Optimization of performance characteristics of a mixed dye based photogalvanic cell for efficient solar energy conversion and storage

Performance characteristics of photogalvanic cells containing mixed dye – brilliant green and celestine blue as photosensitizer with reducing agent EDTA have been experimentally examined. Photopotential of 636 mV and photocurrent of 93 μA are observed for the system. Power conversion efficiency of photogalvanic cell based on brilliant green+celestine blue–EDTA is estimated as 0.31% while the maximum power output of the cell is found to be 59.1 μW. Photogalvanic cell based on this mixed dye system may be used for 65 min in dark. This study shows that the solar energy conversion capability of a mixture of dyes in aqueous medium is controlled by dye–dye interaction, its photo-degradation and its susceptibility to photo-oxidation.

► Photogalvanic cell is a photo-electrochemical device to convert solar energy directly into electricity.
► It involves photo-chemical reactions which give rise to high energy products on excitation of molecules by photons.
► Dyes like brilliant green (BG) and celestine blue (CB) are considered effective photo-sensitizers.
► Mixed dye system is preferred to utilize a broader solar spectrum.
► Cell based on EDTA − BG + CB system gives better electrical output, conversion efficiency and storage capacity.