Explosion-harnessing nanocapsules could jump-start hydrogen economy

Filed in archive Energy on June 27, 2006

Nanoscale capsules that stabilize extremely dangerous compounds normally prone to igniting or exploding can safely generate more than enough hydrogen gas to beat U.S. Department of Energy goals for hydrogen production for 2015 just by dropping them in water, according to a United Press International story picked up by Physorg.com:

The capsules are safe and easy to handle, and after they react the only byproducts are environmentally friendly, such as sand or sodium silicate, "which is the main ingredient in toothpaste," explained Michael Lefenfeld, New York-based SiGNa Chemistry's president and chief executive officer.

Sodium, potassium and other alkali metals are potentially extraordinarily useful elements because they are highly chemically reactive. However, this also makes them dangerously volatile.

"If you drop sodium in water, you'll see it dance as a fireball on the surface. If you drop rubidium in water, it's like a hand grenade. And cesium is like a depth charge. It's why people have avoided using them," Lefenfeld said. He and his colleagues developed a method to enclose nanoparticles of alkali metals in porous capsules made of ceramics such as silica or alumina. These capsules soak up the loose electrons that make the alkali metals so violently unstable, while at the same time maintaining their reactivity. "If the alkali metals were not in nanoclusters, you could not achieve stabilization," Lefenfeld said.

One exciting possibility for these capsules is generating hydrogen gas for vehicles in the future. Combining hydrogen gas with oxygen results in energy and water, and none of the dirty mix of toxins and global warming gases burning gasoline spews forth. The cleanliness of hydrogen is in large part why government and industry support for hydrogen vehicles has reached into the billions of dollars.

Scientists worldwide are experimenting with cost effective and convenient sources of hydrogen. The U.S. Department of Energy requirement for hydrogen production for 2015 is a material that can generate 8 weight percent hydrogen, "so if you put in 100 grams of a material, you're supposed to get eight grams of hydrogen back," Lefenfeld said. "Our materials currently can get up to 9 weight percent hydrogen, exceeding the 2015 requirement, with the potential of achieving 13 or 14 weight percent hydrogen which is nearly double the DoE 2015 requirement." (image GKSS)