Policy / Systems / Technology

April 12, 2018


Japanese Researchers Achieve World's First Production of Hydrogen from Water and Visible Sunlight

Keywords: Environmental Technology Renewable Energy 

Image by Hans.

With permission from Smart Japan, a news site providing the latest information on electricity conservation, storage and generation, we have translated here an article on the results of research on hydrogen production using visible light, originally published on June 1, 2017.

"The production of hydrogen from sunlight and water, if achieved, will make the transition from our present society built on fossil fuels to one based on hydrogen a feasible reality."

A research group led by Prof. Tetsuro Majima of the Institute of Scientific and Industrial Research at Osaka University announced in May 2017 that the photocatalyst they had developed with black phosphorus shows efficient hydrogen formation from water under both visible and near-infrared light. Their finding is the first in the world.

Conventional photocatalysts suffer from a low water-to-hydrogen conversion efficiency because they use ultraviolet light, which accounts for only three to four percent of the solar spectrum.

The study group has created ultrathin sheets composed of black phosphorous layers, which feature strong light absorption in the near-infrared as well as ultraviolet and visible light ranges, combined with lanthanum titanate layers. The sheets were then synthesized with nanometer-sized gold nanoparticles that can also absorb visible light.

In the resulting composite, both the black phosphorous and gold nanoparticles work as photosensitizers, the former responding to visible and near-infrared light, and the latter responding to visible light. In addition, they revealed that the excited electrons move to the lanthamum titanate, leading to efficient hydrogen production from water by proton reduction.

The use of their newly developed composite of black phosphorous, gold nanoparticles, and titanate lanthamum as a photocatalyst, the researchers commented, has made it possible to produce hydrogen from water and broadband sunlight, an innovation they expect will contribute significantly to solving environmental issues.

Source: Smart Japan (in Japanese)