New catalysts designed as well as investigated yesteryear Tufts University School of Engineering researchers as well as collaborators from other academy as well as national laboratories convey the potential to greatly trim back processing costs inwards futurity fuels, such equally hydrogen. The catalysts are composed of a unique construction of unmarried golden atoms outflow yesteryear oxygen to several sodium or potassium atoms as well as supported on non-reactive silica materials. They demonstrate comparable activity as well as stability amongst catalysts comprising precious metallic nanoparticles on rare- globe as well as other reducible oxide supports when used inwards producing highly purified hydrogen. The work, which appears inwards the Nov 27, 2014, edition of Science Express, points to novel avenues for producing single-site supported golden catalysts that could make high-grade hydrogen for cleaner loose energy role inwards fuel-cell powered devices, including vehicles.
“In the facial expression upward of precious metals scarcity as well as exorbitant fuel-processing costs, these systems are promising inwards the search for sustainable global loose energy solutions,” says senior writer Maria Flytzani-Stephanopoulos, the Robert as well as Marcy Haber Endowed Professor inwards Energy Sustainability as well as professor inwards the Department of Chemical as well as Biological Engineering at Tufts.
Flytzani-Stephanopoulos’s question grouping has been active inwards designing catalysts requiring a lower sum of precious metals to generate high-grade hydrogen for role inwards fuel cells. The water-gas shift reaction, inwards which carbon monoxide is removed from the fuel gas current yesteryear reacting amongst H2O to make carbon dioxide as well as hydrogen, is a cardinal stride inwards the process. Catalysts, such equally metallic oxide supported precious metals similar platinum as well as gold, are used to lower the reaction temperature as well as increase the production of hydrogen.
The Tufts grouping was the commencement to demonstrate that atomically dispersed golden or platinum on supports, such equally cerium oxide, are the active sites for the water-gas shift reaction. Metal nanoparticles are “spectator species” for this reaction.
Flytzani-Stephanopoulos says the novel question suggests unmarried precious metallic atoms stabilized amongst alkali ions may hold upward the only of import catalyst sites for other catalytic reactions. “If the other particles are genuinely ‘spectator species’, they are thus unnecessary. Future catalyst production should as well as so focus on avoiding particle formation altogether as well as instead hold upward prepared exclusively amongst atomic dispersion on diverse supports,” says Flytzani-Stephanopoulos.
The only published question describes how unmarried golden atoms dispersed on non-reactive supports based on silica materials tin hold upward stabilized amongst alkali ions. As long equally the golden atoms, or cations, are stabilized inwards a single-site cast configuration, irrespective of the type of support, the precious metallic volition hold upward stable as well as operate for many hours at a arrive at of practical temperatures.
“This novel atomic-scale catalyst configuration achieves the maximum efficiency as well as utilization of the gold,” says Flytzani-Stephanopoulos, who directs the Tufts Nano Catalysis as well as Energy Laboratory. “Our run showed that these single-site golden cations were active for the low-temperature water-gas shift reaction as well as stable inwards functioning at temperatures equally high equally 200°C.”
“Armed amongst this novel understanding, practitioners volition hold upward able to pattern catalysts using only the necessary sum of the precious metals similar golden as well as platinum, dramatically cutting downwards the catalyst damage inwards fuels as well as chemicals production processes,” she adds.
Source: Tufts University