Packing hydrogen in

A group of chemists led by Dr. John Ripmeester, Program Leader of the Materials Structure and Function Group at the Canadian National Research Council's

(NRC-SIMS), have developed a technique to pack twice as many hydrogen molecules into a gas hydrate framework than was previously possible.

Gas hydrates that contain hydrogen require pressures of 25 atmospheres and temperatures at 0 degrees Celsius to remain stable. In that state, the typical gas hydrate contains approximately 2% hydrogen per volume of hydrate.

"The target storage capacity is 5 to 8% hydrogen to make a useful fuel storage medium," said Dr. Ripmeester. "We made it up to 5%. We're not completely there, but we are approaching the standard."

Despite their minimal storage capacity, gas hydrates are an attractive hydrogen source for fuel cells. They are not explosive and require less refrigeration and pressure to store than liquid hydrogen, making them easier to transport. Hydrates are mostly water, an inexpensive alternative to most other hydrogen-containing chemicals.