Marine seaweed Sargassum wightii extract as a low-cost sensitizer for ZnO photoanode based dye-sensitized solar cell

The exploitation of marine seaweed (Sargassum wightii) extract as a low-cost sensitizer for a ZnO photoanode based solar cell is reported. The UV-vis absorbance spectrum of the Sargassum wightii (S. wightii) extract has exhibited three absorption peaks at 412.5, 610 and 659.5 nm in visible region of the solar spectrum. The pigment analysis has confirmed the presence of photosynthetic pigments such as chlorophylls, carotenoids and fucoxanthin. The photovoltaic performance of the S. wightii extract as a sensitizer in ZnO photoanode based solar cell is examined under simulated solar light irradiation. The solar cell sensitized with the S. wightii extract has delivered a short-circuit photocurrent density (J(sc)) of 203 mu A cm(-2), open-circuit photo-voltage (V-oc) of 0.33 V, maximum peak power (P-max) of 31.02 mu W, fill factor of 0.46 and an overall solar to electrical energy conversion efficiency (eta) of 0.07%. The sustainability of the solar cell is demonstrated through stability study. The overall results of this study suggest that the exploration of vast marine seaweed pigment resources and their use as sensitizer in solar cell would be a low-cost and environment friendly alternative to the expensive ruthenium metal complexes.