Scientists discover new method to convert sunlight into fuel

Researchers have successfully split water into hydrogen and oxygen by altering the photosynthetic machinery in plants as part of their quest to harness solar power.

Photosynthesis is the process where plants convert sunlight into energy, producing oxygen as by-product when the water absorbed by plants is ‘split’.

It is one of the most important reactions on the planet because it is the source of nearly all of the world’s oxygen.

While hydrogen, which is produced, when the water is split could potentially be a green and unlimited source of renewable energy.

The new study, led by academics at St John’s College, University of Cambridge, 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 manmade technologies.

The paper, published in Nature Energy, outlines how academics at the Reisner Laboratory in Cambridge developed their platform to achieve unassisted solar-driven water-splitting.

The Cambridge research is also part of the emerging field of semi-artificial photosynthesis, which aims to overcome the limitations of fully artificial photosynthesis by using enzymes to create the desired reaction.

First author at St John’s College, Katarzyna Sokó 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 it 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.

Sokó and the team of researchers not only improved on the amount of energy produced and stored, they managed to reactivate a process in the algae that has been dormant for millennia.

okó hopes the findings will enable new innovative model systems for solar energy conversion to be developed.