developments in plasma based fuel cell research at the
TRANSCRIPT
ARNAM 2006 Annual Workshop29th June 2006
Developments in Plasma Based Fuel CellResearch at the Australian National University
Devin Ramdutt1, Amael Caillard1,3, Cormac Corr1, Weitang Li1, BradLadewig2, Christine Charles1, Rod Boswell1, Andrew Dicks2 and PascalBrault3.1. Space Plasma, Power and Propulsion (SP3), The Research School of Physical Sciences andEngineering, The Australian National University, Canberra, ACT, Australia, 0200.2. Nanomac, School of Engineering, The University of Queensland, Brisbane, QLD, Australia, 4072.3. GREMI-CNRS Laboratory, University of Orléans, BP 6744, F-45067, Orléans, France
ARNAM 2006 Annual Workshop29th June 2006
Outline
• What is a fuel cell and the different types.• Proton Exchange Membrane Fuel Cells.• Sputter Deposition using plasmas.• Depth profiling and RBS analysis.• Carbon nano-wires• Boron nano-wires• Deposition of proton conducting membranes inpolymerising plasmas.• Effects of plasmas on Nafion
ARNAM 2006 Annual Workshop29th June 2006
Types of Fuel Cells
• An overpriced battery.
• 2H2 + O2 -> 2H2O + energy
ARNAM 2006 Annual Workshop29th June 2006
Proton Exchange Membrane (PEM) Fuel Cells
ARNAM 2006 Annual Workshop29th June 2006
Sputter Deposition in an Argon Plasma
ARNAM 2006 Annual Workshop29th June 2006
Depth Profiling using RBS and PlatinumLoading
Depth profile of Pt on E-Tek GDL
0
5
10
15
20
25
30
0 50 100 150 200 250 300 350 400 450 500
Distance (nm)
Pt
den
sity
(x1
01
5 a
tom
s/cm
2)
ptc11b.rbs Bi-exponential fit
RBS spectra of Pt on GDL deposited in a 1kW Ar plasma for 20 minutes
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
0.15 0.35 0.55 0.75 0.95 1.15 1.35 1.55 1.75 1.95 2.15
Energy (MeV)
Co
un
ts
€
g( t) = Ae−tB +Ce
−tD
Depth profile data can be fit using abi-exponential function that fitsanomalous diffusion.
E-Tek Reference100010001000
Plasma Power(W)
20105
Deposition Time(min)
0.350.0260.0190.008
Pt Loading(mg/cm2)
ARNAM 2006 Annual Workshop29th June 2006
Performance of Plasma Sputtered Electrodes
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 300 600 900 1200 1500 1800Current Density (mA/cm2)
Pot
entia
l (V
)
ARNAM 2006 Annual Workshop29th June 2006
Carbon Nano-fibres and Co-Sputtering ofPlatinum
Rotarypump
Convectrongauge
DC Substrate bias
Pt target bias
Nitarget
Pttarget
Current generator(heater)
Input gas Ar-CH4
ICP antenna powered by a RFgenerator & matching box
Carboncloth
CNF deposition on to carbon paper
Pt nano-particles deposition on CNFs
ARNAM 2006 Annual Workshop29th June 2006
Boron Nano-Wires
ARNAM 2006 Annual Workshop29th June 2006
Proton Conducting Membranes Produced byPlasma Enhanced Chemical Vapour Deposition
(PECVD)
(b)
Plasma membrane isdeposited 6 µm into the
GDL
ARNAM 2006 Annual Workshop29th June 2006
Understanding Effects of Low Power Plasmason Nafion Membranes
€
Eion (J.cm−2) = teµion (Vp −Vf )
= tenion2e(Vp −Vf )
M(Vp −Vf )
≈ tenion2eVp
MVp
Energy dose calculation to Nafionsurface from argon ions in plasma.
Plasma ParametersVp = 32 VVf = 1 - 2 Vnion = 109 - 1011 ions.cm-3
Exposure time = 2 - 120 seconds
ARNAM 2006 Annual Workshop29th June 2006
Understanding Effects of Plasmas on NafionMembranes
Water contact angle
ARNAM 2006 Annual Workshop29th June 2006
Understanding Effects of Plasmas on NafionMembranes
Proton conductivity
ARNAM 2006 Annual Workshop29th June 2006
Understanding Effects of Plasmas on NafionMembranes
Surface morphology
0.476 nm60 secondexposure
0.579 nm10 secondexposure
0.651 nmReferenceRMS RoughnessSample
ARNAM 2006 Annual Workshop29th June 2006
Conclusions
• Our goal for a plasma base fuel cell is well under way.• We are using plasmas to deposits the catalyst layers on ourcarbon GDL.• We are engineering our surfaces in the form of nano -tubes -wires -fibers -belts to increase the available surface for thecatalyst to deposit on.• We are looking at depositing proton conducting polymers usingPECVD.• It is my goal to have a plasma processing production linepumping out model T fuel cell very shortly.