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Alkaline Methanol Fuel Cell
Tam DuongDr. Yushan Yan
Fuel CellElectrochemical device
Convert chemical energy into electricity
Having two electrodes: Positive (cathode) and Negative (anode)
Reaction with the presence of electrolyte.
Working depends on the catalyst
System
Cell system with rotating disk, reference electrode, platinum wire, and gas vent.
Why Methanol Fuel Cell? Methanol has high energy density.
Easy to store in liquid state in room temperature.
Fuel cell works as a battery that doesn’t go down or need to be charged.
Highly promising to serve as a power source for cell phones, and laptops.
Reduce the pollution
Methanol Fuel Cell Alkaline Methanol Fuel Cell: Hydroxide flow from cathode to
anode.
Waste Products: Water and Carbon Dioxide Toxic and flammable In 2005, ICAO (International Civil Avitation Organization) DGP
(Dangerous Food Panel) voted to allow passengers to carry and uses micro fuel cell when travelling aboard.
OH
eOHO
6
632
322
OH
eOHCO
OHOHCH
65
6
22
3
Current
Basic Information Nafion membrane (ionomer)
Qualified Power (W): 100 kW to 1MW
Working temperature: 90 – 120 deg C
Electrical efficiency:-Cell : 20-30%-System: 10-20%
Typical fuel cell: 0.6 – 0.7 V
Method of Collecting Data
Coating the glassy carbon electrode with the calculated volume of catalyst
• Sample Volume = (Electrode Area)*(Loading/Area)*(Solution Concentration)
• 10 ul of .05% Nafion
Making 250 mL electrolyte (0.1M KOH) Setting the cell up with Pt wire and the reference
electrode Connecting the gas vent Blowing gas into the cell and record data
Cyclic Voltammetry
One type of potential electrochemical measurement. (Potential scanning)
Forward sweep: reversible oxidation Reversed sweep: Reduction Used to calculate the surface area
mA
V
Oxid
ati
on
R
educt
ion
Basic Shape of a CV curve
Tested Samples
Loadings(µg/cm2)
ORR(without MeOH)
ORR(With
MeOH)
MOR HOR
Ag/C 50 + + - -
Ag/C 100 + + - -
AgNW 50 + + - -
AgNW 100 + + - -
AgNW 600 + + - -
Au 100 + + - -
SeNW 300 + + - -
PdNT 50 + + + +
Pd/Pt 100 + + + +
Pd/Pt 150 + + + +
Ni 320 + + - -
Table of Samples and Results
Calculating the Theoretical Surface Area
drm
A..
3
4 3
Calculating Experimental Surface Area
Area (CV graph) [mA.V] x speed [1/V] x ratio [mC/mA]
Constant [mC/cm2] x loading [µg/cm2] x area (electrode) [cm2] x 0.77
m
A
ETEK with Nafion (ORR)
-10
-5
0
5
10
15
20
25
30
35
-1 -0.5 0 0.5
E/V vs Hg/HgOI/m
Acm
-2
ORR curve without methanolat 5 mV/s scanning speed
ORR curve with methanol at 5 mV/s scanning speed
ETEK with Nafion (HOR and MOR)
HOR curve with 300 rpm at 5 mV/s scanning speed
MOR curve at 50 mV/s scanning speed
SeNW (ORR)
SeNW (HOR and MOR)
HOR curve with 300 rpm at 5 mV/s scanning speed
MOR curve at 50 mV/s scanning speed
Gold NanoTube (ORR)
Gold NanoTube (HOR and MOR)
HOR with 300 rpm at 5 mV/s
MOR at 50 mV/s
Palladium Nanotube
ORR with 1600 rpm at5 mV/s
Chronoamperometryat -0.15 V vs Hg/HgO
Palladium Nanotube (HOR and MOR)
HOR with 300 rpm at 5 mV/s
MOR at 50 mV/s
Silver Nanowire 600 µg (ORR)
Silver Nanowire 600 µg (MOR)
Silver Nanowire (100 µg)
HOR with 300 rpm at 5 mV/s
ORR with 1600 rpm at 5 mV/s
Silver Nanowire 50ug (ORR)
Silver Nanowire 50ug (HOR and MOR)
HOR with 300 rpm at 5 mV/s
MOR at 50 mV/s
Palladium and Platinum
ORR with 1600 rpm at 5 mV/s
Chronoamperometry at -0.15 V vs Hg/HgO
Palladium/Platinum (HOR and MOR)
HOR with 300 rpm at 5 mV/s
MOR at 50 mV/s
Ag/C (ORR)
ORR_Ag/C (50 ug/cm2) ORR_Ag/C (100 ug/cm2)
Conclusion Platinum nanotube, palladium nanotube work for
HOR, MOR, and ORR. Silver on carbon, silver nanowires, gold
nanotube, selenium nanowires work for ORR even with methanol.
Future Work Testing platinum/silver alloy Making silver nanowires