Summer Research 2010. I did a research on growing proton-conducting polymer nanoporous gold electrodes for fuel cell applications.

1. Growing Proton-Conducting Polymer Within Nanoporous Gold Electrodes
To Build Fuel Cells
Noel Zulkifli, Carlos Escobar, Dr. G. Kane Jennings
What is a Fuel Cell? Method Conclusions
A fuel cell is a device designed to covert hydrogen to Step #1: Preparation of NPGL on Glass
electricity. A fuel cell consists of an anode, cathode and a
1 We are able to grow pNBF6 polymer within NPGL
proton exchange membrane. Hydrogen fuel and oxygen gas
pores at short times in the monomer solution.
are required to produce energy and water as a byproduct:
NPGL
2H2 + O2 2H2O + Energy Scanning Electron 2 SEM proves that growing polymer for over 5min
Glass Microscopy (SEM)
1 2 3 4 5 show signs of overgrowth.
* images from Based Photoelectrochemical Energy Conversion, Peter N. Ciesielski, 2010
Step #2: Growing the Polymer Step #3: Sulfonation 3 Long times in acteyl sulfate shows successful
Proton Exchange Membrane sulfonation while still maintaining some polymer.
Current fabrication methods of proton exchange membrane
(PEM) have poor utilization of platinum catalyst leading to
waste of expensive materials. This research aims to radically
alter PEM fuel cell fabrication and processing by integrating 1 2 3 4 Future Directions
proton conduction and gas diffusion pathways with catalyst
interface into a single network, built within nanoporous gold
1 Test proton conduction and oxygen transfer from
electrodes called the “Electrode Membrane.” Results both sides by using a porous support instead of
glass.
-4-
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Electrochemical Impedance Spectroscopy (EIS)
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Electrode Membrane
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2 Grow polymer from surfaces that contain Pt particles
&1 )&<O! ! P ( ! + ’ , . ," ) : ,< ! ! R ’
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hydrophillic
&, # ( 2! 2 ’ $8 >, #$ ;
and test oxygen reduction at the cathodic interface.
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Duration of Growing the Polymer
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10,000,000
(PEM) NPGL 3 Determine the effect of ionomer composition on
( 8! 0 ’ 1 ’ ! ,!$& . )1
Above 5min show
!" - #+G ( ) , ,!
!$ 0 ’ 1) ! ; ’ $ ! :
)! ’ ++ ! 0# ) 8!A . !#
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Glass signs of overgrowth proton conduction, rate of oxygen reduction
!$ # ’ ( ’ : )1!+ -
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hydrophobic domain reaction, water transport and the performance of
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Impedance (Ω·cm2)
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Electrode Membrane the fuel cell.
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gold leaf 103 10min Pt catalyst
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After Polymer Growth 119° ± 5 67° ± 4
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Acknowledgements
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100nm After Sulfonation 119° ± 4 67° ± 3