The newly developed Metal Organic Framework has realised effective storing of hydrogen fuel with concentrations as high as 7.5 percent, writes Arun M Isloor.
In these days of fast depleting fossil fuels like petrol, diesel and coal, a cheaper and environmentally friendly hydrogen gas could be the right choice. And the imposing challenge is in finding ways to store large amounts of Hydrogen at the right temperature and pressure.
The U.S Department of Energy estimates that practical Hydrogen fuel will require concentrations of at least 6.5 percent. Very recently Chemists at UCLA and the University of Michigan have achieved the concentrations of 7.5 percent!
The findings which will be published in the Journal Of American Chemical Society by this month end (March), explains about Hydrogen fuel which powers not only vehicles, but also electronic devices. The research was carried out by Prof Omar Yaghi, faculty of UCLA-Chemistry along with Prof Adam and Dr Antek Wong-Foy.
The new material which Yaghi discovered for storing hydrogen gas at right temperature and pressure is called MOF (Metal Organic Framework), commonly pronounced as 'moffs' which are just like scaffolds made of linked rods that maximises the surface area. As they are composed of pores, they are also termed as crystal sponges. Yaghi and colleagues succeeded in storing the gases in the nano-scale openings. (Such gases are usually difficult to store and transport).
In a common man’s language, the process is like capturing water with sponges.
These MOFs can be made highly porous, to increase their storage capacity. One gram of MOF has the surface area of a football field! Yaghi’s laboratory so far has made more than 500 such frameworks, with wide variety of structures and properties.
According to Yaghi, who is a member of California nanosystems Institute, these frameworks can be made by cheaper ingredients like zinc oxide and terephthalate. Molecules can go in and out of them without any obstruction and they can make polymers inside the pores with well defined and predictable properties.
“Instead of battery, one would have a medium like this which stores hydrogen and releases it into fuel cells,” he adds.
In this case, he is concentrating hydrogen gas into a very small volume without using high pressure or very low temperature, so that enough gas can be stored for an automobile to run for 300-400 miles without refuelling!. When hydrogen undergoes combustion in a fuel cell, it produces only water as a byproduct.
The project was financially supported by the National Science Foundation of US, US Department of Energy & BASF (A German based MNC).