The U.S. Department of Energy is funding a group of University of Rochester chemists to determine how to increase the output and lower the cost of current light-driven hydrogen-production systems. Hydrogen’s desirability comes from the fact it can be converted into electric energy and produces no carbon emissions.
This work builds upon and innovates previous ideas of energy science – namely that sunlight should be used to provide clean, carbon-free energy for anything that requires electricity. However, a major shortfall of the hydrogen findings is that hydrogen production is not always durable.
Although still at the basic research state, U.S. DOE scientists surmounted the problem by adding nanocrystals. Organic molecules used to capture light in photocatalytic systems only last a few hours, a day at most. Nanocrystals, however, can last up to 2 weeks.
Professor of chemistry Richard Eisenberg spent over 20 years studying solar energy systems. Over the course of his study, he found his systems generated 10,000 turnovers of hydrogen atoms being formed without having to replace any components. But the nanocrystals, which are far more efficient, generated turnovers in excess of 600,000.
Traditional photocatalytic systems have a definite disadvantage since they use expensive metals. Instead of using these precious metals, scientists recommend using metals more plentifully found on the Earth. They also stressed the need for these metals to be less toxic and cheaper. The cost difference between metals can be staggering. For instance, platinum sells for $24,000 per pound while nickel sells for $8 per pound.
Although a considerable amount of study is still needed, researchers are looking toward the future when they will be able to commercially implement their findings. The pharmaceutical and fertilizer industries, at the very least, would certainly benefit. The next step is to closely evaluate the nature of the nanocrystal and to determine if they will work even more efficiently if they are enclosed in shells.