PtCo Cathode Catalyst Morphological and Compositional Changes after PEM Fuel Cell Accelerated Stress Testing

Sneed, Brian T.; Cullen, David A.; Mukundan, R.; Borup, Rodney L.; More, Karren L.

doi:10.1149/2.0091806jes

Title: PtCo Cathode Catalyst Morphological and Compositional Changes after PEM Fuel Cell Accelerated Stress Testing

Abstract

Development of Pt catalysts alloyed with transition metals has led to a new class of state-of-the-art electrocatalysts for oxygen reduction at the cathode of proton exchange membrane fuel cells; however, the durability of Pt-based alloy catalysts is challenged by poor structural and chemical stability. There is a need for better understanding of the morphological and compositional changes that occur to the catalyst under fuel cell operation. Here, we report in-depth characterization results of a Pt-Co electrocatalyst incorporated in the cathode of membrane electrode assemblies, which were evaluated before and after accelerated stress tests designed specifically to enhance catalyst degradation. Electron microscopy, spectroscopy, and 3D electron tomography analyses of the Pt-Co nanoparticle structures suggest that the small- and intermediate-sized Pt-Co particles, which are typically Pt-rich in the fresh condition, undergo minimal morphological changes, whereas intermediate- and larger-sized Pt-Co nanoparticles that exhibit a porous “spongy” morphology and initially have a higher Co content, transform into hollowed-out shells, which is driven by continuous leaching of Co from the Pt-Co catalysts. We further show how these primary Pt-Co nanoparticle morphologies group toward a lower Co, larger size portion of the size vs. composition distribution, and provide details of their nanoscale morphological features.

Authors:

Sneed, Brian T. ^[1]; Cullen, David A. ^[2];

^[3];

^[1]

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Publication Date:: 2018-03-01

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Energy Efficiency and Renewable Energy (EERE). Fuel Cell Technologies Program (EE-3F); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities Division; USDOE Office of Nuclear Energy (NE), Fuel Cycle Technologies (NE-5)

OSTI Identifier:: 1441340

Alternate Identifier(s):: OSTI ID: 1460172

Report Number(s):: LA-UR-18-20370
Journal ID: ISSN 0013-4651

Grant/Contract Number:: AC52-06NA25396; AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: Journal of the Electrochemical Society

Additional Journal Information:: Journal Volume: 165; Journal Issue: 6; Journal ID: ISSN 0013-4651

Publisher:: The Electrochemical Society

Country of Publication:: United States

Language:: English

Subject:: 30 DIRECT ENERGY CONVERSION; Energy Sciences; Fuel Cell, Durability, PtCo, catalysis

Citation Formats


                    Sneed, Brian T., Cullen, David A., Mukundan, R., Borup, Rodney L., and More, Karren L.. PtCo Cathode Catalyst Morphological and Compositional Changes after PEM Fuel Cell Accelerated Stress Testing.  United States: N. p., 2018. 
Web.  doi:10.1149/2.0091806jes.

Copy to clipboard


                    Sneed, Brian T., Cullen, David A., Mukundan, R., Borup, Rodney L., & More, Karren L.. PtCo Cathode Catalyst Morphological and Compositional Changes after PEM Fuel Cell Accelerated Stress Testing.  United States.  https://doi.org/10.1149/2.0091806jes

Copy to clipboard


                    Sneed, Brian T., Cullen, David A., Mukundan, R., Borup, Rodney L., and More, Karren L.. Thu .  
"PtCo Cathode Catalyst Morphological and Compositional Changes after PEM Fuel Cell Accelerated Stress Testing".  United States.  https://doi.org/10.1149/2.0091806jes.  https://www.osti.gov/servlets/purl/1441340.

Copy to clipboard


                    
@article{osti_1441340,

  title        = {PtCo Cathode Catalyst Morphological and Compositional Changes after PEM Fuel Cell Accelerated Stress Testing},

  author       = {Sneed, Brian T. and Cullen, David A. and Mukundan, R. and Borup, Rodney L. and More, Karren L.},

  abstractNote = {Development of Pt catalysts alloyed with transition metals has led to a new class of state-of-the-art electrocatalysts for oxygen reduction at the cathode of proton exchange membrane fuel cells; however, the durability of Pt-based alloy catalysts is challenged by poor structural and chemical stability. There is a need for better understanding of the morphological and compositional changes that occur to the catalyst under fuel cell operation. Here, we report in-depth characterization results of a Pt-Co electrocatalyst incorporated in the cathode of membrane electrode assemblies, which were evaluated before and after accelerated stress tests designed specifically to enhance catalyst degradation. Electron microscopy, spectroscopy, and 3D electron tomography analyses of the Pt-Co nanoparticle structures suggest that the small- and intermediate-sized Pt-Co particles, which are typically Pt-rich in the fresh condition, undergo minimal morphological changes, whereas intermediate- and larger-sized Pt-Co nanoparticles that exhibit a porous “spongy” morphology and initially have a higher Co content, transform into hollowed-out shells, which is driven by continuous leaching of Co from the Pt-Co catalysts. We further show how these primary Pt-Co nanoparticle morphologies group toward a lower Co, larger size portion of the size vs. composition distribution, and provide details of their nanoscale morphological features.},

  doi          = {10.1149/2.0091806jes},

  journal      = {Journal of the Electrochemical Society},

  number       = 6,

  volume       = 165,

  place        = {United States},

  year         = {2018},

  month        = {3}

}

Copy to clipboard

Journal Article:

Free Publicly Available Full Text

Accepted Manuscript (DOE)

Publisher's Version of Record

https://doi.org/10.1149/2.0091806jes

Other availability

Search WorldCat to find libraries that may hold this journal

Citation Metrics:

Cited by: 20 works

Citation information provided by
Web of Science

Save / Share:

Export Metadata

Save to My Library

Works referenced in this record:

Structurally ordered intermetallic platinum–cobalt core–shell nanoparticles with enhanced activity and stability as oxygen reduction electrocatalysts
journal, October 2012

Wang, Deli; Xin, Huolin L.; Hovden, Robert
Nature Materials, Vol. 12, Issue 1, p. 81-87
DOI: 10.1038/nmat3458

Recent Advances in Electrocatalysts for Oxygen Reduction Reaction
journal, February 2016

Shao, Minhua; Chang, Qiaowan; Dodelet, Jean-Pol
Chemical Reviews, Vol. 116, Issue 6
DOI: 10.1021/acs.chemrev.5b00462

3D Analysis of Fuel Cell Electrocatalyst Degradation on Alternate Carbon Supports
journal, August 2017

Sneed, Brian T.; Cullen, David A.; Reeves, Kimberly S.
ACS Applied Materials & Interfaces, Vol. 9, Issue 35
DOI: 10.1021/acsami.7b09716

Understanding and Controlling Nanoporosity Formation for Improving the Stability of Bimetallic Fuel Cell Catalysts
journal, February 2013

Gan, Lin; Heggen, Marc; O’Malley, Rachel
Nano Letters, Vol. 13, Issue 3
DOI: 10.1021/nl304488q

The Priority and Challenge of High-Power Performance of Low-Platinum Proton-Exchange Membrane Fuel Cells
journal, March 2016

Kongkanand, Anusorn; Mathias, Mark F.
The Journal of Physical Chemistry Letters, Vol. 7, Issue 7
DOI: 10.1021/acs.jpclett.6b00216

Evolution of nanoporosity in dealloying
journal, March 2001

Erlebacher, Jonah; Aziz, Michael J.; Karma, Alain
Nature, Vol. 410, Issue 6827, p. 450-453
DOI: 10.1038/35068529

Experimental Methodologies to Understand Degradation of Nanostructured Electrocatalysts for PEM Fuel Cells: Advances and Opportunities
journal, June 2016

Mezzavilla, Stefano; Cherevko, Serhiy; Baldizzone, Claudio
ChemElectroChem, Vol. 3, Issue 10
DOI: 10.1002/celc.201600170

Spiny Rhombic Dodecahedral CuPt Nanoframes with Enhanced Catalytic Performance Synthesized from Cu Nanocube Templates
journal, June 2017

Lyu, Lian-Ming; Kao, Ya-Chuan; Cullen, David A.
Chemistry of Materials, Vol. 29, Issue 13
DOI: 10.1021/acs.chemmater.7b01550

Stability of Dealloyed Porous Pt/Ni Nanoparticles
journal, July 2015

Baldizzone, Claudio; Gan, Lin; Hodnik, Nejc
ACS Catalysis, Vol. 5, Issue 9
DOI: 10.1021/acscatal.5b01151

Control of Architecture in Rhombic Dodecahedral Pt–Ni Nanoframe Electrocatalysts
journal, August 2017

Becknell, Nigel; Son, Yoonkook; Kim, Dohyung
Journal of the American Chemical Society, Vol. 139, Issue 34
DOI: 10.1021/jacs.7b05584

Atomic-Resolution Spectroscopic Imaging of Ensembles of Nanocatalyst Particles Across the Life of a Fuel Cell
journal, December 2011

Xin, Huolin L.; Mundy, Julia A.; Liu, Zhongyi
Nano Letters, Vol. 12, Issue 1
DOI: 10.1021/nl203975u

Platinum-Alloy Cathode Catalyst Degradation in Proton Exchange Membrane Fuel Cells: Nanometer-Scale Compositional and Morphological Changes
journal, January 2010

Chen, Shuo; Gasteiger, Hubert A.; Hayakawa, Katsuichiro
Journal of The Electrochemical Society, Vol. 157, Issue 1
DOI: 10.1149/1.3258275

Cationic Contamination Effects on Polymer Electrolyte Membrane Fuel Cell Performance
journal, January 2011

Kienitz, Brian; Pivovar, Bryan; Zawodzinski, Tom
Journal of The Electrochemical Society, Vol. 158, Issue 9
DOI: 10.1149/1.3610986

Origin of Oxygen Reduction Reaction Activity on “Pt ₃ Co” Nanoparticles: Atomically Resolved Chemical Compositions and Structures
journal, December 2008

Chen, Shuo; Sheng, Wenchao; Yabuuchi, Naoaki
The Journal of Physical Chemistry C, Vol. 113, Issue 3
DOI: 10.1021/jp807143e

Revealing the Atomic Restructuring of Pt–Co Nanoparticles
journal, May 2014

Xin, Huolin L.; Alayoglu, Selim; Tao, Runzhe
Nano Letters, Vol. 14, Issue 6
DOI: 10.1021/nl500553a

Identical Location Transmission Electron Microscopy Imaging of Site-Selective Pt Nanocatalysts: Electrochemical Activation and Surface Disordering
journal, November 2015

Arán-Ais, Rosa M.; Yu, Yingchao; Hovden, Robert
Journal of the American Chemical Society, Vol. 137, Issue 47
DOI: 10.1021/jacs.5b09553

Reversibility of Pt-Skin and Pt-Skeleton Nanostructures in Acidic Media
journal, January 2014

Durst, Julien; Lopez-Haro, Miguel; Dubau, Laetitia
The Journal of Physical Chemistry Letters, Vol. 5, Issue 3
DOI: 10.1021/jz4025707

Carbon-Supported Pt-Based Alloy Electrocatalysts for the Oxygen Reduction Reaction in Polymer Electrolyte Membrane Fuel Cells: Particle Size, Shape, and Composition Manipulation and Their Impact to Activity
journal, April 2015

Wang, Yan-Jie; Zhao, Nana; Fang, Baizeng
Chemical Reviews, Vol. 115, Issue 9
DOI: 10.1021/cr500519c

Structure/Processing/Properties Relationships in Nanoporous Nanoparticles As Applied to Catalysis of the Cathodic Oxygen Reduction Reaction
journal, May 2012

Snyder, Joshua; McCue, Ian; Livi, Ken
Journal of the American Chemical Society, Vol. 134, Issue 20
DOI: 10.1021/ja3019498

Three-Dimensional Tracking and Visualization of Hundreds of Pt−Co Fuel Cell Nanocatalysts During Electrochemical Aging
journal, January 2012

Yu, Yingchao; Xin, Huolin L.; Hovden, Robert
Nano Letters, Vol. 12, Issue 9
DOI: 10.1021/nl203920s

Kinetics and Mechanism of Redox Processes of Pt/C and Pt ₃ Co/C Cathode Electrocatalysts in a Polymer Electrolyte Fuel Cell during an Accelerated Durability Test
journal, August 2016

Ishiguro, Nozomu; Kityakarn, Sutasinee; Sekizawa, Oki
The Journal of Physical Chemistry C, Vol. 120, Issue 35
DOI: 10.1021/acs.jpcc.6b04437

Structure–Activity–Stability Relationships for Space-Confined Pt _x Ni _y Nanoparticles in the Oxygen Reduction Reaction
journal, November 2016

Mezzavilla, Stefano; Baldizzone, Claudio; Swertz, Ann-Christin
ACS Catalysis, Vol. 6, Issue 12
DOI: 10.1021/acscatal.6b02221

Thermodynamics and Kinetics of Platinum Dissolution from Carbon-Supported Electrocatalysts in Aqueous Media under Potentiostatic and Potentiodynamic Conditions
journal, January 2013

Ahluwalia, Rajesh K.; Arisetty, Srikanth; Wang, Xiaoping
Journal of The Electrochemical Society, Vol. 160, Issue 4
DOI: 10.1149/2.018306jes

Probing Degradation by IL-TEM: The Influence of Stress Test Conditions on the Degradation Mechanism
journal, January 2013

Zana, Alessandro; Speder, Jozsef; Roefzaad, Melanie
Journal of The Electrochemical Society, Vol. 160, Issue 6
DOI: 10.1149/2.078306jes

Record activity and stability of dealloyed bimetallic catalysts for proton exchange membrane fuel cells
journal, January 2015

Han, Binghong; Carlton, Christopher E.; Kongkanand, Anusorn
Energy & Environmental Science, Vol. 8, Issue 1
DOI: 10.1039/C4EE02144D

Correlative Energy-Dispersive X-Ray Spectroscopic Tomography and Atom Probe Tomography of the Phase Separation in an Alnico 8 Alloy
journal, December 2016

Guo, Wei; Sneed, Brian T.; Zhou, Lin
Microscopy and Microanalysis, Vol. 22, Issue 6
DOI: 10.1017/S1431927616012496

A Model Based Iterative Reconstruction Algorithm For High Angle Annular Dark Field-Scanning Transmission Electron Microscope (HAADF-STEM) Tomography
journal, November 2013

Venkatakrishnan, S. V.; Drummy, L. F.; Jackson, M. A.
IEEE Transactions on Image Processing, Vol. 22, Issue 11
DOI: 10.1109/TIP.2013.2277784

Model-Based Iterative Reconstruction for Bright-Field Electron Tomography
journal, March 2015

Venkatakrishnan, S. V.; Drummy, Lawrence F.; Jackson, Michael
IEEE Transactions on Computational Imaging, Vol. 1, Issue 1
DOI: 10.1109/TCI.2014.2371751

Evolution of Nanoporosity in Dealloying
text, January 2001

Erlebacher, Jonah; Aziz, Michael J.; Karma, Alain
arXiv
DOI: 10.48550/arxiv.cond-mat/0103615

Works referencing / citing this record:

Mitigation of PEM Fuel Cell Catalyst Degradation with Porous Carbon Supports
journal, January 2019

Padgett, Elliot; Yarlagadda, Venkata; Holtz, Megan E.
Journal of The Electrochemical Society, Vol. 166, Issue 4
DOI: 10.1149/2.0371904jes

Similar Records in DOE PAGES and OSTI.GOV collections:

High-Current Density Durability of Pt/C and PtCo/C Catalysts at Similar Particle Sizes in PEMFCs

Journal Article Ramaswamy, Nagappan ; Kumaraguru, Swami ; Gu, Wenbin ; ... - Journal of the Electrochemical Society

The durability of carbon supported PtCo-alloy based nanoparticle catalysts play a key role in the longevity of proton-exchange membrane fuel cells (PEMFC) in electric vehicle applications. To improve its durability, it is important to understand and mitigate the various factors that cause PtCo-based cathode catalyst layers (CCL) to lose performance over time. These factors include i) electrochemical surface area (ECSA) loss, ii) specific activity loss, iii) H⁺/O₂-transport changes and iv) Co²⁺contamination effects. We use a catalyst-specific accelerated stress test (AST) voltage cycling protocol to compare the durability of Pt and PtCo catalysts at similar average nanoparticle size and distribution. Ourmore »« less
https://doi.org/10.1149/1945-7111/abe5ea
High-Current Density Durability of Pt/C and PtCo/C Catalysts at Similar Particle Sizes in PEMFCs

Journal Article Ramaswamy, Nagappan ; Kumaraguru, Swami ; Gu, Wenbin ; ... - Journal of the Electrochemical Society

The durability of carbon supported PtCo-alloy based nanoparticle catalysts play a key role in the longevity of proton-exchange membrane fuel cells (PEMFC) in electric vehicle applications. To improve its durability, it is important to understand and mitigate the various factors that cause PtCo-based cathode catalyst layers (CCL) to lose performance over time. These factors include i) electrochemical surface area (ECSA) loss, ii) specific activity loss, iii) H ⁺ /O ₂ -transport changes and iv) Co ²⁺ contamination effects. We use a catalyst-specific accelerated stress test (AST) voltage cycling protocol to compare the durability of Pt and PtCo catalysts at similarmore »« less
https://doi.org/10.1149/1945-7111/abe5ea
PRELIMINARY IN-SITU X-RAY ABSORPTION FINE STRUCTURE EXAMINATION OF PT/C AND PTCO/C CATHODE CATALYSTS IN AN OPERATIONAL POLYMER ELECTROLYTE FUEL CELL

Journal Article Phelan, B T ; Myers, D J ; Smith, M C - Journal of Undergraduate Research

State-of-the-art polymer electrolyte fuel cells require a conditioning period to reach optimized cell performance. There is insuffi cient understanding about the behavior of catalysts during this period, especially with regard to the changing environment of the cathode electrocatalyst, which is typically Pt nanoparticles supported on high surface area Vulcan XC-72 carbon (Pt/C). The purpose of this research was to record preliminary observations of the changing environment during the conditioning phase using X-Ray Absorption Fine Structure (XAFS) spectroscopy. XAFS was recorded for a Pt/C cathode at the Pt L3-edge and a PtCo/C cathode at both the Pt L3-edge and Co K-edge.more »« less
Full Text Available
Dealloyed Pt-Cu Core-Shell Nanoparticle Electrocatalysts for Use in PEM Fuel Cell Cathodes

Journal Article Mani, P ; Srivastava, R ; Strasser, P - J. Phys. Chem. C112:2770,2008

We report the synthesis, characterization, and single fuel cell testing of a novel class of nanostructured Pt-Cu alloy particle materials for use as oxygen reduction electrocatalyst in polymer electrolyte membrane fuel cells. The active phase of the Pt alloy nanoparticle catalysts is prepared by electrochemical dissolution (voltammetric dealloying) of Cu surface atoms from Cu-rich Pt-Cu alloy precursors. Bulk and surface structural and compositional characterization suggests that the dealloyed active catalyst phase consists of a core-shell structure in which a multilayer Pt rich shell is surrounding a Pt-poor alloy particle core. The electrocatalytic Pt mass activity of the dealloyed core-shell particlesmore »« less
Final Project Report: Development of Micro-Structural Mitigation Strategies for PEM Fuel Cells: Morphological Simulations and Experimental Approaches

Technical Report Wessel, Silvia ; Harvey, David

The durability of PEM fuel cells is a primary requirement for large scale commercialization of these power systems in transportation and stationary market applications that target operational lifetimes of 5,000 hours and 40,000 hours by 2015, respectively. Key degradation modes contributing to fuel cell lifetime limitations have been largely associated with the platinum-based cathode catalyst layer. Furthermore, as fuel cells are driven to low cost materials and lower catalyst loadings in order to meet the cost targets for commercialization, the catalyst durability has become even more important. While over the past few years significant progress has been made in identifyingmore »« less
https://doi.org/10.2172/1087665

Full Text Available

Similar Records

Title: PtCo Cathode Catalyst Morphological and Compositional Changes after PEM Fuel Cell Accelerated Stress Testing

Abstract

Citation Formats

Structurally ordered intermetallic platinum–cobalt core–shell nanoparticles with enhanced activity and stability as oxygen reduction electrocatalysts journal, October 2012

Recent Advances in Electrocatalysts for Oxygen Reduction Reaction journal, February 2016

3D Analysis of Fuel Cell Electrocatalyst Degradation on Alternate Carbon Supports journal, August 2017

Understanding and Controlling Nanoporosity Formation for Improving the Stability of Bimetallic Fuel Cell Catalysts journal, February 2013

The Priority and Challenge of High-Power Performance of Low-Platinum Proton-Exchange Membrane Fuel Cells journal, March 2016

Evolution of nanoporosity in dealloying journal, March 2001

Experimental Methodologies to Understand Degradation of Nanostructured Electrocatalysts for PEM Fuel Cells: Advances and Opportunities journal, June 2016

Spiny Rhombic Dodecahedral CuPt Nanoframes with Enhanced Catalytic Performance Synthesized from Cu Nanocube Templates journal, June 2017

Stability of Dealloyed Porous Pt/Ni Nanoparticles journal, July 2015

Control of Architecture in Rhombic Dodecahedral Pt–Ni Nanoframe Electrocatalysts journal, August 2017

Atomic-Resolution Spectroscopic Imaging of Ensembles of Nanocatalyst Particles Across the Life of a Fuel Cell journal, December 2011

Platinum-Alloy Cathode Catalyst Degradation in Proton Exchange Membrane Fuel Cells: Nanometer-Scale Compositional and Morphological Changes journal, January 2010

Cationic Contamination Effects on Polymer Electrolyte Membrane Fuel Cell Performance journal, January 2011

Origin of Oxygen Reduction Reaction Activity on “Pt 3 Co” Nanoparticles: Atomically Resolved Chemical Compositions and Structures journal, December 2008

Revealing the Atomic Restructuring of Pt–Co Nanoparticles journal, May 2014

Identical Location Transmission Electron Microscopy Imaging of Site-Selective Pt Nanocatalysts: Electrochemical Activation and Surface Disordering journal, November 2015

Reversibility of Pt-Skin and Pt-Skeleton Nanostructures in Acidic Media journal, January 2014

Carbon-Supported Pt-Based Alloy Electrocatalysts for the Oxygen Reduction Reaction in Polymer Electrolyte Membrane Fuel Cells: Particle Size, Shape, and Composition Manipulation and Their Impact to Activity journal, April 2015

Structure/Processing/Properties Relationships in Nanoporous Nanoparticles As Applied to Catalysis of the Cathodic Oxygen Reduction Reaction journal, May 2012

Three-Dimensional Tracking and Visualization of Hundreds of Pt−Co Fuel Cell Nanocatalysts During Electrochemical Aging journal, January 2012

Kinetics and Mechanism of Redox Processes of Pt/C and Pt 3 Co/C Cathode Electrocatalysts in a Polymer Electrolyte Fuel Cell during an Accelerated Durability Test journal, August 2016

Structure–Activity–Stability Relationships for Space-Confined Pt x Ni y Nanoparticles in the Oxygen Reduction Reaction journal, November 2016

Thermodynamics and Kinetics of Platinum Dissolution from Carbon-Supported Electrocatalysts in Aqueous Media under Potentiostatic and Potentiodynamic Conditions journal, January 2013

Probing Degradation by IL-TEM: The Influence of Stress Test Conditions on the Degradation Mechanism journal, January 2013

Record activity and stability of dealloyed bimetallic catalysts for proton exchange membrane fuel cells journal, January 2015

Correlative Energy-Dispersive X-Ray Spectroscopic Tomography and Atom Probe Tomography of the Phase Separation in an Alnico 8 Alloy journal, December 2016

A Model Based Iterative Reconstruction Algorithm For High Angle Annular Dark Field-Scanning Transmission Electron Microscope (HAADF-STEM) Tomography journal, November 2013

Model-Based Iterative Reconstruction for Bright-Field Electron Tomography journal, March 2015

Evolution of Nanoporosity in Dealloying text, January 2001

Mitigation of PEM Fuel Cell Catalyst Degradation with Porous Carbon Supports journal, January 2019

Structurally ordered intermetallic platinum–cobalt core–shell nanoparticles with enhanced activity and stability as oxygen reduction electrocatalysts
journal, October 2012

Recent Advances in Electrocatalysts for Oxygen Reduction Reaction
journal, February 2016

3D Analysis of Fuel Cell Electrocatalyst Degradation on Alternate Carbon Supports
journal, August 2017

Understanding and Controlling Nanoporosity Formation for Improving the Stability of Bimetallic Fuel Cell Catalysts
journal, February 2013

The Priority and Challenge of High-Power Performance of Low-Platinum Proton-Exchange Membrane Fuel Cells
journal, March 2016

Evolution of nanoporosity in dealloying
journal, March 2001

Experimental Methodologies to Understand Degradation of Nanostructured Electrocatalysts for PEM Fuel Cells: Advances and Opportunities
journal, June 2016

Spiny Rhombic Dodecahedral CuPt Nanoframes with Enhanced Catalytic Performance Synthesized from Cu Nanocube Templates
journal, June 2017

Stability of Dealloyed Porous Pt/Ni Nanoparticles
journal, July 2015

Control of Architecture in Rhombic Dodecahedral Pt–Ni Nanoframe Electrocatalysts
journal, August 2017

Atomic-Resolution Spectroscopic Imaging of Ensembles of Nanocatalyst Particles Across the Life of a Fuel Cell
journal, December 2011

Platinum-Alloy Cathode Catalyst Degradation in Proton Exchange Membrane Fuel Cells: Nanometer-Scale Compositional and Morphological Changes
journal, January 2010

Cationic Contamination Effects on Polymer Electrolyte Membrane Fuel Cell Performance
journal, January 2011

Origin of Oxygen Reduction Reaction Activity on “Pt ₃ Co” Nanoparticles: Atomically Resolved Chemical Compositions and Structures
journal, December 2008

Revealing the Atomic Restructuring of Pt–Co Nanoparticles
journal, May 2014

Identical Location Transmission Electron Microscopy Imaging of Site-Selective Pt Nanocatalysts: Electrochemical Activation and Surface Disordering
journal, November 2015

Reversibility of Pt-Skin and Pt-Skeleton Nanostructures in Acidic Media
journal, January 2014

Carbon-Supported Pt-Based Alloy Electrocatalysts for the Oxygen Reduction Reaction in Polymer Electrolyte Membrane Fuel Cells: Particle Size, Shape, and Composition Manipulation and Their Impact to Activity
journal, April 2015

Structure/Processing/Properties Relationships in Nanoporous Nanoparticles As Applied to Catalysis of the Cathodic Oxygen Reduction Reaction
journal, May 2012

Three-Dimensional Tracking and Visualization of Hundreds of Pt−Co Fuel Cell Nanocatalysts During Electrochemical Aging
journal, January 2012

Kinetics and Mechanism of Redox Processes of Pt/C and Pt ₃ Co/C Cathode Electrocatalysts in a Polymer Electrolyte Fuel Cell during an Accelerated Durability Test
journal, August 2016

Structure–Activity–Stability Relationships for Space-Confined Pt _x Ni _y Nanoparticles in the Oxygen Reduction Reaction
journal, November 2016

Thermodynamics and Kinetics of Platinum Dissolution from Carbon-Supported Electrocatalysts in Aqueous Media under Potentiostatic and Potentiodynamic Conditions
journal, January 2013

Probing Degradation by IL-TEM: The Influence of Stress Test Conditions on the Degradation Mechanism
journal, January 2013

Record activity and stability of dealloyed bimetallic catalysts for proton exchange membrane fuel cells
journal, January 2015

Correlative Energy-Dispersive X-Ray Spectroscopic Tomography and Atom Probe Tomography of the Phase Separation in an Alnico 8 Alloy
journal, December 2016

A Model Based Iterative Reconstruction Algorithm For High Angle Annular Dark Field-Scanning Transmission Electron Microscope (HAADF-STEM) Tomography
journal, November 2013

Model-Based Iterative Reconstruction for Bright-Field Electron Tomography
journal, March 2015

Evolution of Nanoporosity in Dealloying
text, January 2001

Mitigation of PEM Fuel Cell Catalyst Degradation with Porous Carbon Supports
journal, January 2019