Metal Hydrides as Hydrogen Carriers

By Prof. Marcello Baricco, Department of Chemistry and NIS, University of Turin, Turin, Italy.

Prof. Marcello Baricco
Department of Chemistry and NIS, University of Turin, Turin, Italy

Renewable energies, such as photovoltaic and wind power, are characterized by intermittent production, so their storage is necessary for an efficient management. Among several solutions proposed, the use of hydrogen as an energy carrier is under investigation. Compared to batteries, hydrogen allows storing larger amounts of energy in small volumes, over long-time, i.e. no self-discharge issues, with low environmental impact [1]. Hydrogen can be absorbed in the form of a metallic hydride under mild conditions, i.e. close to room temperatures and atmospheric pressure. This solution ensures a safe storage and reduces the volume required for storing even large quantities of hydrogen. Solid state hydrogen storage based on hydrides has been investigated in recent years, with the goal to improve hydrogen gravimetric density and to match thermodynamic requirements necessary for dehydrogenation reactions with an equilibrium close to ambient conditions.
In this presentation, recent results obtained on metl hydrides as energy carriers will be outlined. Samples are synthetized by arc melting or ball milling. The structure is determined by XRD, coupled with Rietveld refinement. The thermal behaviour is analysed by HP-DSC. The hydrogen sorption is characterized by PCT, MS and TGA. An assessment of thermodynamic properties of various systems has been obtained by the CALPHAD approach. Results of hydrogen sorption and assessments of thermodynamic properties for metal hydrides (e.g. MgH2 [2]) and intermetallic compounds (e.g. La(Ni,Al)5H7 [3]), will be reported. On the basis of hydrogen sorption properties, applications of solid state hydrogen tanks coupled with PEM fuel cells will be shown [4].
Disordered solid solutions with a high configurational entropy Sconf >1.5 R, where R is the gas constant, are commonly defined High Entropy Alloys (HEA). Lattice distortion in bcc HEP allows hydrogen to accommodate not only in tetrahedral interstitial sites, but even in the octahedral ones, increasing the hydrogen gravimetric density. An in-house developed method [5], based on maps related to atomic radius, electronegativity and electronic concentration, has been used to identify HEA to be used as hydrogen carriers. As an example, hydrogen sorption properties of the TiV0.6Cr0.3Zr0.3NbMo alloy [6], which consists of a solid solution with cubic centered body structure plus a fraction of intermetallic compounds, will be reported.
Hydrogen storage at large scale remains a challenge and the HyCARE project [7], supported by the European Fuel Cells and Hydrogen Joint Undertaking [8] plans to address it. The project involves the production of about 5 tons of a metal alloy, which will fill special containers for large-scale stationary hydrogen storage. The thermal management of the plant will take place through an innovative approach, making use of phase change materials, significantly increasing the efficiency of the process. The amount of stored hydrogen will be around 50 kg, which will represent the highest quantity ever stored in Europe with this technique. The concept and the research behind the project will be presented and discussed.

[1] N.Belmonte, V.Girgenti, P.Florian, C.Peano, C.Luetto, P.Rizzi, M. Baricco, Int. J. Hydrogen Energy, 41 (2016) 21427–21438.
[2] M.W.Rahman, A.Castellero, S.Enzo, S.Livraghi, E.Giamello, M.Baricco, J. All. Comp. 509S (2011) S438–S443.
[3] E.R.Pinatel, M.Palumbo, F.Massimino, P.Rizzi, M.Baricco, Intermetallics, 62 (2015) 7-16.
[4] P.Rizzi, E.Pinatel, C.Luetto, P.Florian, A.Graizzaro, S.Gagliano, M.Baricco, J. All. Comp. 645S (2015) S338-S342
[5] M.G.Poletti, L.Battezzati, Acta Mater 75 (2014) 297-306.
[6] U.Spaliviero, M.G.Poletti, L.Battezzati, M.Baricco, submitted to La Metallurgia Italiana

M. Baricco1, J. Barale1, V. Gulino1, U. Spaliviero1, E. Dematteis1,2, N. Berti1, G. Fiore1, A. Castellero1, P. Rizzi1, L. Battezzati1

(1) Department of Chemistry and NIS, University of Turin, Turin, Italy
(2) Université Paris Est, ICMPE (UMR7182), CNRS, UPEC, F-94320 Thiais, France


Marcello BARICCO was born in Torino (1958). He obtained the PhD in Chemistry in 1987. He works for the Department of Chemistry of the University of Torino since 1990. He reached the position of Associate Professor in 1998 and, since 2004, he was full professor in Metallurgy at the University of Torino. From 2015, teaching position changed into Materials Science and Technology. He’s now Deputy Rector of the University of Turin.

He was supervisor of about 65 degree thesis and of 18 Ph.D. thesis. He has been responsible for the University of Torino in several research projects with European and Italian research institutions and industrial partners (e.g. FLYHY, COSY, BOR4STORE, ECOSTORE). He coordinated the SSH2S European project on hydrogen storage and now he coordinates the EU H2020 project HyCARE, financed by FCH JU. He is an expert in the Task 40 of the IEA-HIA and member of Scientific Committee of FCH-JU. He is coordinator of SP7 on Hydrogen Storage of JP on Fuel Cells and Hydrogen of EERA.

The research activity is mainly based on Materials Science and Technology. The scientific contributions have been presented in about 300 publications in peer refereed national and international journals with over 3400 citations. A list of published papers can be found at ORCID or ResearchID.