Scientists have found a new way to turn sunlight into fuel

Plants use the energy of sunlight to convert CO₂ in energy -rich sugar molecules. This process is called photosynthesis and is the basis of almost all life: animals and humans can “burn” the carbohydrates produced in this way again and use the energy stored in them. This once again produces carbon dioxide, closing the cycle.

This model can also be the key to environmental fuels, as researchers work to imitate natural photosynthesis and the use of sunlight to produce high -energy compounds: sun fuels such as hydrogen, methanol and synthetic gasoline. If burned, they would only produce as much carbon dioxide as necessary for fuel production. In other words, they would be carbon.

Molecule with a special structure

In the scientific journal Natural chemistryProfessor Oliver Wenger and his doctoral student Matis Bryandlin are already reporting an important intermediate step towards achieving this vision for artificial photosynthesis: they have developed a special molecule that can store four charging at a slight radiation – two positive and two negative ones.

Intermediate storage of multiple charges is an important prerequisite for converting sunlight into chemical energy: charges can be used to drive reactions – for example, to divide hydrogen water and oxygen.

The molecule consists of five parts, which are connected in a series and each of them performs a specific task. One side of the molecule has two parts that release electrons and are positively charged in the process. Two on the other side, they lift the electrons, which causes them to load negatively. In the middle, chemists placed a component that captures the sunlight and begins the reaction (transfer of an electron).

Two steps using light

In order to generate the four charges, the researchers took a gradual approach using two lightning lights. The first lightning of light hits the molecule and triggers a reaction that generates a positive and negative charge. These fees travel outside to the opposite ends of the molecule. With the second flash of light, the same reaction appears so that the molecule then contains two positive and two negative charges.

Works in low light

“This step excitation makes it possible to use significantly greater light. As a result, we are already moving near the intensity of sunlight,” explains Brändlin. More studies require an extremely strong laser light, which was far from the vision of artificial photosynthesis. “In addition, charges into the molecule remain stable enough to be used for additional chemical reactions.”

Given the new molecule, it has not yet created a functioning artificial photosynthesis system. “But we have identified and implemented an important piece of puzzle,” says Oliver Wenger. New discoveries from the study help to improve our understanding of electronic transfers that are central to artificial photosynthesis. “We hope that this will help us to contribute to new prospects for a sustainable energy future,” Wenger says.