Processing of RNickel Catalysts for Alkaline Fuel Cell Applications

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Processing of R-Nickel Catalysts for Alkaline
Fuel Cell Applications Helsinki University of
Technology Laboratory of Industrial Chemistry Dr.
Juha Linnekoski
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Industrial Chemistry
Process Research
- Particularly Catalytic Processes

• RESEARCH RELATED TO FUEL CELLS
• Production of Hydrogen
• Fuel Cell catalysts
• Catalyst preparation with ALD

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Fuel cells and related activities at VTT

• Low-temperature fuel cells
• Construction of stacks
• Catalysts for PEM, AFC and
• hydrogen generator
• Bipolar plate development
• Balance of plant
• High-temperature fuel cells
• SOFC research reviewed in other presentations
• Supercapacitors
• Activated carbon and polymer electrodes
• Liquid and solid electrolytes
• Applications of supercapacitors

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Aim of the studies

• Replace Pt in Hydrogen oxidation reaction (HOR)
  by Raney Nickel (R-Ni)
• Non-support R-Ni suffer from insufficient
  conductivity
• Enhanced by using Copper, which not stable but
  dissolves
• Shim et al. (J. Power Sources, 74(1)) added
  carbon by wet method
• In this work, to enhance conductivity Raney
  nickel catalysts were alloyed with carbon

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Mechanical alloying

• Raney nickel with Black Pearls 2000
• In a planetary-type ball mill Fritsch
  Pulverisette 5
• Argon atmosphere with
• Nickel to carbon ratio 101
• Milling time 30 minutes

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SEM pictures of R-Ni powder
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Activation of Raney Ni

• The specific surface area 1.54 m2/g

M. Shulze et al. Applied Surface Science 179
(2001).
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X-ray diffraction curves
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Addition of Pt on R-Ni

• Platinum addition after milling
• Platinum prepared by reduction of PtCl2
• Hydrotriorganoborates to form nano-sized powders.
  
• The amount of platinum was varied from 0.5 to 10
  wt. of the amount of nickel.

Bönnemann et. al. J. Mol. Catal., 86(1-3)
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TEM picture of Pt on C
Bönnemann et. al. J. Mol. Catal., 86(1-3)
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Electrochemical activity

• Hydrogen oxidation reaction
• Flat electrodes of 10 cm2 of active area for half
  cell configuration.
• The gas diffusion layer consisted of PTFE in
  acetylene black and nickel mesh as current
  collector
• Active layer same diffusion material with 73
  mg/cm2 of prepared nickel powder.
• Polarization measured at 333 K in 100 hydrogen
  flow
• As a comparision a commercial Pt catalyst was used

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Polarisation of ball milled
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Addition of Pt on R-Ni
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Acknowledgement

• The National Technology Development Agency
• (TEKES)
• Hydrocell

Oy Hydrocell Ltd Minkkikatu 1-3 04430
Järvenpää FINLAND
www.hydrocell.fi info_at_hydrocell.fi