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1
Advanced Cathode Catalysts and Supports for
PEM Fuel CellsMark K. Debe3M CompanyMay 20, 2009
Project ID: FC_17_DebeThis presentation does not contain any proprietary, confidential, or otherwise restricted information
2009 DOE Hydrogen Program Review
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18-22
OverviewTimeline
Project start : April 1, 2007Project end : March 30, 201150% Complete (3/30/09)
BarriersA. Electrode and MEA DurabilityB. Stack Material & Mfg CostC. Electrode and MEA Performance
DOE Technical TargetsBudgetTotal Project funding $10.43MM
$8.34 MM DOE and FFRDC$2.09 MM 3M share
Received in FY08: $1.621 MMEst. Funding for FY09: $1.962MM
Dalhousie University (J. Dahn, D. Stevens)JPL (S. R. Narayanan, C. Hays)ANL (N. Markovic, V. Stamenkovic)Project Management – 3M
Partners
Electrocatalyst/ MEA 2010 2015
Lifetime Hrs, > 80oC 2000 5000
Mass Activity(A/mg) 0.44 0.44PGM, (g/KW rated) 0.3 0.2
Performance @ Rated (W/cm2 ) @ 0.8V
10.25
10.25
Additional InteractionsGM Fuel Cell Activities - Honeoye FallsLANL(NIST), ORNL(TEM), ANL (modeling) Proton Energy Sys.; Giner EC Sys. LLCVarious Vendors: for GDM components
3
Define and implement multiple strategies for increasing NSTF support surface area, catalyst activity and durability, with total loadings of < 0.25 mg-Pt/cm2 /MEAWork closely with subcontractors to fabricate and screen new electrocatalysts using high throughput characterization methods, for activity and durability gainsConduct fundamental studies of the NSTF catalyst activities for ORRApply more severe accelerated tests to benchmark the NSTF/MEA durabilityDefine and implement multiple strategies to optimize the MEA water managementAdvance the high volume roll-good NSTF catalyst / membrane integrationWork closely with system integrator to validate NSTF functional properties/issues
Development of a durable, low cost, high performance cathode electrode (catalyst and support), that is fully integrated into a fuel cell membrane electrode assembly with gas diffusion media, fabricated by high volume capable processes, and is able to meet or exceed the 2015 DOE targets.
Overall Project Objectives
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 -22
Objectives for Past Year
4
4/1/09
Project Timeline and MilestonesBudget Period 1 Budget Period 2
4/1/07 01/01/10
Q1 Q12 Q16Q11
= Go-No Go for Extension of Task
= Go-No Go for Stack Testing = Go-No Go for Large Area, Single Cell Durability Tests
Task 1.3 – Activity Optimization
Task 1.1 – ECSA OptimizationTask 1.2 – Cat. Fundamentals
Task 2 – Cat. Durability Gains
Task 5.1 PEM Integration, Task 5.2 GDL Integration
Task 3
Task 4 – Support durabilityTask 5.3
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Q2 Q3 Q4 Q5
5/20/093/31/11
Q6 Q7 Q8 Q9 Q10
Task 6 – Start-up, conditioning
5
Technical Progress: Task 1 - NSTF catalyst and support fundamentals
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
NSTF fundamentals – A key focus ~ 500 MEA’s in past 9 months
Increased understanding of fundamentals of whisker geometry:• determining process conditions to generate desired whisker
geometric characteristics (on roll-good production equipment)• two of three designed experiments completed for whisker growth: SEM characterization, fuel cell testing for 14 metrics• relating whisker characteristics to ultimate catalyst ECSA,
particle size, shape, and how those relate to activity• developed model for calculating catalyst ECSA as a
function of whisker geometric factors: N(µm-1),L(µm), ρalloy, Pt loading, roughness factors, backplane deposition
Increase knowledge of how to control the critical factors determining ORR for a given catalyst type and loading: • catalyst composition (> 30 Pt alloys in hundreds of MEAs)• grain size, optimum crystal facets, lattice parameters • surface structure or composition modulation.
0.00 0.03 0.06 0.09 0.12 0.15 0.18 0.210.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
NucleationRegion
Metal islands at preferred sites Square-truncated pyramid crystallites
Elongated whiskerett (along the pillar) Whiskerett: a pyramid top on a tilted pillar
6-7 nm
Whisker side plane
Metal deposition
Short Whisker, L = 0.52μm
Aspect ratio ~ 2 in [111] direction.
Whiskerette growing
Nearly Spherical
Shape
Very low extension in [200] direction
Same extension in[111] and [220]
directions
Longest in [311] direction
WAO 2800-4, N = 73/μm2, L = 0.52μm
Ratio for Spherical Grain
Activity vs Grain Size - graph 9
Rat
ios
of (1
11)/(
hkl)
Gra
in S
izes
Pt Loading (mg/cm2)
111/200 111/220 111/311
Pt fcc grain size ratios vs loading
45 50 55 60 65 70 75 80 852
4
6
8
10
12
14
16
18Std. Pt68.7Co28.5Mn2.7 on WAO-1 Whisker Series
Activity vs Grain Size - graph 30
EC
SA
(cm
2 Pt /c
m2 pl
anar )
Pt(111) Grain Size (Angstroms)
WAO-1 ECSA, ML-2 and P4 Coated - 0.05 mg/cm2 WAO-1 ECSA, All P4 Coated - 0.2mg/cm2 WAO-1 ECSA, ML-2 and P4 Coated - 0.15 mg/cm2 WAO-1 ECSA, ML-2 and P4 Coated - 0.1 mg/cm2
ECSA vs fcc grain size & loading
6
Baseline Best-of-Class MEA - Oct., 2007A/C = 0.1/0.15 mgPt/cm2 PtCoMn35 micron 3M PEMNon-standard 3M GDL
Baseline Best-of-Class MEA - Jan., 2009A/C = 0.05/0.10 mgPt/cm2 PtCoMn20 micron 3M PEMImproved 3M GDL
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.00.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
FC12969-937R, V FC12969-937R, HFR FC14654-757, V FC14654-757, HFR FC014693-572, V FC014693-596, HFR
Best of Class 1/22/09FC14654, FC14693
Previous Best : A/C = NSTF PtCoMn 0.1/0.15 mgPt/cm2 PEM: 3M 850 EW, 35 micron; GDL: 3M 2975
New Best of Class: A/C = NSTF PtCoMn 0.05/0.10 mgPt/cm2 PEM: 3M 850 EW, 20 micron; GDL: 3M New
Specifc Power Density Projections- graph 6
Galvanodynamic ScansTcell/DP's = 80/68/68 °C H2/air stoich = 2.0/2.5H2/air Inlet pressure = 150 kPaGDS(0.02, 2, 10 step/dec, 180s/pt) 50 cm2 Quad serpentine cell
HFR
Cel
l Vol
tage
(V) a
nd H
FR (o
hm-c
m2 )
J (A/cm2)
MEA Modifications40% reduction in total Pt loading40% reduction in PEM thicknessImproved GDL
Technical Accomplishments: Higher power density, reduced Pt loading
150 kPa H2/Air, 80oC, 67%RH34% reduction in HF impedance40% reduction in mass transport loss85 mV gain at 2 A/cm2
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.00.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
Galvanodynamic ScansTcell = 80°C H2/air stoich = 2.0/2.5H2/air Inlet pressure = 150 kPaRelative Humidity = 67% GDS(0.02, 2, 10 step/dec, 180s/pt)Both MEA electrodes conditioned50 cm2 Quad serpentine cell
New Best of Class: A/C = NSTF PtCoMn 0.05/0.10 mgPt/cm2 PEM: 3M 850 EW, 20 micron; GDL: 3M New
FC14693-572, Voltage (V), 150kPa FC14693-572, Power (W/cm2), 150kPa FC14654-757, Power (W/cm2), 150kPa FC14654-757, Voltage (V), 150kPa
Specifc Power Density Projections- graph 10
Cel
l Vol
tage
(V) a
nd P
ower
(W/c
m2 )
J (A/cm2)
7
48% reduction in gPt / kW at peak power over 2007 - 2008 baseline40% reduction in mass transport over-potential at 2 A/cm2 at 150kPa
0.1 10.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
MTO = 43 mV @ 2A/cm2
E(V
), H
FR (o
hm-c
m2 ) a
nd E
IR-F
ree(V
)
70 mV/decTafel Slope
43 mV
FC14654-757, V FC14654-757, IR-free FC14654-757
HFR
Galvanodynamic ScansTcell/DP's = 80/68/68oCH2/air stoich = 2.0/2.5H2/air Inlet pressure = 150 kPaGDS(0.02, 2, 10 step/dec, 180s/pt)50 cm2 Quad serpentine cell
Specifc Power Density Projections- graph 2J (A/cm2)
New Best of Class MEA Tafel Plot150 kPa Inlet Pressure
Inverse Specific Power Density150 kPa Inlet Pressure
New Baseline MEA exceeds DOE 2015 targets for Inverse Specific Power Density at 150kPa ( < 0.18 gPt total / kW )and total Pt loading: 0.15 mgPt/cm2 of MEA
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Technical Accomplishments: Higher power density, reduced Pt loading
0.55 0.60 0.65 0.70 0.75 0.800.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
DOE 2015 Target
Galvanodynamic ScansTcell/DP's = 80/68/68 °C H2/air stoich = 2.0/2.5H2/air Inlet pressure = 150 kPaGDS(0.02, 2, 10 step/dec, 180s/pt)Both MEA electrodes conditioned50 cm2 Quad serpentine cell
New Best of Class: A/C = NSTF PtCoMn 0.05/0.10 mgPt/cm2 PEM: 3M 850 EW, 20 micron; GDL: 3M New
FC14654-757FC14693-572
01/22/09
Previous Best of ClassFC12969 - 937R
10/05/07
Cell Voltage (V)
(Spe
cific
Pow
er D
ensi
ty)-1
(gPt
tota
l / k
W)
Specifc Power Density Projections- graph 9
Previous Best : A/C = NSTF PtCoMn 0.1/0.15 mgPt/cm2 PEM: 3M 850 EW, 35 micron; GDL: 3M 2975
80 200 400 600 800 1000 12000.0
0.5
1.0
1.5
2.0
2.5
F- Release Rate FC14109 F- Release Rate FC14098
OCV Hold Conditions:90oC, 50 cm2
H2/Air RH = 30%/30%H2/Air P = 250/200 kPaH2/Air FR= 696/1657 sccm
EXP 021_OCV hold under air - graph 2, data 1
F- Rel
ease
Rat
e (μ
g/cm
2 /day
)
Time (hours)
F - ion release rate vs timeOCV vs time
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Technical Accomplishments: Accelerated Durability Test: OCV Hold
Open Circuit Voltage Hold TestConditions: 90oC, 30% RH, 250 kPa/200 kPa
H2 Air, CF = 696/1657 sccmTargets: 200 hours, H2 crossover < 20 mA/cm2,
F – ion release monitored onlyPEM: 3M 20 µm, with stabilizing additiveCatalyst: NSTF 0.1/0.15 PtCoMn,Results:• > 900 hours with F – rate < 0.5 µg/cm2/day• H2 X-over < 20mA/cm2 for 0 < t < 800 hrs.
H2 Crossover vs time
0 200 400 600 800 1000 1200 14000
10
20
30
40
50
60
70
80
90
100
H2 Crossover FC14109 H2 Crossover FC14098
OCV Hold Conditions:90oC, 50 cm2
H2/Air RH = 30%/30%H2/Air P = 250/200 kPaH2/Air FR= 696/1657 sccm
EXP 021_OCV hold under air - graph 3, data 1
H2 C
ross
over
(mA
/cm
2 )
Time (hours)
0 200 400 600 800 1000 1200 14000.0
0.2
0.4
0.6
0.8
1.0
Catalyst: NSTF PtCoMn (0.10 / 0.15 mgPt/cm2)PEM: 3M, 20 μm , commercialized stabilizing additive
OCV Hold Conditions:90oC, 50 cm2
H2/Air RH = 30%/30%H2/Air P = 250/200 kPaH2/Air FR= 696/1657 sccm
Periodic Short and Crossover Tests Under H2/N2
EXP 021_OCV hold under air - graph 1, data 1
FC14109(1300 hours)
FC14098(900 hours)
OC
V (V
olts
)
Time (hours)
9
Load Cycling DurabilityTest protocol in 2008 Review, FC1 MEA: 0.2 mg/cm2 NSTF PtCoMn, 3M ionomer without stabilizing additives, with mechanical stabilization (W. L. Gore).1st MEA > 7300 hrs reported in 20082nd MEA now completed over 7000 hrsExceeds DOE-2015 5000 hour target
0 1000 2000 3000 4000 5000 6000 70000.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
7 Dispersed MEA'sA/C Catalyst:
Pt/Carbon: 0.4 mg-Pt/cm2 PEM: 3M, no chemical or mechanical stabilization
All 7 failed in 200 - 600 hrs.
Shiva all NSTF Data 021808 - graph 3
2- NSTF MEA's A/C Catalyst:
0.2 mg-Pt/cm2 PtCoMnPEM: 3M ionomer in mechanicalstabilized support, no chemical
stabilization,Both exceeded 7000 hrs.
4 - NSTF MEA's A/C Catalyst:
0.2 mg-Pt/cm2 PtCoMnPEM: 3M, no chemical or mechanical stabilizationAv. Lifetime ~ 3500 hrs
Cel
l Vol
tage
at O
CV
Time (hrs)
Technical Accomplishments: Accelerated High Voltage and Load Cycling
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Hi Voltage CV Cycling0.6 – 1.2 V, 20 mV/sec, 200kPa H2/N2 at 95/95/95 oC cell/dew points .4000 cycles with periodic metrics. (~ stable between 4000 and 12000 cycles.) Results shown for 2 new best of class CCMs: 0.05/0.10 PtCoMn, 20 µm PEM: 2 MEA’s
1) -0.6% loss and +5% gain in Spec. Act.2) -20% and -30 % loss of ECSA (cm2
Pt /cm2geo)
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.60.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
BoC CV 95 - graph 1
Station 11
After Cycling
Initial
80/68/68oC cell, 150/150 KPa inlet, H2/air, CS(2/2.5) GDS(0.02 ->2.0 ->0.02, 10 steps/decade, 120s/pt)
Cel
l Vol
tage
(V)
J (A/cm2)
FC15018 353.DAT FC15018 559.DAT FC15030 319.DAT FC15030 549.DAT
10
New NSTF alloy compositions•All 50 cm2 cell tests at 3M• many tens of new compositions made and tested
DOE/GM metric for ORR activity:•150kPa H2/O2, 100%RH, 0.9V(15-20 min)•Activity targets:0.044 mA/cm2
geo , 0.44 A/mgPt
•Correlation to real H2/air performance?•Different Pt oxidation rates for different alloys?
• Results since Dec. ’08: 100% increase in activity•(33)PtCoMn: 0.164 + 0.024 A/mgPt at 0.1 mgPt/cm2
•(3)PtxMy : 0.33 + 0.01 A/mgPt, at 0.1 mgPt/cm2
0.000 0.005 0.010 0.015 0.020 0.025 0.030 0.035 0.0400.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.10
OR
R(9
00m
V) a
t 5 s
econ
ds (A
/cm
2 plan
ar )
0.15 mgPt/cm2
03/21/09
ORR(900 mV) Absolute Activity at 5 seconds vs 1050 seconds.
PtCo PtNiFe PtCoMn PtM PtCoNi PtCoHf PtCoZr PtCoMn Single Target Dep.
Cathode Pt Loading = 0.1 mg/cm2 or as notedAll compositions and test stations, 50 cm2
ORR Files/ORR's at 5 sec - graph 3, data 3
ORR at t = 1050 seconds (A/cm2Planar )
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Technical Accomplishments: Higher activity alloy catalysts for ORR
0 200 400 600 800 1000 12000.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.15 mgPt/cm2
0.1 mgPt/cm2
T = 1050 secORR Values Taken
T = 5 sec
Standard Pt69Co28Mn3
PtxMy
ORR's at 5 secs - graph 18, data 7
Cur
rent
Den
sity
at 9
00 m
V (m
A/c
m2 pl
anar)
Time (seconds)
0.00 0.08 0.16 0.24 0.32 0.40 0.480
8
16
24
32
40
48
ORR's at 5 secs - graph 6, data 4
DOETargets
0.05 mg/cm2
0.10 mg/cm2
0.15 mg/cm2
0.2 mg/cm2
Abs
olut
e A
ctiv
ity a
t 900
mV
(mA
/cm
2 plan
ar )
Cathode Mass Activity at 900 mV (A/mgPt)
WAO-1, 0.2 mg/cm2 WAO-1, 0.15 mg/cm2 WAO-1, 0.1mg/cm2 WAO-1, 0.05 mg/cm2 New Alloys and controls
11
Technical Accomplishments – NSTF ORR Activity and E1/2from RDEV. Stamenkovic, D. van der Vliet, N. Markovic
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Fundamental Studies of NSTF CatalystsRDE characterization of 3M fabricated NSTF alloy catalysts
30-80 mg sample lots of NSTF catalyst coated whiskers14 alloy sample lots evaluated since December 2008Loading studies determined best loading of 65 µg/cm2
disk3 to 8 repeat measurements for each catalyst typeActivity values obtained at 20oC and 60oCCatalysts are intrinsically “acid washed” in RDE measurement, but not for fuel cell tests.
Post-fabrication processingApplied to as-received NSTF catalystsScreening of process conditions for best activityHigh Resolution SEM characterization
Measure highest kinetic and mass activity of any catalyst reported.Highest E1/2 values reported => strong case for setting new standard of measurement at 950 mVIdentified optimum post-fabrication parameters for increased activity
Results
NSTF RDE Polarization Curves(up-voltage sweep shown)
0.6 0.7 0.8 0.9 1.0 1.1-2.0
-1.6
-1.2
-0.8
-0.4
0.0
E1/2 = 0.951
RDE Activity Plots - graph 14, data 4
60oC20 mV/secUpscan65 μgPt/cm2
disk1600 rpm, 20 mV/sec0.1M HClO4NSTF as received
PtM
PtNiFePtCoMn
Pt
I (m
A)
E (V vs RHE)
DiffusionEffects at 0.9
12
Technical Accomplishments – NSTF ORR Activity and E1/2 from RDEV. Stamenkovic, D. van der Vliet, N. Markovic
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Results (continued)
TKK 5nm Pt/C *
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0
1
2
3
4
5
6
7
8
9
10
All 65 μgPt/cm2disk
1600 rpm, 20 mV/sec0.1M HClO4
DOE Target = 0.72
RDE Activity Plots - graph 6
Spe
cific
Act
ivity
at 9
00 m
V (m
A/c
m2 P
t)
60oC
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.80.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
As-Received Alloy Values
PtPtCoPtNiFePtCoMnPtMPtCoNiPtCoZr
Unit slope line
RDE Activity Plots - graph 5, data 3
Fuel
cel
l Mas
s A
ctiv
ity 9
00 m
V a
nd 8
0o C (A
/mg Pt
)
RDE NSTF Alloy Mass Activities at 900 mV and 60oC (A/mgPt )
50 cm2 80oC Mass Activities, 1050 sec 50 cm2 80oC Mass Activities, 5 sec
Mass and specific activities of new NSTF alloy candidates can exceed DOE 2015 targetsANL RDE and 3M 50cm2 fuel cell mass activities at 900 mV quantitatively close: FC 5 sec ORR activity values closer to RDE values.Post fabrication treatment can further increase activities of several alloys tested.Several exceed the DOE 2015 mass activity target
TKK 5nm Pt/C *
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
DOE 2015 Target = 0.44 A/mg
RDE Activity Plots - graph 7, data 3
Mas
s A
ctiv
ity a
t 900
mV
(A/m
g Pt)
60oC
13
Technical Accomplishments: New NSTF catalystsProf. Jeff Dahn, David Stevens, Arnd Garsuch, and students
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Advanced catalysts by compositional spread screening at Dalhousie University
Example of composition control with
PtCoMn
64-electrode arrays of thin film catalysts deposited onto NSTF whiskers, made into MEAs at 3M, tested at Dal. U.129 libraries fabricated and tested through 3/20/09 (vs. 60 last yr.)
• 3 basic configurations (over, under, intermixed w/Pt)• 16 Pt binary, 10 Pt ternary, 10 Pt compound systems
investigated in the intermixed configuration) (vs. 25 last yr.)Compositional, structural and functional performance mapping by: electron microprobe, XPS, XRD, ECSA, ORR, high V cycling durability, acid soak resistance.Extensive proprietary results limit what can be shown
14
Technical Accomplishments: Example: Pt1-xCxProf. Jeff Dahn, David Stevens, Arnd Garsuch, and students
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
0 250 500-0.8
0
0.8
0 250 500 0 250 500 0 250 500Cell Potential (mV)
0 250 500 0 250 500 0 250 500 0 250 500
-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8
Cur
rent
Den
sity
(mA
/cm
2 )
-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8Pt1-xCx – CV’s Measured in Fuel Cell
0 250 500-0.8
0
0.8
0 250 500 0 250 500 0 250 500Cell Potential (mV)
0 250 500 0 250 500 0 250 500 0 250 500
-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8
Cur
rent
Den
sity
(mA
/cm
2 )
-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8C
As assembled After break-inPt Reference
Pt
Pt
0 250 500-0.8
0
0.8
0 250 500 0 250 500 0 250 500Cell Potential (mV)
0 250 500 0 250 500 0 250 500 0 250 500
-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8
Cur
rent
Den
sity
(mA
/cm
2 )
-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8Pt1-xCx – CV’s Measured in Fuel Cell
0 250 500-0.8
0
0.8
0 250 500 0 250 500 0 250 500Cell Potential (mV)
0 250 500 0 250 500 0 250 500 0 250 500
-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8
Cur
rent
Den
sity
(mA
/cm
2 )
-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8-0.8
0
0.8C
As assembled After break-inPt Reference
Pt
Pt
0 0.2 0.4 0.6
x in Pt1-xCx
3.91
3.92
3.93
3.94
Latt
ice
const
ant
0
2
4
6
8
10
Gra
in s
ize
(nm
)
Pt1-xCx – XRD
0 0.2 0.4 0.6
x in Pt1-xCx
3.91
3.92
3.93
3.94
Latt
ice
const
ant
0
2
4
6
8
10
Gra
in s
ize
(nm
)
Pt1-xCx – XRD
30 40 50Scattering angle (deg.)
Inte
nsi
ty (
counts
) (a
rb.
scal
e)
XRDPt1-xCx
C 30 40 50Scattering angle (deg.)
Inte
nsi
ty (
counts
) (a
rb.
scal
e)
XRDPt1-xCx
C
100 120 140 160 180Radial distance (mm)
0
3
6
9
12
15
SEF
(cm
2E
C/c
m2G
EO)
As assembledAfter thermal cycling
Pt1-xCx – ECSA
Increasing C content
As AssembledAfter Break-in conditioning
100 120 140 160 180Radial distance (mm)
0
3
6
9
12
15
SEF
(cm
2E
C/c
m2G
EO)
As assembledAfter thermal cycling
Pt1-xCx – ECSA
Increasing C content
As AssembledAfter Break-in conditioning
• fcc(hkl) grain sizes• Pt fcc lattice parameter• Cyclic voltammograms• ECSA before and after break-
in or high voltage cycling• ORR before and after high
voltage cycling.• After acid corrosion • HOR
Examples of 64 Array Mappings vs Compositions:
100 120 140 160 180Radial distance (mm)
0
3
6
9
12
15
SEF
(cm
2EC/c
m2G
EO)
Before CV cyclingAfter CV cycling
Pt1-xCx – ECSA’s – 0.6 – 1.2 V cycling
Increasing C content
100 120 140 160 180Radial distance (mm)
0
3
6
9
12
15
SEF
(cm
2EC/c
m2G
EO)
Before CV cyclingAfter CV cycling
Pt1-xCx – ECSA’s – 0.6 – 1.2 V cycling
Increasing C content
15
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Technical Accomplishments and Progress: GDL Optimization for NSTF CCM
Electrode backing (EB) carbon paper : Designed Experiment7 commercial roll-good papers
Variables: wet proofing and MPL coating area weight (necessary due to variable EB)3 commercial fully coated GDLs also evaluated
Results: Fuel cell results for all were significantly poorer than 3M baseline GDL
Baseline carbon paper improvement : Designed ExperimentVariables : wet proofing and MPL area weightsSeven fuel cell performance metrics
Results:No single set of GDL parameters were optimum for all seven fuel cell metrics.For steady state cool performance, optimal GDL parameters were different for dry conditions (0 % RH) and wet conditions (100 % RH).Good second order linear regression fits were obtained for three responses (PDS, cathode stoich. sensitivity, and % RH sensitivity at 90/60/60 oC).
Asymmetric anode/cathode GDLs with baseline EB paper : Designed Experiment24-1 factorial with center point replication Variables : wet proofing and MPL coating area weight Still in progress - Largest improvement so far was for extreme difference for anode and cathode GDLs: high wet proofing and MPL weight for anode and low wet proofing and MPL weight for anode.
16
Best GDL Approaches Identified to Date
Technical Accomplishments and Progress: GDL Optimization for NSTF CCM
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Greatest higher temperature improvements were for GDL Type B (15 mV for PDS and 30 to 50 mV for GDS).Generally poorer steady state cool performance results than for baseline GDL. Overall best results with minimal impact on steady state cool performance was for GDL D.
PDS, 70 C
GDS, 7.35 psig, 80 C
GDS, 14 psig, 85
C
Cathode Stoich
Sensitivity
% RH Sens.,
V at J = 1.2
V at J = 1.5
V at J = 1.5
V at 1.4 CS, 80 C
Volts at 90/50/50
C/%RH/%RH
30 C, 0/0
30 C, 100/100
40 C, 0/0
40 C, 100/100
Baseline GDL 0.607 0.540 0.600 0.522 0.588 0.342 0.209 0.540 0.250
GDL A 0.603 0.584 0.625 0.521 0.612 0.305 0.172 0.490 0.203
GDL B 0.623 0.591 0.628 0.531 0.536 0.295 0.120 0.514 0.169
GDL C 0.602 0.578 0.629 0.498 0.596 0.277 0.130 0.467 0.154
GDL D 0.595 0.567 0.614 0.510 0.612 0.334 0.200 0.549 0.235
GDL Steady State Cool Start amps/cm2 at 0.6 V
17
CollaborationsSubcontractors
Dalhousie University : Subcontractor, extensive collaborationANL (Markovic group): Subcontractor, extensive collaborationNASA-JPL: Subcontractor, extensive collaboration
System Integrators and stack manufacturers (partial list)GM Fuel Cell Activities -Honeoye Falls: Extensive collaboration outside of DOE H2program with materials generated at 3M under this contract. Multi-year single cell performance and activity validations, stack testing, cold/freeze start and water management evaluations, PEM and GDL integration, durability testing, fundamental modeling studies.Proton Energy Systems – Performance testing of NSTF MEAs in electrolyzers. Moderate interaction, started in past year and ongoing.Giner EC Systems, LLC – Performance testing of NSTF MEAs in electrolyzers. Moderate interaction, started in past year and ongoing.
National LaboratoriesLANL (Borup group) – Neutron imaging of NSTF MEA’s at NIST. Occasional.ORNL (K. More) - TEM imaging of NSTF catalysts. Occasional.ANL (Ahluwalia group) - Systems modeling with 3M supplied NSTF MEA property and functional performance data as requested. Ongoing for several years.
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18-22
18
Future Work
Cathode Catalyst Mass Activity GainContinue to fabricate and test new catalyst compositions and structures to exceed target mass activity of 0.44 A/mgPt and which meet all other performance requirements.Achieve 50% gain in surface area of NSTF supports over current NSTF baseline without loss of specific activity or durability under most severe accelerated test.
Water Management ImprovementOptimize the GDL materials and physical construction for more effective liquid water transport at low temperatures without compromising high temperature performance under dry conditions. Tailor the GDL for both anode and cathode independently to optimize performance over a wider range of operating conditions.
Start-up conditioning (New Task 6)Continue to explore break-in conditioning protocols and catalyst/membrane components to reduce MEA break-in conditioning time to < 3 hours.
Durability ImprovementReduce by 50% any losses in surface area, activity or mass transport over-potential under the more severe fast high voltage cycling protocol (4000 cycles, 0.6 – 1.2 V under H2/N2 at 20mV/sec at 95/95/95 oC).
Stack testingInitiate Task 3, to begin MEA component down-selection for large area, single cell
performance and durability testing.
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
19
Characteristic Units Targets2010 / 2015
3M Status – 3/09(mfg’d roll-good )
PGM Total Content gPt/kWe rated in stack
0.3 / 0.2 < 0.18gPt/kW for cell V < 0.67 Vin 50 cm2 cell at 150kPa inlet
PGM Total Loading mg PGM/cm2 of total MEA area
0.3 / 0.2 0.15 with current PtCoMn alloy(A/C = 0.05/0.10)
Durability under Load Cycling Hours, T < 80oCHours, T > 80oC
5000 / 50002000 / 5000
> 7000 hours in 50cm2 cellat 80/64/64oC
Mass Activity (150kPa H2/O2 80oC. 100% RH)
A/mg-Pt @ 900 mV, 150kPa O2
0.44 / 0.44 0.16 A/mg in 50 cm2 w/ PtCoMn 0.33A/mg in 50 cm2 with new PtxMy
Specific Activity (150 kPa H2/O2 at 80oC, 100% RH)
μ A/cm2-Pt @ 900 mV
720 / 720 2,100 for PtCoMn, 0.1mgPt/cm2
2,500 for new PtxMy , 0.1mgPt/cm2
Accel. Loss: 30,000 cycles, 0.7 –0.9V step, 30 s hold at 80/80/80oC
- mV at 0.8 A/cm2
% ECSA loss < 30mV
< 40% / 40 %~ 0 mV loss at 0.8 A/cm2
~ 0% loss ECSA
Accel. Loss: 200 hr hold @ 1.2 V at 95oC, H2/N2, 150kPa, 80% RH
- mV at 1.5 A/cm2
% ECSA loss< 30mV
< 40% / 40%+ 25mV gain at 1.5 A/cm2
~ - 17% loss ECSA
OCV hold without PEM failure under250/200 kPa H2/air, 90oC, 30%RH
Hours
mA/cm2
200< 20
900 – 1300 H2 Crossover < 20 mA/cm2,
F- ion release rate < 0.5 µg/cm2-day
Accel. Loss: 4,000 cycles 0.6 -1.2V, 20mV/sec, 95/95/95oC, 270kPa,H2/N2
ORR Specific Activ % ECSA loss
?? + 5% gain in mA/cm2Pt
- 30 % loss of cm2Pt / cm2
planar
Project Summary : Status Against DOE Targets – March, 2009
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
20
Project Summary: Overview for 2009Relevance: Critically focused on overcoming the three most critical barriers for fuel cell MEA development (A, B, C on Overview slide)
Approach: Builds on 12 year DOE/3M funded development of NSTF catalyst and MEA technology that fundamentally has higher specific activity, removes all durability issues with carbon supports, much reduced losses due to Pt dissolution and membrane chemical attack, with high volume manufacturing advantages.
Technical Accomplishments and Progress: In 50 cm2 cell tests, have exceeded the DOE 2015 targets for specific power density (gPt/kW), total PGM loadings, and multiple accelerated durability tests (including OCV hold and load cycling). Have demonstrated new alloys that approach the 0.44 A/mgPt mass activity target in 50 cm2 cells and exceed 0.8 A/mgPt in RDE measurements.
Technology Transfer/Collaborations: Extensive interactions with key partners has been productive in developing methods to increase catalyst activities and surface areas. Extensive interactions with a major systems integrator has been critical to validate performances and identify real world gaps and issues, while initial work with electrolyzer integrators offer technology assessment for H2 generation.
Proposed Future Research: Strongly focused on advancing NSTF MEA materials for improved water management with robust operating windows, and implementing increased mass activity and higher durability in practical catalysts.
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
21
Additional Slides
25
Multi-electrode NSTF Array
Pt-Content in Array (At.%)
50% 35%
E-11
Pt49.9Co37.4Zr
12.7
E-12
Pt47.3Co35Zr1
7.7
E-13
Pt40Co35Zr25
E-14
Pt33.8Co32.7Zr
33.5
E-15
Pt32.5Co28.6Zr
38.9
E-16
Pt35.8Co30Zr34.2
E-21
Pt52.1Co36.5Zr
11.4
E-22
Pt45.1Co36.9Zr
18
E-23
Pt39Co35.3Zr2
5.7
E-24
Pt33.4Co32.6Zr
34
E-25
Pt32Co30.1Zr3
7.9
E-26
Pt37.5Co29.2Zr33.3
E-31
Pt50.5Co33.2Zr
16.3
E-32
Pt44.7Co35Zr2
0.3
E-33
Pt39.2Co36.6Zr
24.2
E-34
Pt33.4Co32.8Zr
33.8
E-35
Pt35.1Co28.5Zr
36.4
E-36
no whiskers
-5.00E-03
-4.00E-03
-3.00E-03
-2.00E-03
-1.00E-03
0.00E+00
1.00E-03
2.00E-03
3.00E-03
4.00E-03
5.00E-03
0 0.2 0.4 0.6 0.8 1 1.2 1.4
Electrode Potential, V vs. NHE
Cur
rent
Den
sity
, A/c
m2
200 mV/s
100 mV/s
80 mV/s
50 mV/s
Pt-Zr NSTF
Pine Rotator
8” OD Crystallization Dish
JPL: Preparation and Characterization of NSTF-Coated Electrode Arraysusing novel rotating electrolyte approach
Composition Range on Electrode ArrayCo-sputtering of Alloy NSTF
Electrochemical Cell Electrochemical Surface Area
Glass SubstrateTi adhesion layer
Au current collector
Sputter targetSputter target
Zr Pt3CoGlass SubstrateTi adhesion layer
Au current collector
Sputter targetSputter target
Zr Pt3CoZr Pt3Co
C. C. Hays and S. R. Narayanan
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
26
10-6
-9
-8
-7
-6
-5
-4
-3
-2
-1
1
2 Current (Amps)
1.051.000.950.90
Volts (NHE)
E-11: I = -3.6e-6 Amps at 0.892V
E-16: I = -1.8e-6 Amps at 0.892VPt Thin Film: I = -0.81e-6 Amps at 0.892V
E-11,11-16-08 E16, 11-16-08
Polarization Curves for ORR with rotating electrolyte apparatus
-600x10-6
-500
-400
-300
-200
-100
0
100
OR
R C
urre
nt D
ensi
ty (0
.9V
, NH
E),
A/c
m2 )
50403020100ORR Scan Rate (mV/sec)
Potentiostatic (slow stir) Maximum Stir Rate (200-300 rpm?) Reduced Stir Rate (~0.25*Max Rate)
Scan Rate Measurements for ORR on PtCoZr NSTF
C. C. Hays and S. R. Narayanan
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
Limiting currents (not presented) are about three times less than RDE measured at Dalhousie on the same NSTF configuration at 400 rpm.
The current at 0.9 V at 50 mV/s is 3 – 4 times that measured at 1 mV/s.
JPL: Preparation and Characterization of NSTF-Coated Electrode Arraysusing novel rotating electrolyte approach
27
Technical Accomplishments – RDE ORR (0.9 v) Activity and E1/2 at 20oC from vs NSTF alloy type
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0.90
0.92
0.94
0.96
0.98
All 65 μgPt/cm2disk
1600 rpm, 20 mV/sec0.1M HClO4
RDE Activity Plots - graph 11, data 3
H
alf-W
ave
Pot
entia
l, E 1/
2 (V
)
20oC
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0.90
0.92
0.94
0.96
0.98
Hal
f-Wav
e P
oten
tial,
E 1/2 (
V)
All 65 μgPt/cm2disk
1600 rpm, 20 mV/sec0.1M HClO4
RDE Activity Plots - graph 12, data 3
60oc
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0
1
2
3
4
5
6
7
8
9
All 65 μgPt/cm2disk
1600 rpm, 20 mV/sec0.1M HClO4
DOE Target = 0.72
RDE Activity Plots - graph 9
Spe
cific
Act
ivity
at 9
00 m
V (m
A/c
m2 P
t)
20oC
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
DOE 2015 Target = 0.44 A/mg
RDE Activity Plots - graph 4, data 3
Mas
s A
ctiv
ity a
t 900
mV
(A/m
g Pt) 20oC
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
28
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
0.20
RDE Activity Plots - graph 3, data 3
M
ass
Act
ivity
at 9
50 m
V (A
/mg P
t)
20oC
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
RDE Activity Plots - graph 2, data 3
Mas
s A
ctiv
ity a
t 950
mV
(A/m
g Pt)
60oC
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
All 65 μgPt/cm2disk
1600 rpm, 20 mV/sec0.1M HClO4
RDE Activity Plots - graph 8, data 3
Spe
cific
Act
ivity
at 9
50 m
V (m
A/c
m2 Pt
)
60oC
NSTF Pt
Treated NSTF Pt
NSTF PtCoMn
Treated NSTF PtCoMn
NSTF PtNiFe
Treated NSTF PtNiFe
NSTF PtM
Treated NSTF PtM0.0
0.5
1.0
1.5
2.0
All 65 μgPt/cm2disk
1600 rpm, 20 mV/sec0.1M HClO4
RDE Activity Plots - graph 10
Spe
cific
Act
ivity
at 9
50 m
V (m
A/c
m2 Pt
)
20oC
Technical Accomplishments – RDE ORR Activity at 950 mV and 20 and 60 oC vs NSTF Alloy
Type
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
29
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.00.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Anode/Cathode: NSTF PtCoMn 0.05/0.10 mgPt/cm2 PEM: 3M 850 EW, 20 micron; GDL: 3M New
FC14654 760.DAT FC14654 760.DAT - HFR FC12969-939R, J FC12969-939R - HFR FC014693 575.RAW HFR
Anode/Cathode: NSTF PtCoMn 0.1/0.15 mgPt/cm2
PEM: 3M 850 EW, 35 micron; GDL: 3M 2975
Galvanodynamic ScansTcell = 80°C H2/air stoich = 2.0/2.5H2/air Inlet pressure = 200 kPaRelative Humidity = 67% GDS(0.02, 2, 10 step/dec, 180s/pt)Both MEA electrodes conditioned50 cm2 Quad serpentine cell
NSTF Base Line10/10/07A/C=0.10/0.15
Best of Class 01/22/09FC14654, FC14693A/C=0.05/0.10
Specifc Power Density Projections- graph 8
Cel
l Vol
tage
(V) a
nd H
FR (o
hm-c
m2 )
J (A/cm2)
200 kPa50mV gain at 2 A/cm2
28% reduction in impedance
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.00.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
FC12969-937R, V FC12969-937R, HFR FC14654-757, V FC14654-757, HFR FC014693-572, V FC014693-596, HFR
Best of Class 1/22/09FC14654, FC14693
Previous Best : A/C = NSTF PtCoMn 0.1/0.15 mgPt/cm2 PEM: 3M 850 EW, 35 micron; GDL: 3M 2975
New Best of Class: A/C = NSTF PtCoMn 0.05/0.10 mgPt/cm2 PEM: 3M 850 EW, 20 micron; GDL: 3M New
Specifc Power Density Projections- graph 6
Galvanodynamic ScansTcell/DP's = 80/68/68 °C H2/air stoich = 2.0/2.5H2/air Inlet pressure = 150 kPaGDS(0.02, 2, 10 step/dec, 180s/pt) 50 cm2 Quad serpentine cell
HFR
Cel
l Vol
tage
(V) a
nd H
FR (o
hm-c
m2 )
J (A/cm2)
150 kPa85mV gain at 2 A/cm2
34% reduction in impedance
GDS Polarization Curves
40% reduction in Pt loading20 vs 35 µm thick 3M PEMImproved 3M GDL
Improvement from:
Technical Accomplishments: higher power density, reduced loading
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
30
Baseline Best of Class MEA - Oct., 2007A/C Loading =0.1/0.15 mgPt/cm2
35 micron 3M PEMStd. 3M GDL
Baseline Best of Class MEA - Jan., 2009A/C Loading = 0.05/0.10 mgPt/cm2
20 micron 3M PEMNew 3M GDL
40% reduction in Pt loading40% reduction in mass transport over-potential at 2 A/cm2, 150kPa
0.1 10.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
MTO = 72 mV @ 2A/cm2
72 mV
0.02 2
HFR
70 mV/decadeTafel Slope
FC12969-graph18
Tcell/DP's = 80/68/68°C H2/air stoich = 2.0/2.5H2/air pressure = 7.5/7.5 psigGDS(0.02, 2, 10 step/dec, 180s/pt, 0.5V limit)50 cm2 Quad serpentine cell
E(V
), H
FR (o
hm-c
m2 ) a
nd E
IR-F
ree(V
)
Current Density (A/cm²)
FC12969-937R FC12969-937R, HFR, (ohm-cm²) FC12969-937R, IR-Free Cell Voltage, (volts)
Previous Best of Class New Best of Class
Technical Accomplishments: higher power density, reduced loading
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
31
48% reduction in specific power density at peak power40% reduction in Pt loadingExceeds DOE-2015 targets for Specific Power Density and total PGM loading
Inverse Specific Power Density200 kPa Inlet Pressure
Technical Accomplishments: higher power density, reduced loading
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.00.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
Galvanodynamic ScansTcell = 80°C H2/air stoich = 2.0/2.5H2/air Inlet pressure = 200 kPaRelative Humidity = 67% GDS(0.02, 2, 10 step/dec, 180s/pt)Both MEA electrodes conditioned50 cm2 Quad serpentine cell
New Best of Class: A/C = NSTF PtCoMn 0.05/0.10 mgPt/cm2 PEM: 3M 850 EW, 20 micron; GDL: 3M New
FC14654-760, Power Density, 200kPa FC14654-760, Voltage, 200kPa FC14693-575, Power Density, 200kPa FC14693-575, Voltage, 200kPa
Specifc Power Density Projections- graph 11
Cel
l Vol
tage
(V) a
nd P
ower
(W/c
m2 )
J (A/cm2)
Cell Voltage and Power200 kPa Inlet Pressures
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
0.55 0.60 0.65 0.70 0.75 0.800.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
DOE 2015 Target
Galvanodynamic ScansTcell/DP's = 80/68/68 °C H2/air stoich = 2.0/2.5H2/air Inlet pressure = 200 kPaGDS(0.02, 2, 10 step/dec, 180s/pt)Both MEA electrodes conditioned50 cm2 Quad serpentine cell
New Best of Class: A/C = NSTF PtCoMn 0.05/0.10 mgPt/cm2 PEM: 3M 850 EW, 20 micron; GDL: 3M New
FC14654-760FC14693-575
01/22/09
Previous Best of ClassFC12969-939R
10/05/07
Cell Voltage (V)
(Spe
cific
Pow
er D
ensi
ty)-1
(gPt
tota
l / k
W)
Specifc Power Density Projections- graph 7
Previous Best : A/C = NSTF PtCoMn 0.1/0.15 mgPt/cm2 PEM: 3M 850 EW, 35 micron; GDL: 3M 2975
32
Example Studyto Illustrate the Methodology
- Pt1-xZrx -
Tasks 1.1.2, 1.3, 2: Dalhousie/3M
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
33
0.00
0.06
0.12
0.18
0.24
0.30
0.36
• Constant Pt, ~75 nm planar equivalent (~0.15 mg/cm2)• Linear gradient out to ~ 40 atomic% Zr intimately mixed with the Pt
Incr
easi
ng Z
r
Constant Pt
Dashed rectangle shows region measured with microprobe. Circles show positions of FC channels 100 120 140 160
Radial distance from center of table (mm)
0.10
0.15
0.20
0.25
0.30
Load
ing
(mg/
cm2 )
100 120 140 160Radial distance from center of table (mm)
0.00
0.10
0.20
0.30
0.40
x in
Pt 1-
xZr x
x = 3.54 x 10-3 D - 0.261
Example of Pt1-xZrx Binary Study: Sputtering Details
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
34
14 days, 80°C, 0.5 M H2SO4
0 0.1 0.2 0.3 0.4Predicted x in Pt1-xZrx
0
0.1
0.2
0.3
0.4
Mea
sure
d x
in P
t 1-xZ
r x
Pre-corrosion testingPost-corrosion testing
Example of Pt1-xZrx Binary Study: Corrosion Testing, XRD Data
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
30 40 50 60 70 80 902θ Scattering Angle (°)
Inte
nsity
(cou
nts)
0.05
0.10
0.15
0.20
0.25
0.30
0.35
xin
Pt1-x Zrx
Extract grain size and lattice parameters as a function of composition
35
Incr
easi
ng Z
r A B C D E F G H8
7
6
5
4
3
2
1
Before break-in conditioning
After break-in conditioning
0 250 500
-0.4
0.4
0 250 500 0 250 500 0 250 500Cell Potential (mV)
0 250 500 0 250 500 0 250 500 0 250 500
-0.4
0.4-0.4
0.4-0.4
0.4
Cur
rent
Den
sity
(mA
/cm
2 )
-0.4
0.4-0.4
0.4-0.4
0.4-0.4
0.4
0 250 500
-0.4
0.4
0 250 500 0 250 500 0 250 500Cell Potential (mV)
0 250 500 0 250 500 0 250 500 0 250 500
-0.4
0.4-0.4
0.4-0.4
0.4
Cur
rent
Den
sity
(mA
/cm
2 )
-0.4
0.4-0.4
0.4-0.4
0.4-0.4
0.4
Example of Pt1-xZrx Binary Study: Cyclic Voltammetry
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
36
Incr
easi
ng Z
r
A B C D E F G H8
7
6
5
4
3
2
1
After 10s at potential
After 1 min at potential
0 5001000500
750
0 5001000 0 5001000 0 5001000Current Density (mA/cm2)
0 5001000 0 5001000 0 5001000 0 5001000
500
750
500
750
500
750
Cha
nnel
Pot
entia
l (m
V)
500
750
500
750
500
750
500
750
1000
0 5001000500
750
0 5001000 0 5001000 0 5001000Current Density (mA/cm2)
0 5001000 0 5001000 0 5001000 0 5001000
500
750
500
750
500
750
Cha
nnel
Pot
entia
l (m
V)
500
750
500
750
500
750
500
750
1000
Example of Pt1-xZrx Binary Study: ORR performance under O2
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
37
0 0.1 0.2 0.3x in Pt1-xZrx
0
50
100
150
200
250
300
iR-c
orre
cted
Cur
rent
Den
sity
at 8
00m
V (m
A/c
m2 )
0 0.1 0.2 0.3 0.4x in Pt1-xZrx
After holding for 10s After holding for 1 min
Example of Pt1-xZrx Binary Study: ORR performance under O2
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
38
0 0.1 0.2 0.3 0.4x in Pt1-xZrx
0
50
100
150
200
250
300iR
-cor
rect
ed c
urre
nt d
ensi
ty a
t 800
mV
(mA
/cm
2 )
Before Durability TestingAfter Durability Testing
Example of Pt1-xZrx Binary Study: ORR specific activity
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
39
0 0.1 0.2 0.3x in Pt1-xZrx
5
10
15
20
25
30Sp
ecifi
c C
urre
nt D
ensi
ty a
t 800
mV
(mA
/cm
2 EC)
0 0.1 0.2 0.3 0.4x in Pt1-xZrx
After holding for 10s After holding for 1 min
Example of Pt1-xZrx Binary Study: ORR specific activity
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
40
0 125 2500
4080
0 125 250 0 125 250 0 125 250Current Density (mA/cm2)
0 125 250 0 125 250 0 125 250 0 125 250
040800
40800
4080
Cha
nnel
Pot
entia
l (m
V)
040800
40800
40800
4080
Incr
easi
ng Z
r
A B C D E F G H8
7
6
5
4
3
2
1
Example of Pt1-xZrx Binary Study:H2 oxidation performance
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
41
0 400 800-1012
0 400 8000 400 8000 400 800
Cell Potential (mV)
0 400 8000 400 8000 400 8000 400 800
-1012-1012-1012-1012
Cur
rent
Den
sity
(mA
/cm
2 )
-1012-1012-1012
A B C D E F G H8
7
6
5
4
3
2
1
Incr
easi
ng Z
r
75°C, 100% RH
Example of Pt1-xZrx Binary Study: Crossover determination
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
42
0 20 40 60Channel Number
0
0.4
0.8
1.2
1.6C
ross
over
Cur
rent
Den
sity
(mA
/cm
2 )
Example of Pt1-xZrx Binary Study: Crossover determination
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
43
0 250 500
-0.4
0.4
0 250 500 0 250 500 0 250 500Cell Potential (mV)
0 250 500 0 250 500 0 250 500 0 250 500
-0.4
0.4-0.4
0.4-0.4
0.4
Cur
rent
Den
sity
(mA
/cm
2 )
-0.4
0.4-0.4
0.4-0.4
0.4-0.4
0.4A B C D E F G H
8
7
6
5
4
3
2
10 250 500
-0.4
0.4
0 250 500 0 250 500 0 250 500Cell Potential (mV)
0 250 500 0 250 500 0 250 500 0 250 500
-0.4
0.4-0.4
0.4-0.4
0.4
Cur
rent
Den
sity
(mA
/cm
2 )
-0.4
0.4-0.4
0.4-0.4
0.4-0.4
0.4
Incr
easi
ng Z
r
Before CV Cycling After CV Cycling (3000 cycles)
High Voltage CV Cycling 600 – 1200 mV cycling
Example of Pt1-xZrx Binary Study: Durability testing
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22