Photoelectrode Uses Sunlight to Turn Water Into Hydrogen: Study

A team of South Korean researchers has developed, for the first time, a new type of multi-layered photoelectrode that boosts the ability of splitting water through sunlight to produce hydrogen.

The photoelectrode, inspired by the way plants convert sunlight into energy, is capable of absorbing visible light from the sun, and then using it to split water molecules (H2O) into hydrogen and oxygen.

This photoelectrode takes the form of 2D hybrid metal-dielectric structure, which mainly consists of three layers of gold film, ultrathin TiO2 layer and gold nanoparticles.

The team reported that this promising photoelectrode shows high light absorption of about 90 percent in the absorption spectrum (380-700 nm) of pure water, as well as significant enhancement in photo-catalytic applications.

"This simple system may serve as an efficient platform for solar energy conversion, utilising the whole ultraviolet-visible range of solar spectrum based on two-dimensional plasmonic photoelectrodes," explained professor Jeong Min Baik from School of Materials Science and Engineering, UNIST.

Moreover, according to professor Baik, this photoelectrode uses approximately 95 percent of the visible spectrum of sunlight which makes up a substantial portion (40 percent) of full sunlight.

"The developed technology is expected to improve hydrogen production efficiency," he added in a paper appeared in the journal Nano Energy.