Synthesis and development of novel sensitizer from spirulina pigment with silver doped TiO2 nano particles for bio-sensitized solar cells

Abstract

Pycocyanin pigment of spirulina (blue green algae) was used as photosentizer for the fabrication of Bio sensitized solar cells (BSSC). The pigment was extracted in different solvents such as water, Ethanol and Acetone and pure and “Ag (3 and 5 wt%)” doped TiO2 nanoparticles were prepared by facile sol-gel technique in order to fabricate BSSC. The structural, morphological, optical properties and Electrochemical impedance analysis of the prepared thin films were studied by powder X-ray diffraction, Field Emission Scanning Electron Microscopic (FE-SEM), Transmission Electron Microscopic technique (TEM), UV–Vis spectroscopy and current voltage characteristics respectively. The main observation from this research work is reduction of energy band gap values due to doped “Ag” ion which may allow the delayed recombination rate and enhance the photovoltaic conversion efficiency of around 1.2% when compared to that of pure TiO2 nanoparticles (0.74%) with N719 dye as 6.15. The photocurrent density - photo voltage (J-V) characteristics of fabricated BSSC via Pycocyanine pigments under various solvents adsorbed condition on nanocrystalline pure TiO2 and Ag doped TiO2 film electrodes were carried out. The pigments in association with water solution shows the short-circuit photocurrent density J(sc) of around 3.0 mA/cm2 and the open-circuit photo voltage (Voc) 0.75 V, under an illumination intensity of 40 mW/cm2 respectively. With the above observations, the research work claims that “Ag” doped TiO2 nanoparticles may be a promising candidate for future BSSC applications.