Presentation of Interfacultary Project

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Presentation of Interfacultary Project
The versatility of nickel oxide from batteries to
smart windows
July 14, 2004
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Group members
Marko Nieuwenhuizen ( Project leader) ST Xin Wang
ST Brian Pauw ST Jaap Bastiaansen TN Kare
n Scholz Tutor
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Overview

• Introduction
• Current applications
• Computational modelling
• Discussion and conclusions
• Questions

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Introduction
Goals

• Explore current applications
• Investigate modifications
• Investigate applied models
• Discuss future applications

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Current applications

• Batteries (NiCd, NiMH)
• Electrochromic devices
• Catalyst material
• Electrode in fuel cells
• Thermoelectric applications

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Batteries
Panasonic, Nickel Metal Hydride batteries
Handbook, 2003
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Half cell reactions
Positive Electrode Ni(OH)2 OH- NiOOH
H2O e- Negative electrode M H2O e-
MHab OH- Overall reaction Ni(OH)2
M NiOOH MHab
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Problems occurring in batteries
Phase transitions
Oxygen evolution reaction
4 OH- O2 2H2O 4e-
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Electrochromic devices
Information display
Diffuse scattering
Absorption
Redraw from Cranqvist C.G. Handbook of inorganic
electrochromic materials
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Electrochromic applications
Information display
Variable reflectance mirror
Specular reflection
Diffuse scattering
Absorption
Absorption
Redraw from Cranqvist C.G. Handbook of inorganic
electrochromic materials
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Smart window
Transmission
Absorption
Redraw from Cranqvist C.G. Handbook of inorganic
electrochromic materials
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Smart window
Variable emittance surface
Transmission
Emitting
Infrared absorbing
Absorption
Non-emitting
Infrared reflecting
Redraw from Cranqvist C.G. Handbook of inorganic
electrochromic materials
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Catalyst material

• O2 evolution desired reaction in
  electrocatalysis
• Electro-oxidation of alcohols

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Fuel cells

• Alkaline Fuel Cell (AFC)
• Molten Carbonate Fuel Cell (MCFC)
• Phosphoric Acid Fuel Cell (PAFC)
• Proton Exchange Membrane Fuel Cell (PEMFC)
• Solid Oxide Fuel Cell (SOFC)
• Direct Methanol Fuel Cell (DMFC)

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Molten Carbonate Fuel Cell (MCFC)
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Some problems

• NiO dissolves into the electrolyte
• Decrease of surface area
• Short-circuiting

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Several solutions

• Modifications in the composition of gas mixtures
• Varying partial pressure of CO2,total pressure
• LiFeO2, Li2CoO2, Li2MnO3 and La1-xSrxCoO3 as
  replacement materials for the NiO cathodes
• ZnO impregnated NiO cathodes
• NiO cores covered with an outer layer of Li (Co)
  oxide

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Current applications

• Batteries (NiCd, NiMH)
• Electrochromic devices
• Catalyst material
• Electrode in fuel cells
• Thermoelectric applications

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Thermoelectric effect
Temperature gradient ? Potential difference
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Gas sensors

• Hydrogen detector by coating with pt
• CO detector by coating with au
• Hydrogen detector by coating with pt
• Doping Li and Na to improve thermoelectric
  properties

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Source W.Shin, www.aist.go.jp
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Computational modelling

• Molecular modelling
• - Using statistical mechanics and Newtons
  second law
• - Calculating atomic details

Limitations - Purely classical motions -
Electron motions are not considered

• Electronic structure modeling
• - Using quantum mechanics

Limitations - Larger systems means larger
approximations - Less practical use for systems
gt50 atoms
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Modelling applied to NiO

• Crystal structure after doping
• Difussion models
• Band-gap calculations

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Discussion and conclusions

• Many similarities between electrochromism and
  energy storage
• Possible applications, using electrochromism
• Thermoelectric energy sources ?
• Stabilising nickel oxide in MCFC

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Acknowledgements
Prof. dr. P. Notten Dr. M. Wehrens-Dijksma Ir. K.
Scholz Dr. Ir. J. Reijenga
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Questions?
For more information visit our website on
Students.chem.tue.nl/ifp10