The samples exhibit the light gradient effect it means the change of the sign of the photopotential with the change of the side of illumination of the electrochemical cell.