Low-Cost, Eco-friendly Solar Cells Made Possible Using Kumkum Dye

A team of researchers has developed low-cost, environment-friendly solar cells by employing an off-the-shelf dye used to make kumkum in India.

A team of researchers at the Indian Institute of Technology Hyderabad (IIT-H) have developed low-cost, environment-friendly solar cells by employing an off-the-shelf dye used to make kumkum or vermilion in India.

According to the research published in the Solar Energy journal, the dye-sensitised solar cell (DSSC) is based on New Fuchsin (NF) dye with aqueous electrolyte and platinum-free counter electrodes.

The most familiar solar cells today are made up of silicon and can be seen in the various overhead panels and other places noted Professor Sai Santosh Kumar Raavi from Department of Physics, IIT-Hyderabad. However, this technology is limited by huge fabrication costs as silicon processing is very expensive and involves very high temperature methods that leave a large carbon footprint, Raavi, who led the project, said. 

In order to get around the limitations of using silicon, the team started working on solar cells based on organic materials, which were supposedly inexpensive and easy to fabricate. 

However, there were many drawbacks impeding the organic photovoltaic technology as organics (plastic) are less robust. Many dye molecules developed for efficient DSSC devices are very expensive and toxic upon ingestion. Also, most DSSC devices tend to get degraded as they come in contact with atmospheric moisture, Raavi added. 

In their latest work, Raavi’s team consisting of researchers from Department of Physics and Chemistry (IIT Hyderabad), ARCHEM (University of Hyderabad), NIT Kurukshetra and IFSC-USP, Brazil, employed a very cheap magenta-dye called New Fuchsin, which is used to make kumkum or vermillion when grounded with turmeric. 

“It’s cheap, non-toxic and is soluble in water and importantly does not degrade in the presence of water,” Raavi said. DSSC is a third-generation thin-film organic molecule-based energy conversion device, and it takes its inspiration from nature, almost mimicking the primary process of photosynthesis in plants.

This technology using NF dye, researchers said, could be used to build integrating photovoltaics. NF is an inexpensive dye available off-shelf in most supermarkets in India, and in its purest form costs USD two per gram. 

By the choice of cell components during the fabrication, a low-cost eco-friendly DSSC based on NF dye with aqueous electrolyte and platinum-free counter electrodes is achieved, Raavi added.