Can artificial photosynthesis lead to new, carbon-neutral fuels?
By Dr. Tim Sandle
EDITOR AT LARGE SCIENCE
DIGITAL JOURNAL
August 27, 2025
Without photosynthesis we wouldn’t have food because it converts energy from the sun into chemical energy for the food chains. Image by Tim Sandle
Scientists from the University of Basel, Switzerland, have created a plant-inspired molecule capable of storing four charges using sunlight. This is regarded as a key step toward achieving the long-sought-after artificial photosynthesis. As a complexity, the process of artificial photosynthesis requires multi-electron reactions.
Whereas past attempts have failed, this process works under conditions of dimmer light, edging technology closer to real-world solar fuel production. Under the influence of light, the molecule stores two positive and two negative charges at the same time.
The intermediate storage of multiple charges is a key prerequisite for converting sunlight into chemical energy. Under this condiiton, the charges can be used to drive reactions – for example, to split water into hydrogen and oxygen.
Photosynthesis
Plants use the energy of sunlight to convert carbon dioxide into energy-rich sugar molecules; this is the foundation of virtually all life. Animals and humans can “burn” the carbohydrates produced in this way again and use the energy stored within them. This once more produces carbon dioxide, closing out the cycle. Photosynthesis arose early in Earth’s history.
This process could also be the key to environmentally friendly fuels. For several years, scientists have been working to replicate natural photosynthesis by using sunlight to produce high-energy compounds. This includes so-termed ‘solar fuels’, such as hydrogen, methanol and synthetic petrol. If burned, such fuels would produce only as much carbon dioxide as needed to produce useful fuels. These would be carbon-neutral.
New molecule
The new molecule consists of five parts. These are linked in a series and each 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 pick up the electrons, which causes them to become negatively charged. In the middle, the chemists placed a component that captures sunlight and starts the reaction (electron transfer).
To generate the four charges, the researchers innovated photochemistry, in terms of taking a stepwise approach using two flashes of light. The first flash of light strikes the molecule and triggers a reaction in which a positive and a negative charge are generated. These charges travel outward to the opposite ends of the molecule. With the second flash of light, the same reaction occurs again, resulting in the molecule containing two positive and two negative charges.
The stepwise excitation makes it possible to use significantly dimmer light. This means moving closer to the intensity of sunlight. Earlier research required extremely strong laser light, some way from artificial photosynthesis.
The new findings from the study should help to improve understanding of the electron transfers that are central to artificial photosynthesis.
The research appears in the journal Nature Chemistry, titled “Photoinduced double charge accumulation in a molecular compound.”
August 27, 2025
Without photosynthesis we wouldn’t have food because it converts energy from the sun into chemical energy for the food chains. Image by Tim Sandle
Scientists from the University of Basel, Switzerland, have created a plant-inspired molecule capable of storing four charges using sunlight. This is regarded as a key step toward achieving the long-sought-after artificial photosynthesis. As a complexity, the process of artificial photosynthesis requires multi-electron reactions.
Whereas past attempts have failed, this process works under conditions of dimmer light, edging technology closer to real-world solar fuel production. Under the influence of light, the molecule stores two positive and two negative charges at the same time.
The intermediate storage of multiple charges is a key prerequisite for converting sunlight into chemical energy. Under this condiiton, the charges can be used to drive reactions – for example, to split water into hydrogen and oxygen.
Photosynthesis
Plants use the energy of sunlight to convert carbon dioxide into energy-rich sugar molecules; this is the foundation of virtually all life. Animals and humans can “burn” the carbohydrates produced in this way again and use the energy stored within them. This once more produces carbon dioxide, closing out the cycle. Photosynthesis arose early in Earth’s history.
This process could also be the key to environmentally friendly fuels. For several years, scientists have been working to replicate natural photosynthesis by using sunlight to produce high-energy compounds. This includes so-termed ‘solar fuels’, such as hydrogen, methanol and synthetic petrol. If burned, such fuels would produce only as much carbon dioxide as needed to produce useful fuels. These would be carbon-neutral.
New molecule
The new molecule consists of five parts. These are linked in a series and each 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 pick up the electrons, which causes them to become negatively charged. In the middle, the chemists placed a component that captures sunlight and starts the reaction (electron transfer).
To generate the four charges, the researchers innovated photochemistry, in terms of taking a stepwise approach using two flashes of light. The first flash of light strikes the molecule and triggers a reaction in which a positive and a negative charge are generated. These charges travel outward to the opposite ends of the molecule. With the second flash of light, the same reaction occurs again, resulting in the molecule containing two positive and two negative charges.
The stepwise excitation makes it possible to use significantly dimmer light. This means moving closer to the intensity of sunlight. Earlier research required extremely strong laser light, some way from artificial photosynthesis.
The new findings from the study should help to improve understanding of the electron transfers that are central to artificial photosynthesis.
The research appears in the journal Nature Chemistry, titled “Photoinduced double charge accumulation in a molecular compound.”
No comments:
Post a Comment