A new material devised by Greek scientists could be the answer for safe and efficient hydrogen storage.
One of the major hurdles to using hydrogen as a fuel is an effective and convenient means of storing it – particularly for use in transportation. Scientists around the globe have explored myriad different materials in efforts to find one with potential.
Now a team from the University of Crete in Greece think that they may have come up with a viable option that almost meets US Department of Energy targets.
One of the options that scientists have explored is carbon nanotubes – tiny cylinders of carbon about 50,000 times thinner than a human hair. But George E. Froudakis and his team take this idea one stage further.
The scientists have designed a material consisting of sheets or ‘floors’ of graphene – layers of carbon just one atom thick – connected together by vertical columns of carbon nanotubes. The structure allows hydrogen to be stored in the gaps between the nanotube pillars and the graphene ‘floors’. They also add lithium ions to enhance its hydrogen storage capacity.
While they haven’t built the ‘pillared graphene’ structure yet, the scientists’ calculations indicate that it could store up to 41 g of hydrogen per litre, just short of the DOE target of 45 g per litre.
“Our material is capable of hosting a large number of hydrogen molecules without the aid of external pressure,” says Froudakis. “Thus the material [should be] safer for usage on automobile applications and will provide faster loading times than any other existing material.”
If the structure can be built and the predictions are correct, the new material could overcome one of the major drawbacks that has prevented hydrogen from being used extensively as a fuel for automotive applications, say the scientists.
For further information:
Dimitrakakis, G. K., Tylianakis, E., and Froudakis, G. E., Pillared Graphene: A New 3-D Network Nanostructure for Enhanced Hydrogen Storage. Nano Letters (2008), doi: 10.1021/nl801417
06 October 2008