PGM-free OER Catalysts for Proton Exchange Membrane Electrolyzer

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1 PGM-free OER Catalysts for Proton Exchange Membrane Electrolyzer Di-Jia Liu, Argonne National Laboratory November 14, 2017 HydroGEN Kick-Off Meeting, National Renewable Energy Laboratory

2 HydroGEN Kick-Off Meeting PGM-free OER Catalysts for Proton Exchange Membrane Electrolyzer Lead: Di-Jia Liu, Argonne National Laboratory Sub: Gang Wu, U. of Buffalo, Hui Xu, Giner Inc. Award # Year 1 Funding EE $250,000 Project Vision To lower the capital cost of PEME by adopting precious-metal free OER electro-catalysts Project Impact MOF Current density / macm H 2 O 2H + + ½ O e E (V) / RHE To reduce the anode catalyst cost by 20 folds by developing one or more PGMfree OER catalysts with the performance approaching to that of Ir catalyst, demonstrated at PEME level. PNNE O 2 H + e - H 2 O HydroGEN: Advanced Water Splitting Materials 2

3 Innovation and Objectives Project history Both ANL and UB teams are the pioneers in the MOF derived PGM-free catalysts for oxygen redox reactions. The proposed concepts have been supported by preliminary data obtained at both institutes. Giner is a world leader in PEMWE technology development and commercialization. Barriers Activity: although PGM-free catalysts have been demonstrated respectable activity in alkaline media, few reported for acidic application. Durability: instability of most conductive supports under high polarization potential limits the lifetime of supported catalysts at present Proposed targets Metric State of the Art Proposed Difference in overpotentia ls against Ir black by RDE Current density in operating PEME Overpotential of PGM-free catalyst in acid ~530 10mA/cm 2 Non-existing for PGM-free catalyst in PEME Overpotential <350 mv or 15 mv higher than Ir 10mA/cm 2 in acidic electrolyte PEME/MEA with target performance of > 200 ma/cm 1.80 V Partnerships Computational chemistry and predictive modeling by LLNL and LBNL groups Advanced electron microscopic imaging by SNL group High throughput electrode and electrocatalyst synthesis support / characterization by NREL group. HydroGEN: Advanced Water Splitting Materials 3

4 Technology Innovation Metal-Organic Framework (MOF) Derived PGM-free OER Catalysts TM ion (SBU) Solvothermal High- Temperature + or Solid-state Reaction N-containing Organic Ligand Metal-Organic Framework (MOF) Pyrolysis & Treatment TM Composite Catalyst MOF derived TM composite catalysts can significantly reduce the cost and improve surface property / catalytic activity HydroGEN: Advanced Water Splitting Materials 4

5 Technology Innovation Porous Nano-Network Electrode (PNNE) via Electrospin at ANL Electrospinning Conversion to catalyst H + O 2 e - H 2 O Fabrication to electrode MOF embedded PNNE can improve OER mass-charge transfers and connectivity against oxidative corrosion HydroGEN: Advanced Water Splitting Materials 5

6 Technology Innovation Preliminary RDE ANL SEM/TEM Investigation Preliminary RDE investigation shows ANL s embedded PNNE catalyst with very promising activity and durability; validation at MEA level is needed HydroGEN: Advanced Water Splitting Materials 6

7 Technology Innovation UB s MOF-derived Fe x /N y /C z catalyst showing encouraging activity and stability for the OER in 0.5 M H 2 SO M H 2 SO 4, 900 rpm 50 Current Density (ma/mg) MOF-0.6 mg/cm 2 Current Density, ma/cm Ir loading: 60 g/cm 2 Ir Black_cycle 1 Ir Black_cycle 100 Ir Black_cycle 200 Ir Black_cycle 300 Ir Black_cycle Potential (V vs RHE) Ir-10 g/cm Potential (V vs. RHE) HydroGEN: Advanced Water Splitting Materials 7

8 Technology Innovation FeCoNiMn-derived carbon composites, which have shown remarkable stability in alkaline, will be studied in acids for PEM electrolyzers j / ma/cm Intial After 20k After 30k After 60k j 1.6V = (+) 79.5 NC-FeCoNiMn E 4 onset (mv) = (+) 50 E 1/2 (mv)= (+) E / V vs RHE Before cycling, (0-1.9 V) in 0.1 M NaOH 5 nm 5 nm After cycling 5 nm 5 nm HydroGEN: Advanced Water Splitting Materials 8

9 From RDE to MEA (Giner) Electrode design and development using a variety of aqueous and nonaqueous ionomer dispersions Catalyst ink processing and characterization (rheology, dynamic light scattering, zeta potential, and surface energy) Mitigated membranes to lower hydrogen crossover Dimension-stabilized membranes towards reduced membrane swelling and enhanced membrane mechanical stability Special anode gas diffusion media and bipolar plates for enhanced corrosion resistance HydroGEN: Advanced Water Splitting Materials 9

10 Electrolyzer Test Station and Hardware (Giner) Test Station Three cells can be tested simultaneously Up to 5000 ma/cm 2 for cm 2 hardware HFR embedded to measure cell resistance Remote control and H2 sensor Hardware HydroGEN: Advanced Water Splitting Materials 10

11 Effective Leveraging of the EMN Resource Nodes Computational Materials Diagnostics (LLNL) Predicative modeling to support better OER catalyst design; initial project discussion carried out in October Ab initio & DFT Calculation on OER Catalysis (LBNL) Improved understanding on active site structure & transition state during catalysis; Informal discussion carried out in August Advanced Electron Microscopy (SNL) High resolution imaging support to better understanding on catalyst morphology and composition; initial project discussion carried out in October Catalyst Characterization & High-throughput MEA/ Electrode Development (NREL) Surface and electrocatalytic characterization to support catalyst development; Informal discussion carried out in August Support MEA /electrode scale-up and testing; Informal discussion carried out in August HydroGEN: Advanced Water Splitting Materials 11

12 Acknowledgement Argonne National Laboratory Lina Chong Hao Wang University of Buffalo, SUNY Gang Wu Giner Inc. Hui Xu US DOE Office of Fuel Cell Technologies Eric Miller Program Manager Dave Peterson Project Manager HydroGEN: Advanced Water Splitting Materials 12

13 Thank You! HydroGEN: Advanced Water Splitting Materials 13