What looks like a piece of plastic waste is floating on the River Cam in Cambridge, England. But it is a miniature solar-powered hydrogen factory,
Scientists around the world are looking for new ways to produce hydrogen and other gases that can be used as fuel without using fossil fuels. One of them is solar-to-fuel technology. Based on the example of plant photosynthesis, the energy of sunlight is used to split water and thus produce hydrogen gas. By reacting simultaneously with CO2, syngas can also be produced from hydrogen and carbon monoxide, which can then be further processed into methanol and other liquid fuels, for example.
The structure floating here on the river is a newly developed system that enables exactly this in the smallest of spaces and in a swimmable form. Virgil Andrei from the University of Cambridge and his colleagues attached two photoelectrodes and catalysts to a flexible, thin polymer layer and protected them with a special top layer.
The result is around 30 to 100 milligrams per square centimeter, light and thin modules that can float on the water. When sunlight falls on these floating modules, it triggers an electrochemical reaction that splits water and CO2. Depending on the catalyst, the system converts the molecules primarily into hydrogen or into syngas.
According to the researchers, their "artificial leaves" are as efficient as a real plant leaf in terms of this conversion. If confirmed, such ultra-lightweight, buoyant solar-to-fuel modules could open up new opportunities to use sunlight to produce "green" hydrogen and other clean fuels. The thin, flexible miniature reactors could be used as floating hydrogen or syngas factories on lakes, in ports or even at sea.