Researchers at Oregon State University (OSU) have made headlines with their development of a new material capable of converting sunlight and water into clean energy.
Led by Kyriakos Stylianou from OSU’s College of Science, the team created a photocatalyst that promises high-speed and high-efficiency hydrogen production.
The key to OSU’s breakthrough lies in the use of metal organic frameworks (MOFs), which are crystalline, porous materials composed of metal ions and organic linker molecules. These MOFs feature nanosized pores and can be engineered to exhibit specific properties. The researchers utilized MOFs to derive a metal oxide heterojunction—a combination of two materials with complementary properties—to create a catalyst capable of splitting water into hydrogen when exposed to sunlight.
The catalyst, referred to as RTTA, combines MOF-derived ruthenium oxide and titanium oxide doped with sulfur and nitrogen. The team tested multiple variations of RTTA, ultimately identifying RTTA-1 as the most effective. RTTA-1, with the lowest ruthenium oxide content, demonstrated the fastest hydrogen production rate and a high quantum yield, producing over 10,700 micromoles of hydrogen per gram in just one hour.
RTTA-1’s impressive hydrogen production efficiency, utilizing 10% of incident photons for hydrogen generation, highlights its potential as a practical hydrogen production method. However, the use of ruthenium oxide, a costly material, raises questions about the economic viability of this technology on an industrial scale. While the minimal amount of ruthenium oxide used in the photocatalyst mitigates some cost concerns, the overall affordability of this approach remains a critical factor for widespread adoption.
Hydrogen production through photocatalysis is cleaner than traditional methods like methane-steam reforming, which generates significant carbon dioxide emissions. Despite the environmental advantages, the current cost disparity between green hydrogen and hydrogen produced from natural gas presents a significant hurdle. Methane-steam reforming produces hydrogen at approximately $1.50 per kilogram, whereas green hydrogen costs around $5 per kilogram.
The sustainability of hydrogen production via photocatalysis hinges on the use of renewable energy sources. For this technology to be competitive, the energy used in the catalytic process must be both renewable and affordable. Achieving cost parity with conventional hydrogen production methods is essential for market viability.
The research received funding from the College of Science, OSU’s Department of Chemistry, and donations from retired public school teachers and alumni Brian and Marilyn Kleiner. The project’s collaborative nature involved contributions from graduate students and faculty members, highlighting the interdisciplinary effort required to advance hydrogen production technologies.
