Considered a clean fuel - because when it burns in air it forms water - Hydrogen can be used to fuel motor vehicles, provide energy for homes and even power rockets and spaceships.
At the University of South Carolina, a graduate student, Xiaojing Sun, is using the Linkam CCR1000 stage to look at the phase change of a complex hydride LiBH4, which could potentially be used as a Hydrogen (H2) store. There are several possible ways of storing H2: under high pressure, using cryogenics and within chemical compounds that act as a reversible store. Any method used needs to be safe, reliable and have an acceptable energy density.
LiBH4 is a complex hydride and a chemical molecule that can store H2. When it melts it breaks down into several constituents: B, Li2B12H12, LiH and H2. The scientists are studying the phase transitions of LiBH4 and attempting to identify the crystallographic structures with Raman spectroscopy. They aim to further understand these decomposition mechanisms as the products and intermediates are not well understood.
Xiaojing Sun says: “The cell and temperature controller are very well designed and working well.” She has found that when the reactant decomposes to form H2 around 400°C, and is cooled fully, infused with hydrogen, and heated again, the amount of H2 released for this second cycle is significantly decreased. She hopes to learn what chemical changes occur during the increasing temperature and then may introduce some other metallic element to the reactant to achieve a better recycle.
As scientists gain a better understanding of LiBH4 and other complex hydrides, they move closer to the eventuality of hydrogen as a fuel, and a cleaner future for us all.
By Caroline Feltham