Michigan professor: 'Hydrogen produced by our technology could be very cheap'

Scientists at the University of Michigan (UM) have found a way to increase the efficiency in converting water into hydrogen and oxygen to 9% through a new type of solar panel. 

According to a news release, the creation, which basically recreates an important step in natural photosynthesis, is about 10 times more efficient than previous experiments of its kind. The team of researchers believes their artificial photosynthesis devices will be far more efficient than the photosynthesis, which occurs naturally.

“We reduced the size of the semiconductor by more than 100 times compared to some semiconductors only working at low light intensity,” Peng Zhou, first author of the study and UM research fellow in electrical and computer engineering, said in the press release, “Hydrogen produced by our technology could be very cheap.”

The semiconductor can withstand concentrated light equal to 160 suns and thrives in high temperatures that are punishing to computer semiconductors. 

Humans currently produce hydrogen from the fossil fuel methane, which takes a large amount of fossil energy in the process, while plants harvest hydrogen atoms from water using sunlight. In recent years, hydrogen has become an attractive option as the push to reduce carbon emissions continues, the release noted. 

The team was able to come to its outstanding results thanks to two advances, which are the ability to concentrate light without destroying a semiconductor and using both the higher energy part of the solar spectrum to split water and the lower part of the spectrum to provide heat that encourages the reaction.

According to the news release, the catalyst is made of indium gallium nitride nanostructures. It captures the light and converts it into free electrons and holes.  

The outdoor version of the experiment, with less reliable sunlight and temperature, achieved 6.1% efficiency at turning the energy from the sun into hydrogen fuel. Indoors, however, the system achieved 9% efficiency. 

The team intends to further improve the efficiency and to achieve ultrahigh purity hydrogen that can be directly fed into fuel cells.