Scientists at the Carnegie Institution have found that using a high pressure can create a very unique material for storing hydrogen. The discovery opens the door to a whole new way of addressing the problem of hydrogen storage.
Researchers have found that xenon, a noble gas that normally is not reactive, combines with molecular hydrogen (H2) under pressure to form a compound previously unknown.
Experiments carried out during this investigation represent the first time these elements have been combined to form a stable compound. The discovery reveals a new family of materials that could promote new technologies for use and handling of and deliverry hydrogen.
Xenon has some puzzling properties, including its usefulness as an anesthetic, its ability to preserve biological tissues, and its role in certain lighting.
The elements change its configuration when subjected to pressure, relatively similar to how passengers are accommodated in an elevator as it fills. Maddury Somayazulu and his team underwent a series of high pressure xenon gas mixtures and hydrogen in a diamond anvil cell.
At about 41,000 times the pressure at sea level (1 atmosphere), the atoms were arranged in a lattice structure dominated by hydrogen, but interspersed with layers of pairs of loosely bound xenon. When the researchers increased the pressure, like tuning a radio, the distances between pairs of xenon changed, the gap shrank to those observed in xenon heavy metal.
The researchers visualized the compound at different pressures using X-ray diffraction, Raman and infrared spectroscopy. When looking at the structure of xenon, they realized that the interaction of xenon with the surrounding hydrogen was responsible for the unusual stability and continuous change in the xenon-xenon distances as the pressure was adjusted from 41,000 to 255 000 atmospheres.
