It's said to be the biggest stumbling block for using hydrogen fuel in cars - The gas tank.

What we take for granted in our present generation of cars is becoming the Gordian knot for proponents of hydrogen as a fuel. The reason lies in the characteristics of hydrogen and our present developmental handicaps. Hydrogen gas is notoriously difficult to store. Though three times as energy dense than petrol, when liquefied it has just one-fourth the energy as the same volume of petrol. And that too involves high pressures and super cooling. The latest prototype vehicles can travel only up to 450 kilometers (280 miles) on a full tank. Therefore, scientists are focusing on ways to efficiently store more amounts of hydrogen within the same confined areas of cars. This advancement alone could give a huge fillip to hydrogen fuel development.

Five years ago, The US Department of Energy set forth a challenge for development of new age materials that could store 6% of their weight in hydrogen. Now, material scientists in Greece may have come up with a solution. The solution - carbon nanoscrolls.

A team from the University of Crete led by George Froudakis last year had used carbon nanoscrolls to hold 3.31% of their weight in hydrogen. Now, going further forward they have designed a similar material that can theoretically hold twice as much. The new design comprises sheets of graphene – atom-thick carbon sheets – separated by 1.2-nanometre-tall carbon nanotube pillars. What is further appealing is that simulations prove that the new material adsorbs 6.1% of its weight in hydrogen at room temperature and pressure.


George Froudakis is satisfied with the material and believes that what the simulations showed in theory could easily be transferred to reality as their previous material last year had behaved as predicted.

Their team is not the only one on the firmament though, as The US Department of Energy's challenge has invigorated the scientific community. Like Gábor Laurenczy at the Swiss Federal Institute of Technology in Lausanne, Switzerland. He believes that formic acid (found naturally as the poison in ant stings) is the best potential hydrogen storage material. His research showed that although formic acid can only store only 4.4% of its weight as hydrogen, in terms of volume, one liter of formic acid holds 53 grams of hydrogen. By comparison, liter of Froudakis' carbon nanomaterial holds only 41 grams.

George Froudakis opines that the formic acid angle is also a worthy one but with one crucial difference from his own. Making formic acid requires temperatures of around 100 °C, while his material can store large quantities of hydrogen at room temperature.

As research labs around the world get charged up over hydrogen, don't be surprised of your children's car becomes 'new age' not only in terms of era but also in terms of radical technology.

Source: NewScientist.com
Image: Wikimedia