Researchers at Columbia University have developed a way to harness more power from singlet fission to increase the efficiency of solar cells, providing a tool to help push forward the development of next-generation devices.
All modern solar panels operate by the same process – one photon of light generates one exciton, said Luis Campos, an associate professor of chemistry and one of three principal investigators on the study. The exciton can then be converted into electric current. However, there are some molecules that can be implemented in solar cells that have the ability to generate two excitons from a single photon – a process called singlet fission. These solar cells form the basis for next-generation devices, which are still at infancy. One of the biggest challenges of working with such molecules, though, is that the two excitons “live” for very short periods of time (tens of nanoseconds), making it difficult to harvest them as a form of electricity.
In a study published by Nature Science this month and funded in part by the Office of Naval Research, Campos and colleagues designed organic molecules that can quickly generate two excitons that live much longer than the state-of-the-art systems, which leads to an amplification of electricity generated per photon that is absorbed by a solar cell. It is an advancement that can not only be used in next-generation solar energy production, but also in photocatalytic processes in chemistry, sensors, and imaging.
“Intramolecular singlet fission has been demonstrated by our group and others, but the resulting excitons were either generated very slowly, or they wouldn’t last very long,” Campos said. “This work is the first to show that singlet fission can rapidly generate two excitons that can live for a very long time. This opens the door to fundamentally study how these excitons behave as they sit on individual molecules, and also to understand how they can be efficiently put to work in devices that benefit from light-amplified signals.”
How big a deal is this for Nigeria?
Part of the reason a lot of people are still skeptical about going solar is that they fear that it may not be a sufficient source of energy for their usage. Most of these people have a lot of appliances and don’t want to compromise with more energy efficient appliances and practices. When this innovation finally hits the market, it could double the output of solar panels and make it an even more robust alternative for backup or off-grid energy supply. High-output solar panels would also significantly reduce the space required for solar installations.
Source: Science daily