A research team at the University of Limerick that includes collaborators from around the World has discovered a new class of porous materials (called sorbents) which can trap and store volatile materials such as hydrogen and natural gas.
The team is led by Dr Varvara Nikolayenko, formerly of the Department of Chemical Sciences and UL’s Bernal Institute, now working at Bayer AG and Professor Michael Zaworotko, Bernal Chair of Crystal Engineering and Science Foundation of Ireland Research Professor at UL’s Bernal Institute.
Professor Zaworotko explained: ‘Traditional sorbents have interconnected holes and pores like a sponge. The new sorbents we have discovered are more like Swiss cheese in that they have empty space, but they are not interconnected by pores. Our new materials point towards an alternate approach to store such gases which is both less energy intensive and safe.’
One of the most significant findings was that the ‘Swiss cheese’ sorbent expands when it is exposed to gases with very little structural rearrangement and can thus captures increasingly large quantities of gas as pressure is increased.
Dr Nikolayenko said: ‘The changes in the sorbent are reversible so the gas can be easily removed, and the sorbent can be recycled for further use. It is counterintuitive to expect a sorbent which has no pores to have the ability to trap volatile gases. This raises the question of whether there are many more such sorbents that are hiding in plain sight.’
Any new way of storing hydrogen would have implications for the growing hydrogen-powered transport industry as the gas currently needs to be stored under high pressure or at -253°C
Last year, Professor Zaworotko and his team developed a new material that is capable of capturing small amounts of benzene from the air and using significantly less energy than existing materials, which could ‘revolutionise the search for clean air’.
Image: Alan Place/UL