1 Advanced Cathode Catalysts and Supports for PEM Fuel Cells Mark K. Debe 3M Company May 20, 2009 Project ID: FC_17_Debe This presentation does not contain any proprietary, confidential, or otherwise restricted information 2009 DOE Hydrogen Program Review
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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
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
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
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
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
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
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.)
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.
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
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
Technical Accomplishments: higher power density, reduced loading
3M Advanced Cathode Catalysts ……………………... 2009 DOE Hydrogen Program Review, May 18 - 22
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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