Researchers have uncovered the mechanism behind exciton fission in crystalline pentacene, a process that could enhance the efficiency of photovoltaic technology—converting light to electricity—by up to one-third. Unlike conventional solar cells, which transfer energy from a photon to a single electron, pentacene has the ability to convert one photon into two electrons, offering significant potential for high-efficiency solar energy applications. A team from the Fritz Haber Institute, the Technical University of Berlin, and Julius-Maximilians-Universität Würzburg has captured this photon-to-electricity conversion on an ultrafast time scale using advanced spectroscopy techniques.
Their findings clarify a longstanding debate regarding whether a photon excites two electrons simultaneously or if energy is first shared between a single excited electron and another. The researchers’ ability to visualize electron dynamics and their orbital patterns allowed them to confirm that one electron is excited directly, leading to the doubling mechanism. Understanding exciton fission is critical for integrating this process into silicon solar cells, ultimately paving the way for more efficient third-generation solar cells, which could significantly contribute to the future of sustainable energy amid rising investments in solar power technology.
