1. Energy Theme Dr Allan Walton SCIRA - Senior Research Fellow
Hydrogen Storage Materials and Hydrogen Processing of Materials

2. Solid State Hydrogen Storage
Schlapbach and Züttel, Nature, 15 Nov 2001 (modified)
Mg2NiH4
LaNi5H6
H2 (liquid)
H2 (200 bar)
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.

3. Overview of Solid State Hydrogen Storage Materials
Zeolites
Activated carbons
MOFs
Bridged carbon foam spillover material
Adsorbents
Absorbents
Bridged IRMOF 8
LaNi5
MgH2
LiBH4
LiNH2/MgH2
AlH3 Pd
Ca(BH4)2
Temperature for significant hydrogen release oC
Observed H2 weight fraction (%)
Polymers of Intrinsic Microporosity (PIMS)
-200
-100
100
200
300
400 2 4 6 8 10 12 14
Carbon nanotubes
Mg2Ni
US DOE system target 2010

4. 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

5. Melt Spinning of Magnesium Alloys
Production of rapidly solidified amorphous and metastable ribbons in high vacuum or inert gas
Thickness: 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

6. Melt Spinning Facility in Metallurgy and Materials at the University of Birmingham
Automatic sample positioning
Inert sample loading
Inert sample transfer

7. Confocal Laser Microscopy
Graph showing optical transparency vs pressure for a 65nm Pd film.
Sample cell
77K – 873K, 10-6mBar – 100 bar H2
Pd film
valves
Pressure transducer
Anti-vibration table

8. 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.

9. 65nm Pd hydride film on exposure to air