In the heart of Kyiv, researchers are unlocking the secrets of an ancient, ubiquitous material that could revolutionize the way we harness solar energy. Melanin, the pigment that gives skin, hair, and eyes their color, is the subject of cutting-edge research led by Dr. Tetyana Obukhova at the National Technical University of Ukraine ‘Igor Sikorsky Kyiv Polytechnic Institute’. Her work, published in the journal Materials Research Express, translates to Materials Research Express in English, is shedding new light on melanin’s potential as a solar light absorber, with significant implications for the energy sector.
Melanin, it turns out, is not just a biological pigment but also a remarkable semiconductor. Obukhova and her team have been investigating the optical and electrical properties of thin melanin films, grown from water solutions of eumelanin extracted from edible plants. Their findings reveal that these films exhibit high absorption coefficients in the visible light range, making them highly efficient at capturing solar energy.
“The melanin films demonstrate high values of absorption coefficient exceeding 60,000 cm^-1 in the wavelength range of 460–500 nm,” Obukhova explains. This range corresponds to photon energies between about 2.70 and 2.48 eV, making melanin an excellent candidate for solar light absorbers.
But what sets melanin apart from other materials is its stability and unique composition. The films are transparent, low conductive polymers with stable electrical parameters over time. Moreover, they contain a significant amount of OH groups and sp^2 hybridized CH_n bonds, which influence the films’ optical and electrical properties. “The presence of sp^2 bonds may increase the conductivity due to the enhanced π-electron delocalization,” Obukhova notes.
So, how might this research shape future developments in the energy sector? The potential is immense. Melanin-based solar cells could be more efficient, stable, and environmentally friendly than current technologies. They could be integrated into windows, roofs, and even clothing, turning every surface into a potential energy generator. Moreover, the use of edible plants as a source of melanin opens up possibilities for sustainable, large-scale production.
Obukhova’s work is just the beginning. As we continue to explore the properties of melanin, we may find even more applications in the energy sector and beyond. From solar panels to energy storage devices, the future of energy technology could be as diverse and adaptable as the pigment that colors our world. The journey from biological pigment to energy revolution is an exciting one, and it’s happening right now in the labs of Kyiv.