Globally, the steady increase in 5% of energy per year has urged the need of alternative sources of renewable energy and has become a top challenge. The PV technology has become the most promising technology in harvesting the solar-energy. The use of natural pigments has become a viable alternative to expensive and rare Ruthenium dyes because of its low cost, easy attainability, abundance in supply of raw materials and no environment threat. In this paper, we investigate the performance of Dye Sensitized Solar Cells (DSSCs) based on natural dyes extracted from Indian medicinal plants. Herein, Cubebin and Betalain dyes are extracted from fresh Ocimum tenuiflorum and Piper nigrum. FT-IR, FT-Raman, Photoluminescence and UV–visible light absorption characteristics of the dyes are used to identify the characteristic peaks of the extracted dyes. Features of the electronic absorption spectrum in the visible and near-UV regions were assigned based on TD-DFT calculations. These dyes are used as photo sensitizer for fabrication of TiO2 photo-anode based dye sensitized solar cells (DSSCs). The photo-voltaic characteristics of the developed DSSCs are measured under simulated solar light. The solar to electric conversion efficiencies for the Cubebin and Betalain and mixed dye based solar cells are estimated as 0.39% and 0.38% respectively. The highest conversion efficiency for natural photo sensitizers based solar cell is attributed due to the absorption of wider range of solar spectrum.
