Jackie Ying picks up a small vial of white powder. She shakes it, and the tiny particles swirl gracefully around like minuscule snow flakes.
The container holds roughly a gram – one-28th of an ounce – of the powdery substance. But that represents 100 square meters of surface area, or about one quarter the area of a basketball court.
Why so large? These are nanocrystals, each less than a thousandth of a hair’s breadth across, and their flat configurations and extraordinary numbers account for that amazing amount of surface. It also helps explain why they promise an exciting new era in low-polluting, high-efficiency energy production.
One key to their effectiveness is the fact that natural gas can be burned leaner – that is, with low fuel-to-air ratios — if aided by a catalyst that chemically boosts the combustion rate. (Ying’s catalyst is called barium hexaaluminate.) If the combustion improvement’s sufficient, emissions can be cut sharply.
“With our catalyst, you have no nitrogen oxides emissions from natural gas combustion,” notes Ying. “That’s because it lets you do things under very lean conditions, which means at lower temperatures. And the fuel combusts completely, so there are no unburned hydrocarbons.”
When used in a natural gas power or industrial plant, her nanocrystals thus promise to eliminate key pollutants linked with smog and acid rain. But creating a catalyst that can work in a real power plant took some doing.
In such plants, natural gas is burned in combustors linked to turbines. A plant may have a dozen or more combustors arranged around a turbine. Each contains a flame whose peak temperatures are around 2,500 degrees F.
So catalysts need to be tough. Ying’s nanocrystals, created in a special medium called a reverse microemulsion, are up to the task — but only because of a huge amount of experimentation. “We knew where we wanted to go,” says Ying, “but it took us three years to get there.”
Ying’s working with a European firm that plans to commercialize her nanocrystals. Meanwhile, she and her co-workers are also exploring innovative fuel cells — devices that produce electricity through the clean-burning of hydrogen and other fuels.
Though the work’s not as advanced, it probably wouldn’t be wise to bet against the group’s succeeding there as well — and a telling observation from Ying suggests one of the reasons. “The most amazing thing about this place is the students,” she says. “They’re very creative, and they’re not afraid of obstacles. They just go do it.”