Professor Allan Walton BSc, PhD

Dr Allan Walton

School of Metallurgy and Materials
Professor of Critical and Magnetic Materials
Co-Director of the Birmingham Centre for Strategic Elements and Critical Materials

Contact details

School of Metallurgy and Materials
University of Birmingham
B15 2TT

Professor Allan Walton has expertise in processing of permanent magnetic materials, solid state hydrogen storage materials, hydrogen processing of materials, coating technologies, hydrogen purification membranes and recycling of rare earth materials.  Allan is Professor of Critical and Magnetic Materials and is the ex-chair of the UK Magnetics Society.

He has published over 35 papers in scientific journals and has contributed to 4 patents held by the University of Birmingham.


  • PhD on Corrosion Protection for Rare Earth Permanent Magnets
  • BSc in Materials Science


Professor Allan Walton qualified with a BSc in Materials Science at the University of Birmingham in 1997.  He went on to study a PhD on the corrosion protection of Neodymium Iron Boron Magnets (qualified 2002) where he helped develop a zinc alloy coating process called Low Pressure Pack Sublimation which was patented by the University.  After becoming a research associate on corrosion studies for NdFeB permanent magnets he was employed as a research fellow studying solid state hydrogen storage materials at the University of Birmingham.

Allan has worked on five multi-disciplinary research projects including:
- 2001-2003 EU Framework 5 grant (FUCHSIA – Fuel Cells and Hydrogen Stores for Integration into Automobiles).
- 2003-2005 Carbon Trust R&D project (The Safe Efficient and Economic Large Scale Storage of Hydrogen).
- 2005-2006 NERC project (A whole System Approach for Analyzing Bio-Energy Demand and Supply).
- 2006-2009 EU Framework 6 Project (NESSHY – Novel Efficient Solid Storage for Hydrogen).

Professor Walton built and managed the hydrogen laboratories within Metallurgy and Materials installing over 30 pieces of equipment, much of which is bespoke.  The hydrogen labs are now one of the leading facilities for the synthesis and characterization of hydrogen storage materials in the UK and are known as a centre of excellence worldwide.  He has investigated a large range of potential hydrogen storage materials including carbon nanotubes, activated carbons, zeolites, metal organic frameworks, porous polymers, metal hydrides, magnesium-based materials (including melt spun material and high velocity ball milled) and complex hydrides.

In 2009, Allan began working as a Senior Science City Research Fellow.  His research was focused in two main areas – solid state hydrogen storage materials and permanent magnetic materials.  He was heavily involved in research into recycling of rare earth materials.  This research involves the use of hydrogen to extract rare earth magnets from scrap devices and re-processing of that material into new magnets.

In 2011, he took over as the head of the Magnetic Materials Research Group.  The MMG now has over £2.4 million in multi-disciplinary research projects on sustainable manufacturing routes for permanent magnets.  In recent years Allan has been tackling the shortages in the supply of rare earth materials; developing new lean processing routes for permanent magnets and novel recycling processes which have led to 3 international patent applications.

Professor Walton works closely with both the Hydrogen Materials Group run by Professor David Book at the University of Birmingham and the minerals processing group headed by Professor Neil Rowson.



  • 1st Year – Magnetic & Electronic Materials
  • 2nd Year – Functional & Ceramic Materials
  • 3rd Year – Advance Electronic Materials


  • MRes course – Materials for Sustainable Energy Technologies; lectures on porous materials for hydrogen storage and purification.
  • MSET/MEng Course – Materials for Sustainable Environmental Technologies; lectures on recycling of NdFeB magnets.

Postgraduate supervision

  • Microporous materials for hydrogen storage– Steven Paul Tedds, PhD
  • Melt-spun Mg-Ti-Ni alloys for hydrogen storage materials – Xiaodong Yi, PhD
  • In-situ hydrogen decrepitation of NdFB –Jonathan Meakin, MRes
  • Optimisation of HDDR processing parameters of sintered NdFeB magnets – Richard Sheridan, PhD
  • The effect of microstructure and composition on HDDR processing of scrap magnets – Alec Durrant, MRes
  • The processing and characterisation of recycled NdFeB-type sintered magnets – Malik Degri, PhD


Rare Earth Magnet Research


  • REProMag - EU FP7 Project
  • MagDrive - EU FP7 Project
  • EREAN - EU FP7 Marie-Curie Training Network
  • REMANENCE - EU FP7 Project
  • Strip Casting of NdFeB - Commercial Project
  • Characterisation & Production of SmCo - Commercial Project


  • The use of hydrogen decrepitation to extract NdFeB magnets form electronic assemblies
  • In-situ removal of magnets from large magnetic assemblies using hydrogen
  • Corrosion protection for NdFeB magnets
  • Investigation of electrical conductivity in magnetic materials

Hydrogen Storage Research

  • Melt spinning of magnesium based alloys
  • Assessment of porous polymers for hydrogen storage
  • Assessment of metal organic frameworks for hydrogen storage
  • The use of 3-D laser confocal microscopy to visualise hydrogen interactions in-situ.
  • Catalysed nanocrystalline MgH2 for hydrogen storage
  • Hydrogen storage properties of zeolitic materials
  • Production of multi layered Mg-Pd thin films
  • Assessment of “hydrogen spillover” on porous materials
  • Assessment of the hydrogen storage properties for carbon nanotubes, activated carbons, carbon soots and templated carbons.
  • Development of practical hydrogen storage devices.


A.Walton, J.D.Speight, A.J.Williams, I.R.Harris (2000) ‘A Zinc Coating Method for NdFeB Magnets’. J. Alloys & Compounds, 306, p253-261

A.Walton, J.D.Speight, I.R.Harris (2000) ‘Low Pressure Pack Sublimation: Newly Developed Zinc Coating Process’. J. Surface Eng. Vol.16, No.2, p153, Prize given in the Bodycote paper competition 1999 (invited talk to the Bodycote AGM).

D.B.Willey, D.Pederzolli, A.S.Pratt, J.Swift (Johnson Matthey): A.Walton, I.R.Harris (University ofBirmingham) (2002) ‘Low Temperature Hydrogenation Properties of Platinum Group Metal Treated Nickel Metal Hydride Electrode Alloys’. J.Alloys & Compounds, 330-332, 806-809.

H.W.Langmi, A.Walton, M.M.Almamouri, S.R.Johnson, D.Book, J.D.Speight, P.P.Edwards, I.Gameson, P.A.Anderson, I.R.Harris. (2003) ‘Hydrogen Adsorption in Zeolites A,X,Y and Rho’. J.Alloys & Compounds 356-357, p710-715.

O.Gutfleisch, N.Schlorke-de-Boer, N.Ismail, M.Herrich (IFW Dresden), A.Walton, J.D.Speight, I.R.Harris (University of Birmingham), A.S.Pratt (Johnson Matthey Plc), A.Züttel (University of Fribourg). (2003) ‘Hydrogenation Properties of Nano-Crystalline Mg and Mg2Ni Based Compounds Modified with Platinum Group Metals (PGM’s)’. J.Alloys and Compounds 356-357, p598-602.

Johnson SR, Anderson PA, Edwards PP, Gameson I, Prendergast JW, Almamouri M, Book.D, Harris IR, Speight JD, Walton A (2005) ‘Chemical Activation of MgH2; A New Route to Superior Hydrogen Storage Materials’. Chem.Com, p 2823-2825.

H.W. Langmi, D. Book, A. Walton, S.R. Johnson, M.M. Al-Mamouri, J.D. Speight, P.P. Edwards, I.R. Harris, P.A. Anderson, (2005) ‘Hydrogen Storage in Ion-exchanged Zeolites’. J.Alloys and Compounds, 404: p 637-642.

McKeown NB, Gahnem B, Msayib KJ, Budd PM, Tattershall CE, Mahmood K, Tan S, Book D, Langmi HW, Walton A (2006) ‘Towards Polymer-Based Hydrogen Storage Materials: Engineering Ultramicroporous Cavities within Polymers of Intrinsic Microporosity’. ANGEWANDTE Chemie-International Edition 45 (11) p1804-1807.

Budd PM, Butler A, Selbie J, Mahmood K, McKeown N B, Ghanem B, Msayib K, Book B, Walton A, (2007) ‘The potential of Organic Polymer-Based Hydrogen Storage Materials’. Phys.Chem. 9 (15) p1802-1808.

David WIF, Jones MO, Gregory DH, Jewell CM, Johnson SR, Walton A, Edwards PP (2007) ‘A Mechanism for Non Stoichiometry in the Lithium Amide/Lithium Imide Hydrogen Storage Reaction’. J.American. Chem.Soc, 129 (6) p1594-1601

Ghanem BS, Msayib KJ, McKeown NB, Harris KDM, Pan Z, Budd PM, Butler A, Selbie J, Book D, Walton A, (2007), ‘A Triptycene-based Polymer of Intrinsic Microporosity that Displays Enhanced Surface Area and Hydrogen Adsorption’. Chem.Com (1), p67-69.

Chater P A, Anderson PA, Prendergast, Walton A, Mann VSJ, Book D, William DIF, Johnson SR,Edwards PP, (2007). ‘Synthesis and Characterization of Amide-Borohydrides: New Complex Light Hydrides for Potential Hydrogen Storage’ J.Alloys and Compounds, Vol 446-447, p 350-354

Y.Pivak, R.Gremaud, K.Gross, M. Gonsalez-Silveira, A.Walton, H.Schreuders, B.Dam and R.Griessen. (2009) ‘Effect of the film substrate on the thermodynamic properties of the PdHx studied by hydrogenography’, Scripta Materialis, Vol 60, Issue 5, p348

B. Paik, A. Walton, V. Mann, D. Book, I.P. Jones, I.R. Harris, (2010) Microstructure of ball milled MgH2 powders upon hydrogen cycling: An electron microscopy study; International Journal of Hydrogen Energy, Volume 35, Issue 17, p 9012-9020

B. Paik, I.P. Jones, A. Walton, V. Mann, D. Book, I.R. Harris, (2010). ‘Evolution of microstructure in MgH2 powder particles during high energy ball milling and hydrogen cycling’; Journal of Alloys and Compounds Vol 492, Issue, p515

G.S. Ghanem, M. Hashem, K.D.M. Harris, K.J. Msayib, M.Xu, P.M. Budd, N. Chaukura, D. Book, S. Tedds, A. Walton, N.B. McKeown, (2010). 'Triptycene based polymers of intrinsic microporosity ; organic materials that can be tailored for gas adsorption'; Journal of Macromoelcules 43, 5287-5294.

K. Binnemans, P.T. Jones, B. Blanpain, T.V. Gerven, Y. Yang, A. Walton, M. Buchert, (2013). 'Recycling of rare earths: a critical review'; Journal of Cleaner Production, 51, p1-22

R.S. Sheridan, A.J. Williams, I.R. Harris, A. Walton, (2013). 'Improved HDDR processing route for production of anisotropic poder from sintered NdFeB type magnets'; Journal of Magnetism and Magnetic Materials 350, p114-118.

B. Spreccher, Y. Xiao, A. Walton, J. Speight, R. Harris, R. Kleijn, G. Visser, G.J. Kramer, (2014). 'Life cycle inventory of the production of rare earths and the subsequent production of NdFeB rare earth permanent magnets'; Environmental Science & Technology 48(7), p3951–3958

A. Walton, H. Yi, N.A. Rowson, J.D. Speight, V.S.J. Mann, R.S. Sheridan, A. Bradshaw, I.R. Harris, A.J. Williams, (2015). ‘The use of hydrogen to separate and recycle neodymium-iron-boron-type magnets from electronic waste’; Journal of Cleaner Production, 104, p236-241

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