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Dr Allan Walton SCIRA - Senior Research Fellow Energy Theme Hydrogen Storage Materials and Hydrogen Processing of Materials. LaNi 5 H 6. H 2 (liquid). Mg 2 NiH 4. H 2 (200 bar). Schlapbach and Züttel, Nature , 15 Nov 2001 (modified). Solid State Hydrogen Storage. 4 kg H 2.
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Dr Allan Walton SCIRA - Senior Research Fellow Energy Theme Hydrogen Storage Materials and Hydrogen Processing of Materials
LaNi5H6 H2 (liquid) Mg2NiH4 H2 (200 bar) Schlapbach and Züttel, Nature, 15 Nov 2001 (modified) Solid State Hydrogen Storage 4 kg H2 • At STP 1 mole of gas occupies 22.4 litres. • 1 kg H2 occupies ~11 m3 at STP. • 4-5kg of H2 would be required for a 400km car journey. • The hydrogen storage problem is essentially one of gas compression. • In solid state hydrogen storage, H2 is captured within the crystal structure of a material such as LaNi5. • Solid state materials can offer a safe, low pressure solution for hydrogen storage. • However a material has not yet been found which offers the correct wt% H2 at the correct pressure, temperature and price to meet the requirements for an automotive application.
Observed H2 weight fraction (%) Adsorbents Absorbents 14 US DOE system target 2010 LiBH4 12 Ca(BH4)2 10 AlH3 8 Bridged carbon foam spillover material MgH2 MOFs LiNH2/MgH2 6 Activated carbons 4 Bridged IRMOF 8 Polymers of Intrinsic Microporosity (PIMS) Mg2Ni 2 Zeolites LaNi5 Pd Carbon nanotubes 400 -200 -100 0 100 200 300 Temperature for significant hydrogen release oC Overview of Solid State Hydrogen Storage Materials
Equipment in the Hydrogen Materials Laboratory • 3 Gravimetric balance systems • 2 Volumetric sieverts systems • XRD with 10/100 bar gas cells and gas dosing system • Dispersive Raman spectrometer with gas cells and cryostat • Membrane testing facility • 3 mass spectrometers • High Pressure reaction vessels >700bar H2 • Hydrogen processing furnaces • Resistivity measurements • Melt spinner • Magnetron sputtering system with inert sample transfer • 3 gloveboxes • Flowing gas measurements • Reactive planetary and freezer milling • Confocal laser microscope with gas cells Bruker D8- XRD Gas reaction cell 10bar and 100 bar H2 Dispersive Raman Spectrometer Gas reaction cell 1bar/100bar H2
Melt Spinning of Magnesium Alloys • Production of rapidly solidified amorphous and metastable ribbons in high vacuum or inert gas • Thickness: 20-60 µm, 10mm • Sample size 5 – 10 grams • Cooling rates 105 – 106 K/sec • Wheel surface velocity 60m/sec • 5kW induction heater Slit nozzle Boron Nitride furnace tube
Melt Spinning Facility in Metallurgy and Materials at the University of Birmingham Automatic sample positioning Inert sample loading Inert sample transfer
Confocal Laser Microscopy Pd film Sample cell 77K – 873K, 10-6mBar – 100 bar H2 Graph showing optical transparency vs pressure for a 65nm Pd film. valves Pressure transducer Anti-vibration table
Confocal Laser Microscopy 3-D map of a 65nm Pd film deposited onto glass . Fully de-hydrided in air 9th cycle 3-D map of a 65nm Pd film deposited onto glass . Fully Hydrided 10th cycle at 1 bar Y.Pivak, R.Gremaud, K.Gross, M. Gonsalez-Silveira, A.Walton, H.Schreuders, B.Dam and R.Griessen. ‘Effect of the film substrate on the thermodynamic properties of the PdHx studied by hydrogenography’, submitted to the Scripta Materialia August 2008.
