1

Development of Ultra-low Platinum Alloy Cathode Catalyst for PEM Fuel Cells

P. I.: Branko N. Popov Center for Electrochemical Engineering

University of South Carolina Columbia SC 29208.

This presentation does not contain any proprietary, confidential, or otherwise restricted information

2013 DOE Hydrogen and Fuel Cells Program Review

Project ID # FC088

May 16, 2013

2

Overview Timeline

Start date: June 2010 End date: Sep 2013(Phase I) (No-cost Extension Apr-Sep 2013) : March 2015 (Phase II) Percent complete: 65%

Partners Yonsei University (YU), S. Korea Hyundai Motor Company (HMC),

S. Korea (Funding ended in Dec 2011; will resume in Phase II)

Budget Total project funding

DOE share: $ 4,400,000 Phase-I: $2,750,000 Phase-II: $1,650,000

Contractor share: $1,100,000 Phase-I: $687,500 Phase-II: $412,500

Funding Received till March 2013: $1,896,403 Expected Funding for Phase-I: $853,597 (Until 09/30/2013)

Barriers Catalyst performance Catalyst durability Scale-up synthesis procedures

Project Lead University of South Carolina (USC)

Additional Interactions Rudiger Laufhutte (Univ. Illinois) Dr. JoAn Hudson (Clemson University)

Electrocatalyst/MEA 2017 Targets

PGM Loading (mg/cm2) 0.125

PGM Total Content (g/kW) 0.18

Mass Activity (A/mgPt) 0.44

ECSA Loss after 30 k Cycles (Catalyst Stability) (%)

≤ 40

ECSA Loss after 400 h (Support Stability) (%)

≤ 40

DOE Technical Targets

3

Objectives: Development of high performance, low cost and durable cathode catalyst and support able to meet the 2017 DOE targets. Approach: Optimization studies of carbon composite catalyst (CCC) support. (USC) Development of a process for the in-house synthesis of carbon nanocage (CNC) (USC and YU) Development of advanced hybrid catalyst based on CCC support and Pt [low Pt-alloy loading

catalyst]. (USC) Development of carbon nanocage (CNC) supported Pt-alloy catalyst (Pt-alloy/CNC). (USC & YU) Development of high volume procedures for the synthesis of promising catalyst. (USC & YU) Primary Focus for Past Year: Performance evaluation of second generation CCC support. (USC)

Structural and physical characterization Catalytic activity of CCC250 and CCC380 CCC supports

Performance evaluation of USC Pt/CCC catalysts. 40% Pt/CCC380 and 35% Pt/CCC250 catalysts

Evaluation of different strategies for the optimization of second generation hybrid cathode catalyst (HCC, HCC = PtCo/CCCx, X=250 or 380 m2/g) with total loadings of 0.2 mgPt /cm2 /MEA. (USC) (CCC supports having BET surface area between 250 and 380 m2/g) Initial and durability of kinetic mass activities. Initial and durability of high current density performance in H2-air.

HCC250 and HCC380 catalysts Study the mass activity, durability and power density as a function of catalyst composition

Performance evaluation of Pt-alloy/CNC catalyst activity and durability with total loadings of ~0.2 mgPt /cm2 /MEA. (YU)

Relevance and Approach

4

Project Timeline and Milestones*

Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 9/1/10 2/28/13

Budget Period 1 (2.5 years)

Task 1: CCC support

Task 2: Development of HCC catalysts

No Cost Extension Period** 3/1/13 Q11 Q12 Q13

Task 3: Development of Pt-alloy/CNC catalysts

Task 4: Catalysts’ activity and durability studies

Task 5: Development of non-carbon supported catalysts

Task 6: High current density performance under H2-air

Task 7: Durability studies under H2-air

Task 8: Scale-up synthesis of promising catalysts

End of task.

Go-No-Go decision for the selection of 2 promising catalysts for further evaluation studies. *Milestones are explained in slides 5& 6

Go-No-Go decision for the selection of 2 promising catalysts with high power density, mass activity and durability.

9/30/13

**No-cost extension (6 months) requested to complete Task 7

Characteristic Units 2017 Targets Status

Mass activity (80 oC, 100% RH, 150 kPaabs.)

A/mgPt @ 0.9 ViR-free 0.44 0.43 (USC Pt2Ni1/CCC<600 ) 0.38 (USC HCC250) 0.37 (USC HCCC380) 0.44 (YU Pt2Ni1/CNC) (Milestone 2)

Catalyst durability (30,000 cycles 0.6-1.0 V, 50 mV/s, 80/80/80, 100 kPaabs., H2/N2)

% Mass activity loss % ECSA loss

mV loss @ 0.8 A/cm2

≤40% ≤40%

≤ 30 mV

47% (mass activity) & 15% (ECSA) for USC HCC250 53 mV loss at 0.8A/cm2 under H2-air for USC HCC250 46% (mass activity) & 19% (ECSA) for USC HCC380 53% (mass activity) & 27.8% (ECSA) for USC Pt2Ni1/CCC<600) 31.8% (mass activity) & 26.3% (ECSA) for YU Pt2Ni1/CNC (Milestone 3)

Support durability (1.2 V for 400 h at 80 oC, H2-N2, 150 kPaabs. 100% RH)

% Mass activity loss % ECSA loss

mV loss @ 0.8 A/cm2

≤40% ≤40%

≤ 30 mV

50% mass activity loss and 42% ECSA loss for USC HCC250 29 mV loss at 0.8 A/cm2 under H2-air for USC HCC250 47% mass activity loss and 64% ECSA loss for the USC Pt/CCC250 118 mV loss at 0.8 A/cm2 under H2-air for the USC Pt/CCC250 47.7% mass activity loss and 42.7% ECSA loss For YU Pt2Ni1/CNC (NL) (Milestone 3)

PGM total loading mgPt/cm2 0.125 0.15-0.2 mgcatalyst/cm2 with USC Pt/CCC250, HCC250, Pt2Ni1/CCC<600, Pt1Co1/CCC380 and 0.19 mgcatalyst/cm2 with YU Pt2Ni1/CNC

PGM total content gPt/kW (rated) 0.18 0.39 (33% Pt1Co1/CCC380) – USC 0.36 (35% Pt/CCC250 and HCC250) – USC 0.34 (46% Pt2Ni/CCC<600) - USC 0.37 (50% Pt2Ni/CNC-NL) – YU

5

Technical Accomplishments Milestone Progress (Apr ‘12 – Mar ‘13)

Carbon composite support was synthesized with onset potential for oxygen reduction closer to 0.9 V vs. SHE and less than 2.5% H2O2 production. Milestone 1.

6

Technical Accomplishments Milestone Progress (Apr ‘12 – Mar ‘13)

Phase-II Task 1-4. Optimization studies of selected catalysts (HCC and Pt-alloy/CNC).

a) Initial and durability of mass activity b) Support durability c) Initial and durability of high current performance under H2-air.

Task 8. Optimization of scale-up synthesis procedure.

Task 9. Short-stack testing

a) Construction of short-stack (up to 10 cells, 50 cm2) using two selected catalysts b) Durability of high current performance under H2-air c) Catalyst down selection Criteria: Durability under cycling transportation conditions at 80 oC for 5000 hours.

Deliverable: Fuel cell and short stack will be constructed using the most promising catalyst and supplied to a DOE designated site.

Milestone 4: Dec 2012: Initial high current density performance in H2-air (80 oC, 100% / 40% RH, 150 kPaabs. outlet pressure, 1.5/1.8 stoic.). (Task 6 and 7) Status: Achieved 1.25 and 1.04 A/cm2 at 0.58 ViR-free for the Pt/CCC250 and HCC380 catalysts, respectively. Milestone 5: Sep 2013: Scale-up synthesis and durability of promising catalysts with optimum high current density performance in H2/air. (Task 8) Status: Scale-up synthesis of HCC and Pt2Ni/CNC: On going. The catalyst durability studies under high current region in H2-air for USC HCC and Pt2Ni/CNC catalysts started in March 2012.

• Surface modification of carbon black with:

(i) O-containing group (ii) N-containing group • Pyrolysis

• “Metal-catalyzed pyrolysis” (Fe or Co) to increase the number of active sites by leaching

Technical Accomplishments (I. Support Development) Progress in the Synthesis of CCC Supports (Apr ‘12 – Mar ‘13)

7

CCC,25℃ CCC,400℃, 1h 5 ℃/min Pyrolysis

(900-1500 oC) 5 ℃/min

HRTEM

CCC380

CCC250

HIGHLIGHT: XRD: The degree of graphitization increases with the increase in the pyrolysis temperature. Presence of Co particles are confirmed. BET: The BET surface area decreases with the increase in the pyrolysis temperature. HRTEM: Graphitic carbon containing carbon nano fibers/tubes are formed during pyrolysis between 1100 and 1500 oC in the presence of cobalt. Milestone 1

Pyrolysis Temp.

(oC)

BET surface area (m2/g)

Co % (ICP)

900 380 -

1100 250 0.66

1500 160 1.02

XRD

0 20 40 60 80 100

CCC 1500oC

CCC 1300oC

CCC 1100oC

CCC 900oC

Inte

nsity

(a.

u)

2 theta

CCC150

Scale bar 20 nm

Technical Accomplishments (I. Support Development) Progress in Electrochemical Performance of CCC Supports (RRDE Studies) (Apr ’12 – Mar ’13)

HIGHLIGHT: • Nanostructured fibers of graphitic carbon was formed as a result of

metal-catalyzed pyrolysis (HRTEM). • The degree of graphitization increases as the pyrolysis temperature

increased (XRD) • The onset potential for ORR increases when the as received carbon is

subjected to various surface modifications. • The carbon composite catalyst (curve f) showed an onset potential of

0.9 VRHE and well-defined kinetic and mass transfer regions. • The CCC-4 exhibits oxygen reduction to water via four-electron

transfer with <2% H2O2 production (above 0.2 V vs. NHE). Milestone 1

0 0.2 0.4 0.6 0.80

10

20

30

40

(d)

(c)

(b)(a)

% H

2O2 /

-

Disk Potential / V(NHE)

(f)

(c)

(e)

(d)

HRTEM ORR – RRDE Studies H2O2 production – RRDE Studies

0 20 40 60 80 1000

500

1000

1500

2000

2500

3000

3500

1100 oC

800 oC1000 oC

Inte

nsity

(cps

)

2θ (deg.)

CCC400(800 oC) CCC380 (900 oC) CCC350 (1000 oC) CCC250 (1100 oC)

900 oC

XRD

8

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9-5

-4

-3

-2

-1

0

(c)(d)

(e)

Curre

nt (m

A)

Potential (V) vs. NHE

(a) Carbon(b) Oxidized carbon(c) CCC-1(d) CCC-2(e) CCC-3(f) CCC-4 0.1 M HClO4

5 mV/s1600 rpm100 µg/cm2

(f)

HIGHLIGHT: •Normal heat-treatment results in 8-10 nm particles. The new process yields in uniform particle size distribution with ~3.4 nm Pt-alloy particles. •The alloy formation is confirmed from the shift in the Pt (220) peak and the particle size is ~3.5 nm. • The ORR activity of the un-leached catalyst (0.2 mA) is drastically increased after leaching (1.2 mA). The onset potential for ORR is 1.0 V for the Pt1Co1/CCC250 (leached) catalyst. • Current research is focused on the control of Pt/Co ratio and heat-treatment temperature which will result in highly active catalyst without the leaching step.

30 40 50 60 70 80 900

400

800

1200

1600

2000

2400

40% Pt1Co1/CCC (leached) 3.5nm

40%Pt/CCC fresh 2.2 nm

Inte

nsity

(a.u

)

2θ (deg.)

40% Pt1Co1/CCC (unleached)

Technical Accomplishments (II. Catalyst Development) Progress in the Synthesis of Pt/CCC and HCC Catalysts (Apr ’12 – Mar ’13)

9

0.2 0.4 0.6 0.8 1.0 1.2-0.0018

-0.0016

-0.0014

-0.0012

-0.0010

-0.0008

-0.0006

-0.0004

-0.0002

0.0000

40% Pt/CCC 40% PtCo/CCC (unleached) 40% PtCo/CCC (leached)

Curre

nt (A

)

Potential vs RHE (V)

0.1 M HClO4

5 Mv/S20 µg Pt/cm2

XRD

ORR

20 30 40 50 60 70 80 90

40% Pt1Co1/CCC380 (leached) 3.5nm 33% Pt1Co1/CCC380 (leached) 3.8nm 35% Pt2Ni/CCC250 4.0nm 40% Pt1Co1/CCC250 3.3nm

Rela

tive

Inte

nsity

(a.u

.)

2 θ (deg.)

XRD

Pt/CCC Transition metal salt

impregnation

900℃ normal heat –treatment

900℃ modified heat –treatment

Transition metal salt

impregnation

Modified heat-treated Pt-

alloy/CCC (HCC)

Normal heat-treatment

Pt-alloy/CCC (HCC)

HCC = Different Pt alloy catalysts

HIGHLIGHT: (Status against 2017 DOE targets) • HCC250 satisfies the 2017 DOE target of ≤40% mass activity and ECSA loss

after 30 k cycles (0.6-0.925 V). (Milestone 3)

Technical Accomplishments (III. Catalyst Durability) Progress in Catalyst Durability Studies (0.6-0.925 V Cycling) Apr ’12 – Mar ’13)

0.01 0.1 1 100.80

0.82

0.84

0.86

0.88

0.90

0.92

0.94

0.96

0.98

0.2

H2/O2 (2/9.5 stoic.)80 oC, 100% RH150 kPaabs.

Initial 30K cycles

iR-c

orre

cted

Cel

l Vol

tage

(V)

Mass Activity (A mg-1)

0.373

Catalyst: HCC380

46% loss

0.0 0.1 0.2 0.3 0.4 0.5 0.6

-0.10

-0.08

-0.06

-0.04

-0.02

0.00

0.02

0.04H2/N2 (75/200 cc/min)80 oC. 100% RH

initial 30K cycles

Cur

rent

(A)

Potential (V)

Catalyst: HCC380

19% loss

ECSA Loss Mass activity Loss

0.1 10.80

0.82

0.84

0.86

0.88

0.90

0.92

0.94

0.96

iR-c

orre

cted

Cel

l Vol

tage

Mass Activity (A mg-1)

initial 30K cycles

0.38

0.25

H2/O2 (2/9.5 stoic.)80 oC, 100% RH150 kPaabs.

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7-0.06

-0.05

-0.04

-0.03

-0.02

-0.01

0.00

0.01

0.02

0.03

Cur

rent

(A)

Potential (V)

Initial 30 k cycles

Catalyst: HCC250

Catalyst: HCC250

34% loss 6% loss

DOE Accelerated Stress Test Protocol 0.6 ~ 0.925 V, 50mV/s, 30,000 cycle, H2/N2 (200/75 sccm), 80oC, 100 % RH, single cell 25cm2 Pt mass activity : H2/O2, 2.0/9.5 stoic, 100% RH, 80oC, 150 kPa

HCC380 Mass Activity@0.9V

(A/mg)

Loss (%)

Initial 0.37 -

30 k cycles 0.2 46%

HCC380 ECSA (m2/g)

Loss (%)

Initial 21.4 -

30 k cycles 17.4 19%

HCC250 Mass Activity@0.9V

(A/mgPt)

Loss (%)

Initial 0.38 -

30K cycles 0.25 34

HCC250 ECSA (m2/gPt)

Loss (%)

Initial 22.6 -

30K cycles 21.24 6

10

HIGHLIGHT: (Status against 2017 DOE targets) • HCC250 and HCC380 catalysts show mass activity loss of 34 and 46%, respectively. 46% Pt/C shows 68% mass activity loss. The 2017 DOE target is ≤40% loss after 30 k cycles. (Milestone 3) • HCC250 and HCC380 catalysts show ECSA loss of 6 and 19%, respectively. The 46% Pt/C shows 80% ECSA loss. •USC HCC catalysts satisfy the 2017 DOE target of ≤40% ECSA loss after 30 k cycles. (Milestone 3)

11

Technical Accomplishments (III. Catalyst Durability) Progress in Catalyst Durability Studies (0.6-0.925 V Cycling) Apr ’12 – Mar ‘13

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

46% Pt/CHCC250

Mas

s ac

tivity

(A/m

-1 Pt)

0.37 0.38

0.19

0.06

0.2

0.2546% 34%46%

68%

HCC380

0

5

10

15

20

25

30

35

40

80% loss6% loss

46% Pt/CHCC250

ECSA

(m2 /g

Pt)

21.4

17.4

22.621.2

39.2

7.7

HCC380

19% loss

Comparison Mass activity loss of HCC Catalysts Comparison of ECSA loss of HCC Catalysts

Catalysts Support BET (m2/g)

Particle size (nm)

Initial mass activity (A/mgPt)

Mass activity loss (%)

46% Pt/C HCC380 HCC250

- 380 250

2.2 3.5 4.0

0.19 0.37 0.38

68.0 46.0 34.0

HIGHLIGHT: • HCC250 satisfies the 2017 DOE target of ≤40% mass activity and ECSA loss

after 30 k cycles (0.6-0.925 V). (Milestone 3)

HIGHLIGHT: Status against 2017 DOE targets • USC HCC250 catalyst shows 47% mass activity loss (2017 DOE target is ≤40%) and 15% ECSA loss (2017 DOE target is ≤40%) after 30 k cycles between 0.6 and 1.0 V. (Milestone 3)

12

0.1 10.78

0.80

0.82

0.84

0.86

0.88

0.90

0.92

0.94

0.96

0.38

0.2

iR-c

orre

cted

Cel

l Vol

tage

Mass Activity (A mg-1)

initial 30K cycles

H2/O2 (2/9.5 stoic.)80 oC, 100% RH150 kPaabs.

Mass Activity@0.9V (A/mg)

Loss (%)

Initial 0.38 -

30K cycles 0.20 47%

Technical Accomplishments (III. Catalyst Durability) Progress in Catalyst Durability Studies (0.6-1.0 V Cycling) Apr ’12 – Mar ‘13

Catalyst: HCC250

DOE Accelerated Stress Test Protocol 0.6 ~ 1.0 V, 50mV/s, 30,000 cycle, H2/N2 80oC, 100 % RH, single cell 25cm2 Catalyst : HCC250 Pt mass activity : H2/O2, 2.0/9.5 stoic, 100% RH, 80oC, 150 kPa

0.0 0.1 0.2 0.3 0.4 0.5 0.6-0.4

-0.3

-0.2

-0.1

0.0

0.1

Initial 30 k cycle

Curre

nt (A

)

Potential vs RHE (V)ECSA (m2/gPt) Loss

(%)

Initial 23.2 -

30K cycles 19.8 15

Mass activity loss of HCC250 ECSA loss of HCC250

Catalyst: HCC250

47% loss 15% loss

Technical Accomplishments (III. Catalyst Durability) Progress in Catalyst Durability Studies: HCC250 (0.6-1.0 V Cycling) Apr ’12 – Mar ‘13

0 200 400 600 800 1000 1200 1400 16000.00.10.20.30.40.50.60.70.80.91.0

0.561 V

0.607 V

80 oC, 40% RH, 150 kPa abs.Anode: 46% Pt/C (0.1 mg/cm2)Cathode: USC catalysts (0.1 mgPt/cm2)Membrane: Nafion NRE 212

iR-c

orre

cted

Cel

l Vol

tage

(V)

Current Density (mA cm-2)

Initial (1.5/1.8) 30K (1.5/1.8)

HIGHLIGHT: (Status against 2017 DOE targets) •The iR-corrected cell voltage loss at 800 mA/cm2 (1.5/1.8 stoic.) is 46mV (from 607mV to 561mV). • The cell voltage loss at 800 mA/cm2 (1.5/1.8 stoic.) is 53 mV (from 522 mV to 469 mV) against the 2017 DOE target of 30 mV loss after 30 k cycles. • The 46% Pt/C shows 237 mV loss after 20 k cycles at 0.8 A/cm2. (Milestone 3)

H2-air Fuel Cell Performance of HCC250

0 200 400 600 800 1000 1200 1400 16000.00.10.20.30.40.50.60.70.80.91.0

0.469 V

0.522 V

80 oC, 40% RH, 150 kPa abs.Anode: 46% Pt/C (0.1 mg/cm2)Cathode: USC catalyst (0.1 mgPt/cm2)Membrane: Nafion NRE 212

Cell V

olta

ge (V

)

Current Density (mA cm-2)

Initial (1.5/1.8) 30K (1.5/1.8)

13

DOE Accelerated Stress Test Protocol 0.6 ~ 1.0 V, 50mV/s, 30,000 cycle, H2/N2, 80oC, 100 % RH, single cell 25cm2 Catalyst : HCC250 Polarization : H2/air, 1.5/1.8 stoic, 40% RH, 59oC, 150 kPa

HCC250 HCC250

46 mV loss (iR-free) 53 mV loss

Catalysts Cell voltage loss after cycling (mV)

HCC250 53 (30 k)

46% Pt/C 237 (20 k) (Not shown)

Nafion is a registered trademark of E. I. duPont de Nemours & Company.

0 500 1000 1500 2000 2500 30000.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

H2/O2 (750/750 sccm)80oC, 100%RHno back pressure

40% Pt/CCC 35% Pt/CCC

Current Density (mA cm-2)

iR-c

orre

cted

Cel

l vol

tage

(V)

Technical Accomplishments Progress in Initial Performance Evaluation of Pt/CCC250 Catalysts (Apr ’12 – Mar ’13)

HIGHLIGHT: • The Pt/CCC250 catalysts show 1.25 and 1.3 A/cm2 current density at 0.58 ViR-free at cathodic stoics of 1.8 and 2, respectively. • The better fuel cell performance is due to the support purification process developed at USC to remove the amorphous carbon to obtain purified graphitic carbon support. Milestone 4 (Initial high current performance under H2/air)

0 200 400 600 800 1000 1200 1400 1600 18000.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

H2/Air (50/150 sccm)59oC, 40%RH150kPa back pressure

Current Density (mA cm-2)iR

-cor

rect

ed C

ell v

olta

ge (V

)

40% Pt/CCC (1.5/1.8) 40% Pt/CCC (1.5/2.0) 35% Pt/CCC (1.5/1.8) 35% Pt/CCC (1.5/2.0)

0.58V

H2-O2 Fuel Cell Performance Pt/CCC250 H2-air Fuel Cell Performance of Pt/CCC250

14 0 500 1000 1500 2000 2500 3000

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

H2/O2 (750/750 sccm)80oC, 100%RHno back pressure

40% Pt/CCC 35% Pt/CCC

Current Density (mA cm-2)

Cell v

olta

ge (V

)

0 200 400 600 800 1000 1200 1400 1600 1800

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

H2/Air (50/150 sccm)59oC, 40%RH150kPa back pressure

Current Density (mA cm-2)

Cell v

olta

ge (V

) 40% Pt/CCC (1.5/1.8) 40% Pt/CCC (1.5/2.0) 35% Pt/CCC (1.5/1.8) 35% Pt/CCC (1.5/2.0)

0.58V

Pt/CCC250 Pt/CCC250

Pt/CCC250 Pt/CCC250

Technical Accomplishments (IV. Support Durability) Progress in Support Stability Studies at 1.2 V Potential Holding (Apr ’12 – Mar ’13)

1. Support Stability Studies of 40% Pt/CCC250

0 400 800 1200 1600

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

iR-c

orre

cted

Cel

l Vol

tage

(V)

Current Density (mA cm-2)

Initial 120h 400h

H2/air : 1.5/1.8 (50/150 CC/min)150 KPa backpressure59oC, 40% RH

0.673 V

0.543 V

HIGHLIGHT: (Status against 2017 DOE targets) •The mass activity decreases from 0.227 to 0.12 A/mg (47.1% mass activity loss) after 400 h. •At 800 mA/cm2, the iR-cell voltage loss is 130 mV (from 673mV to 543mV) after 400 h potential holding at 1.2 V. • At 800 mA/cm2, the cell voltage loss is 118 mV (from 584 mV to 466 mV) after 400 h potential holding at 1.2 V. (Milestone 3)

Mass Activity Loss of Pt/CCC250 H2-air Performance of Pt/CCC250

0 400 800 1200 16000.00.10.20.30.40.50.60.70.80.91.0

Cell V

olta

ge (V

)

Current Density (mA cm-2)

Initial 120h 400h

H2/air : 50/150 cc/min150 KPa backpressure59oC, 40% RH

0.584 V

0.466

0.01 0.1 1 100.840.850.860.870.880.890.900.910.920.930.94

Mass activity (A mgPt-1)

iR-c

orre

cted

Cel

l Vol

tage

(V)

H2/O2 : 77/166 cc/minStoic ratio : 2/9.5150 KPa backpressure80oC, 100% RH

Initial 160h 400h

0.227

0.180.12

15

DOE Test Protocol Hold at 1.2V for 24 h, H2/N2 80oC, 150 kPa, 100 % RH, single cell 25cm2 Catalyst : USC Pt/CCC250 Polarization : H2/air, 1.5/1.8 stoic, 40% RH, 59oC, 150 kPa Pt mass activity : H2/O2, 2.0/9.5 stoic, 100% RH, 80oC, 150 kPa

40% Pt/CCC250

40% Pt/CCC250

40% Pt/CCC250

47% loss 130 mV loss

118 mV loss

Technical Accomplishments (IV. Support Durability) Progress in Support Stability Studies at 1.2 V Potential Holding (Apr ’12 – Mar ’13)

2. Support Stability Studies of HCC250

0 200 400 600 800 1000 12000.10.20.30.40.50.60.70.80.91.0

iR-c

orre

cted

Cel

l Vol

tage

(V)

Current Density (mA/cm2)

H2/air : 50/150 cc/minStoic ratio:1.5/1.8150 KPa backpressure59oC, 40% RH

Initial 400h

0.644 V

0.615 V

HIGHLIGHT: (Status against 2017 DOE targets) •The mass activity decreases from 0.38 to 0.19 A/mg after 400 h potential holding at 1.2 V (50% mass activity loss). •The potential loss is 29 mV (iR-corrected) after 400 h potential holding. • The cell potential loss is 29 mV after 400 h potential holding against the 2017 DOE target of 30 mV loss after 400 h. (Milestone 3)

Mass Activity Loss of HCC250 H2-air Performance of HCC250

0 200 400 600 800 1000 12000.10.20.30.40.50.60.70.80.91.0

Initial 400h

Cel

l Vol

tage

(V)

Current Density (mA/cm2)

H2/air : 50/150 cc/minStoic ratio:1.5/1.8150 KPa backpressure59oC, 40% RH

0.549 V

0.520 V

16

DOE Test Protocol Hold at 1.2V for 24 h, H2/N2 80oC, 150 kPa, 100 % RH, single cell 25cm2 Catalyst : USC HCC250 Polarization : H2/air, 1.5/1.8 stoic, 40% RH, 59oC, 150 kPa Pt mass activity : H2/O2, 2.0/9.5 stoic, 100% RH, 80oC, 150 kPa

0.01 0.1 1 100.86

0.87

0.88

0.89

0.90

0.91

0.92

0.93

0.94 Initial 220h 400h

H2/O2 : 77/166 cc/minStoic ratio : 2/9.5150 KPa backpressure80oC, 100% RH

iR-c

orre

cted

Cel

l Vol

tage

(V)

Mass Activity (A/mg)

0.22

0.380.19

50% loss

HCC250

HCC250

HCC250

29 mV loss

29 mV loss

HIGHLIGHT: (Status against 2017 DOE targets) • HCC250 catalyst shows 47% mass activity loss and 15% ECSA loss after 30 k cycles between 0.6 and 1.0 V. The 2017 DOE target is ≤40% loss of mass activity and ECSA after 30 k cycles. The potential loss at 800 mA/cm2 (1.5/1.8 stoic.) is 53 mV for the HCC250 against 2017 DOE target of 30 mV after 30 k cycles. •The mass activity loss is 50% and the potential loss at 800 mA/cm2 is 29 mV after 400 h potential holding at 1.2 V for the HCC250 catalyst. The 2017 DOE targets are ≤40% mass activity loss and 30 mV potential loss after 400 h.

17

Technical Accomplishments (IV. Support Durability) Progress Against DOE 2017 Targets for Pt/CCC250 and HCC250 Catalysts

Catalyst Particle size (nm)

Mass activity (A/mgPt) ECSA (m2/g) Cell voltage loss at 800 MA/cm2 (mV)

Initial 30 k Initial 30 k Cell voltage Cell voltage (iR-free)

HCC250 4.0 0.38 0.2 (47% loss) 23.2 19.8

(15% loss) 53 mV 46 mV

Catalyst Durability Test (Potential Cycling between 0.6 and1.0 V) (Milestone 3)

Catalyst Particle size (nm)

Mass activity (A/mgPt) ECSA (m2/g) Cell voltage loss at 800 MA/cm2 (mV)

Initial 400 h Initial 400 h Cell voltage Cell voltage (iR-free)

HCC250

Pt/CCC250

4.0

2.5

0.38

0.227

0.19 (50% loss)

0.12

(47% loss)

21.3

59.4

16.2 (42% loss)

21.3

(64% loss)

29 mV

118 mV

29 mV

130 mV

Support Stability Test (Potential Holding at 1.2 V) (Milestone 3)

Sep 2013: GO/NO-GO decision for Milestones 3, 4 and 5 Criteria: Selection of two most promising catalysts with (i) high kinetic mass activity, (ii) <40% loss of initial catalytic activity after 30 k cycles, (iii) initial high current density performance of at least 1.5 A cm2 at 0.58 ViR-free under H2/air (1.5/1.8 stoic.), 80 oC, 40% RH, 150 kPaabs. outlet pressure.

Catalyst MAInitial (A mgPt

-1)

MA30k (A mgPt

-1)

ECSAInitial (%)

ECSA30k (%)

Pt2Ni/CNC (L) Pt2Ni/CNC (NL)

0.44

0.44

0.28 (36% loss)

0.30 (31.8% loss)

24.6

24.3

16.9 (31% loss)

17.9 (26.3% loss)

18

0.1 1

0.82

0.84

0.86

0.88

0.90

0.92

0.94

iR-c

orre

cted

cel

l vol

tage

(V)

Mass activity (A mgPt-1)

Pt2Ni/CNC (L) (0.44 A mgPt-1)

Pt2Ni/CNC (NL) (0.44 A mgPt-1)

Pt2Ni/CNC (New) (0.44 A mgPt-1)

H2/O2 (2/9.5 stoic.)80 oC, 100% RH150 kPaabs. back press.

Technical Accomplishments Progress in Catalyst Stability Studies of Pt-alloy/CNC Catalysts (YU) (0.6-1.0 V Cycling)

HIGHLIGHT: (Milestone 2) • YU catalysts show mass activities of 0.44 for Pt2Ni/CNC (L), Pt2Ni/CNC (NL) and Pt2Ni/CNC(New) catalysts. New = CNC under development at YU

NL – Not Leached L - Leached

Catalyst Durability Test (Potential Cycling between 0.6 and1.0 V)

HIGHLIGHT: (Status against 2017 DOE targets) • Pt2Ni/CNC (L) catalyst shows mass activity loss of 36%

and ECSA loss of 31% after 30 k cycles. This catalyst satisfies the 2017 DOE target of ≤40% loss of mass activity and ECSA after 30 k cycles. (Milestone 3)

• Pt2Ni/CNC (NL) catalyst shows mass activity loss of 31.8% and ECSA loss of 26.3% after 30 k cycles. This catalyst satisfies the 2017 DOE target of ≤40% loss of mass activity and ECSA after 30 k cycles. (Milestone 3)

DOE Accelerated Protocol

0.6 ~ 1.0 V, 50mV/s, 30,000 cycle, H2/N2

80oC, 100 % RH, single cell 25cm2

Catalysts : Yonsei U. Pt-alloy/CNC, 0.1mgmetal/cm2

Pt mass activity : H2/O2, 2.0/9.5 stoic, 100% RH, 80oC, 150 kPa

19

Technical Accomplishments Progress in Support Durability Studies of Pt-alloy/CNC Catalysts (YU) (1.2 V Potential Holding)

Catalyst MAInitial (A mgPt

-1)

MA400h (A mgPt

-1)

ECSAInitial m2/gPt

ECSA400h m2/gPt

Pt2Ni/CNC (L) Pt2Ni/CNC (NL)

0.44 0.44

0.2 (54% loss) 0.23 (47.7% loss)

24.6 24.3

12.5 (49% loss) 14.0 (42.4% loss)

HIGHLIGHT: (Status against 2017 DOE targets) • YU catalysts show mass activities of 0.44 and 0.44 for Pt2Ni/CNC (L) and Pt2Ni/CNC (NL) catalysts,

respectively. • Pt2Ni/CNC (L) catalyst shows mass activity loss of 54% and ECSA loss of 12.5% after 400 h. • Pt2Ni/CNC (NL) catalyst shows mass activity loss of 47.7% and ECSA loss of 14.0% after 400 h. • The 2017 DOE target is ≤40% loss of mass activity and ECSA after 400 h potential holding at 1.2 V.

(Milestone 3)

DOE Accelerated Protocol

Hold at 1.2V for 24 h, H2/N2

80oC, 150 kPa, 100 % RH, single cell 25cm2

Catalyst : Yonsei U. Pt2Ni1/C, 0.1mgmetal/cm2

Pt mass activity : H2/O2, 2.0/9.5 stoic, 100% RH,

80oC, 150 kPa

NL – Not Leached; L - Leached

Support Stability Test (Potential Holding at 1.2 V)

CNC Pt2Ni/CNC(L)

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Collaborations

Subcontractors: Yonsei University

Activation procedure to deposit Pt on graphitic carbon support. Pt-alloy/CNC catalyst development with high mass activity, specific activity and

durability. Process to control the particle size at high temperature treatment. Evaluation of high current density performance under H2-air. Support corrosion mechanism studies.

Hyundai Motor Company (Funding ended Dec. 2011 and will resume in Phase II) Pt-Pd catalyst development and performance evaluation. Flow-field design optimization. Short-stack design and construction. Performance evaluation of Pt/C catalyst under short-stack conditions. Construction and delivery of short-stack (10 cells, 50 cm2) to University of South

Carolina. HMC delivered a short-stack (50 cm2) in Nov 2011. Additional Interactions:

Rudiger Laufhutte (University of Illinois, Urbana Champagne): ICP analysis of Pt-alloy catalysts. JoAn Hudson & Haijun Qian (Clemson University): Transmission Electron Microscopy analysis. Soumitra Goshroy (EM Center, USC): HR-TEM analysis Scribner Associates: Design and construction of fuel cell test station according to USC

requirements. Fuel Cell Technologies: Design and construction of 25 and 50 cm2 single cells according to USC

specifications.

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Future Work

In the future work during the no-cost extension period (April 01, 2013 – September 30, 2013), we plan to continue with the progress made so far with the HCC catalysts and further research will be focused on the following tasks:

Task 1: Transition metal content optimization studies and synthesis of Pt-alloy/CCC250 catalysts containing low transition metal content (<8 wt.%) in the alloy using the procedure developed at USC.

Task 2: Transition metal content optimization studies and synthesis of Pt-alloy/CNC catalysts containing low transition metal content (<8 wt.%) in the alloy.

Task 3: Synthesis of highly stable graphitized CCC and CNC supports. These supports will be synthesized by using two different methods which require (i) preparation of carbon composite support synthesized at 900 oC and (ii) removal of amorphous carbon from the CCC and CNC support by chemical oxidation at elevated temperature in the presence of oxygen. The CCC and CNC supports will also be synthesized using transition metal containing precursors at elevated temperatures (between 700 and 1500 oC). The goal is to obtain CCC and CNC supports with BET surface area of 150 m2/g only by heating and/or removal of any amorphous carbon present by means of chemical oxidation. Our preliminary studies indicated that the percentage of amorphous carbon decreases due to the high temperature annealing procedure.

Subtask 3.1: Optimizing the procedures to purify the high temperature treated carbon composite supports to remove transition metals and amorphous carbon.

Task 4: Deposition of Pt-alloy catalysts on 140-180 m2/g highly graphitized carbon composite supports which are completely purified to remove both amorphous carbon and traces of transition metals.

The goal is to select a best performing catalysts which satisfy the 2017 DOE requirements of ≤40% loss of mass activity, ≤40% loss of ECSA and <30 mV loss at 0.8 A/cm2 under H2-air after 30 k potential cycling (between 0.6 and 1.0 V) and potential holding (at 1.2 V for 400 h) experiments.

Characteristic Units 2017 Targets Status

PGM total loading mgPt/cm2 0.125 0.15-0.2 mgcatalyst/cm2 with USC Pt/CCC250, HCC250, Pt2Ni1/CCC<600, Pt1Co1/CCC380 and 0.19 mgcatalyst/cm2

with YU Pt2Ni1/CNC

PGM total content gPt/kW (rated) 0.18 0.39 (33% Pt1Co1/CCC380) – USC 0.36 (35% Pt/CCC250 and HCC250) – USC 0.34 (46% Pt2Ni/CCC<600) - USC 0.37 (50% Pt2Ni/CNC-NL) – YU

Mass activity (80 oC, 100% RH, 150 kPaabs.)

A/mgPt @ 0.9 ViR-free 0.44 0.43 (USC Pt2Ni1/CCC<600 ) 0.38 (USC HCC250) 0.37 (USC HCCC380) 0.44 (YU Pt2Ni1/CNC) (Milestone 2)

Catalyst durability (30,000 cycles 0.6-1.0 V, 50 mV/s, 80/80/80, 100 kPaabs., H2/N2)

% Mass activity loss % ECSA loss

mV loss @ 0.8 A/cm2

≤40% ≤40%

≤ 30 mV

47% (mass activity) & 15% (ECSA) for USC HCC250 53 mV loss at 0.8A/cm2 under H2-air for USC HCC250 46% (mass activity) & 19% (ECSA) for USC HCC380 53% (mass activity) & 27.8% (ECSA) for USC Pt2Ni1/CCC<600) 31.8% (mass activity) & 26.3% (ECSA) for YU Pt2Ni1/CNC (Milestone 3)

Support durability (1.2 V for 400 h at 80 oC, H2-N2, 150 kPaabs. 100% RH)

% Mass activity loss % ECSA loss

mV loss @ 0.8 A/cm2

≤40% ≤40%

≤ 30 mV

50% mass activity loss and 42% ECSA loss for USC HCC250 29 mV loss at 0.8 A/cm2 under H2-air for USC HCC250 47% mass activity loss and 64% ECSA loss for the USC Pt/CCC250 118 mV loss at 0.8 A/cm2 under H2-air for the USC Pt/CCC250 47.7% mass activity loss and 42.7% ECSA loss For YU Pt2Ni1/CNC (NL) (Milestone 3) 22

Summary: Status Against 2017 DOE Targets (As of March 2013)

23

Team Members who contributed to this presentation University of South Carolina Branko N. Popov, Tae-keun Kim, Won-suk Jung, Xie Tianyuan, Joseph Rotchford, Akos Kriston and Prabhu Ganesan Yonsei University (S. Korea) Hansung Kim

Hyun-suk Oh Woong Hee Lee

Acknowledgement

U.S. Department of Energy

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