The Project
This project is focused on the search for innovative materials to realize high capacity storage cells characterized by quick release times, suitable for practical applications. Among the solutions proposed and studied up to now, the storage as chemical energy by means of hydrogen will be addressed here.
The combustion reaction between hydrogen and oxygen gives an amount of energy for fuel unit mass three times higher than that of gasoline. Unfortunately, under standard conditions, hydrogen is a low density gas and it should be used in the liquid state to obtain its volumetric energy density comparable with that of the fossil fuels. Liquid H2 must be stored at -243 °C at ambient pressure in very expensive cryogenic containers, and this constraint makes the solution hardly practicable, especially for on-board uses.
The most efficient, cheap and safe way to store hydrogen, as testified by the last decade literature, is in solid form, i.e. “captured” in solid materials able to release the fuel with suitable rates under controlled pressure and temperature conditions. In this frame, a light (low molecular mass), cheap and safe material able to capture and release hydrogen in a reversible way and with satisfying kinetics (minutes) at ambient pressure and temperatures in the range between -20 °C and + 85 °C is required, in order to couple the hydrogen tank with a proton exchange membrane fuel cell for power production. Although the former expectations of the use of hydrogen for on-board applications at the moment are weakened, mainly because of the longer times needed by the basic research with respect to the expected ones, more confidence is growing for the use of hydrogen storage for stationary applications, thanks to the potentiality of the combination of hydrogen with renewable energies and co-generation.
