Organic radical breakthrough can cause a revolution in the efficiency of solar energy
In a historical discovery, researchers from the University of Cambridge have identified a new way for organic molecules to harvest and generate electricity – possibly define the materials used in the next generation of sun technology.
The study shows that a specially designed organic semiconductor, known as P3TTM, can replicate a physical phenomenon that was previously only observed in inorganic metal oxides. This finding unites principles of both organic chemistry and condensed matter and offers a simpler, lighter and more affordable route to solar energy generation.
P3TTM is a spin-radical organic molecule that contains a single unpaired electron in the core. Developed by collaboration between the synthetic chemical group of professor Hugo Bronstein and the semiconductor Physics team of professor Sir Richard Friend, the material was initially designed for use in organic LEDs. New research published in Nature Materials, however, has discovered a hidden characteristic: when they are closely informed, P3TTM molecules show electronic interactions that are comparable to those in a Mott-Hubbard isolator.
“In most organic materials there are electrons in pairs and remain insulated,” explains Biwen Li from the Cavendish Laboratory. “In P3TTM connected non -purified electrons on each other and alternately up and down. When light touches the material, one of these electrons jumps to his neighbor and generates positive and negative loads that can be extracted as electrical current.”
If configured as a solar cell, a thin P3TTM film achieved an almost perfect efficiency of cargo collection – which means that almost every photon of light was converted into usable electricity. In contrast to traditional organic solar cells that require two materials to transfer electrons and holes, P3TTM can generate internal charge separation, driven by the intrinsic electronic structure that is governed by the physics of the MOTT hubbard.
Dr. Petri Murto designed molecular structures that refine the energy balance between molecules, making it possible to make efficient cargo separation. This concept with one material solar cells can drastically reduce production complexity and costs and at the same time improve performance.
The discovery also has symbolic weight. Senior author Professor Sir Richard Friend studied under Sir Nevill Mott, whose groundbreaking theories about electron interaction support this new breakthrough. “It feels like you’re coming around a circle,” said friend. “To see the ideas of MOTT realized in a modern organic system that can turn light into electricity, is really special.”
Professor Hugo Bronstein added: “We not only improve old designs. We write a new chapter in the textbook, which shows that organic materials can generate completely on their own.”
Research report:Intrinsic Intermolecular Photo -Induced Charging Separation With Organic Radical Semi -conductors
