Scientists at IIT Roorkee used naturally occurring pigment in the Indian summer fruit Jamun to create more efficient and inexpensive solar cells.
The researchers used the pigment as an inexpensive photosensitiser for Dye Sensitised Solar Cells (DSSCs) or Gratzel cells. The study was published in the Journal of Photovoltaics.
What are Gratzel Cells?
These are thin film solar cells composed of a layer of dye molecules that absorb sunlight, a porous layer of titanium dioxide (TiO2) coated photoanode, an electrolyte for regenerating the dye and a cathode.
All these components together form a sandwich-like structure with the dye molecule (photosensitizer) playing a significant role due to its visible light absorbing ability.
• According to lead researcher and Assistant Professor Soumitra Satapathi, the dark colour of jamun and abundance of Jamun trees in the IIT campus clicked the idea that it might come of use as a dye in the typical Dye Sensitised Solar Cells (DSSC).
• The dye was extracted from Jamun using ethanol.
• The researchers also used fresh plums and black currant along with mixed berry juices that contain pigments that give characteristic colour to Jamun.
• The mixture was then centrifuged and decanted.
• The extracted coloured pigment, anthocyanin was then used as a sensitiser.
Satapathi further stated that natural pigments are more cost-effective in comparison to regular Ruthenium-based pigments and scientists are working to improve the efficiency. He added that their lab has been actively engaged in producing low-cost high-efficiency solar cells.
The research team, which includes Nipun Sawhney and Anubhav Raghav, is optimistic that they would be able to replicate the process for mass production of the solar cells.
This effort is in line with the search undertaken by researchers across the world to find an alternate energy to relieve pressure off fossil fuels, especially during the wake of rising concern of global warming.