Researchers at Oregon State University have developed a new photocatalyst that efficiently converts sunlight and water into clean hydrogen energy. The material, created by a team led by Kyriakos Stylianou, is based on metal organic frameworks (MOFs).
According to a news release, the photocatalyst enables the high-speed, high-efficiency production of hydrogen, used in fuel cells for cars as well as in the manufacture of many chemicals including ammonia, in the refining of metals and in making plastics.
The photocatalyst, called RTTA-1, is a MOF-derived metal oxide heterojunction combining ruthenium oxide and titanium oxide doped with sulfur and nitrogen. It demonstrates remarkable efficiency in splitting water into hydrogen when exposed to sunlight. In just one hour, one gram of RTTA-1 produced over 10,700 micromoles of hydrogen, with a quantum yield of 10%.
“The remarkable activity of RTTA-1 is because of the synergistic effects of the metal oxides’ properties and surface properties from the parent MOF that enhance electron transfer,” Stylianou said. “This study highlights the potential of MOF-derived metal oxide heterojunctions as photocatalysts for practical hydrogen production, contributing to the development of sustainable and efficient energy solutions.”
This process offers a cleaner alternative to the conventional methane-steam reforming method of hydrogen production. While current electrocatalytic processes for hydrogen production from water depend on renewable energy sources, photocatalysis harnesses solar energy directly, potentially making it more cost-effective.
Although ruthenium oxide is expensive, the minimal amount used in the catalyst makes it potentially viable for industrial applications if it demonstrates good stability and reproducibility.
