A new approach has improved the performance of organic solar cells, making them able to operate even in low light.

Researchers at the University of British Columbia (UBC) have found an inexpensive and sustainable way to make biogenic solar cells, photovoltaic units made up of substances obtained through genetic manipulation. The innovation, as indicated in the article published in Small magazine, is based on the use of bacteria, and more particularly E. coli, the microorganism that inhabits the intestines of most mammals. Scientists have redesigned these bacteria to increase the current density of these cell types. In this way, they were able to obtain cells with a much higher current density and work even in very low light conditions.

Until now, most attempts to produce biogenic solar cells have focused on extracting the natural dye used by bacteria for photosynthesis, an expensive and cumbersome process that involves the use of dangerous toxic components. The UBC researchers took a different approach: They left the dyes in the bacteria, modifying them to produce large amounts of lycopene, a strong photoactive pigment. They then coated the microorganisms with titanium dioxide (TiO2) nanoparticles, which act like semiconductors, applying the resulting mixture to a glass surface.


The team thus achieved a current density of 0.686 milliamps per square centimeter, significantly higher than the 0.362 milliamps obtained by other research in this field.

We have achieved the highest current density for a biogenic solar cell“Said Vikramaditya Yadav, professor of chemical and biological engineering at UBC.

These hybrid materials that we are developing can be produced economically and sustainably and, with sufficient optimization, can operate with efficiencies comparable to conventional solar cells.. “

The savings in detail are difficult to estimate, but Yadav says the process reduces the cost of producing the dyes to about a tenth of the current cost. Tests have shown that the new cells are able to function even in low light conditions.

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