“Hydrogen sulfide emissions can result in hefty fines for industry, but remediation is also very expensive,” said Rice engineer, physicist and chemist Naomi Halas. “The phrase ‘game-changer’ is overused, but in this case, it applies. Implementing plasmonic photocatalysis should be far less expensive than traditional remediation, and it has the added potential of transforming a costly burden into an increasingly valuable commodity.”
As Rice University researchers explain, each hydrogen sulfide gas (H2S) molecule contains a pair of hydrogen atoms and one atom of sulfur. Each molecule of clean-burning hydrogen gas (H2) contains a pair of hydrogen atoms.
Halas’ team dotted the surface of silicon dioxide powder grains with tiny islands of gold. Each island was a gold nanoparticle about 10 billionths of a meter across that would interact strongly with a specific wavelength of visible light. These plasmonic reactions create “hot carriers,” short-lived, high-energy electrons that can drive catalysis.
In the study, Halas and co-authors used a laboratory setup and showed a bank of LED lights could produce hot carrier photocatalysis and efficiently convert H2S directly into H2 gas and sulfur.
The process is more efficient than the traditional catalytic technology refineries use to break down hydrogen sulfide, which requires multiple steps and, in some cases, high-intensity heating, according to Rice University.
The plasmonic hydrogen sulfide remediation technology has been licensed by Syzygy Plasmonics, a Houston-based startup company with more than 60 employees, whose co-founders include Halas and Nordlander.
