Cambridge University scientists develop breakthrough in solar power using photosynthesis

Scientists successfully split water into hydrogen and oxygen in new, more efficient process

Scientists at the University of Cambridge have made what they claim is a significant step forward in developing new ways to harness solar power.

The breakthrough was made by successfully splitting water into hydrogen and oxygen using 'semi-artificial photosynthesis', a process done by altering the photosynthetic machinery in plants.

The new research, led by academics at the University's St John's College, used semi-artificial photosynthesis to explore new ways to produce and store solar energy. They used natural sunlight to convert water into hydrogen and oxygen using a mixture of biological components and man-made technologies.

Photosynthesis is the process by which plants convert sunlight into energy, and oxygen is produced as a by-product of this photosynthesis when the water absorbed by plants is "split".

Scientists deem this to be one of the most important reactions on the planet because it is the source of nearly all of the world's oxygen and, with this new research, the researchers found that hydrogen, which is produced when the water is split, could potentially be a green and unlimited source of renewable energy.

Their findings could, therefore, be used to revolutionise the systems used for renewable energy production, the researchers claim.

Detailing their research in a new paper, published in Nature Energy, the scientists outline how their platform can achieve unassisted solar-driven water-splitting, while also managing to absorb more solar light than natural photosynthesis.

Katarzyna Sokól, the first author of the paper and a PhD student at St John's College, said:

"Natural photosynthesis is not efficient because it has evolved merely to survive so it makes the bare minimum amount of energy needed - around one-to-two per cent of what it could potentially convert and store."

Artificial photosynthesis has been around for decades but has not yet been successfully used to create renewable energy because it relies on the use of catalysts, which are often expensive and toxic. This means it can't yet be used to scale up findings to an industrial level.

However, Sokól and the team of researchers improved on the amount of energy produced and stored, and also managed to reactivate a process in the algae that had been dormant for millennia.

"Hydrogenase is an enzyme present in algae that is capable of reducing protons into hydrogen," she explained.

"During evolution this process has been deactivated because it wasn't necessary for survival, but we successfully managed to bypass the inactivity to achieve the reaction we wanted - splitting water into hydrogen and oxygen."

Sokól hopes the findings will enable the development of new innovative model systems for solar energy conversion.