Huge Instability of Pt/C Catalysts in Alkaline Medium

The stability of carbon-supported electrocatalysts has been largely investigated in acidic electrolytes, but the literature is much scarcer regarding similar stability studies in alkaline medium. Herein, the degradation of Vulcan XC-72-supported platinum nanoparticles (noted Pt/C), a state-of-the-art proton exchange membrane fuel cell electrocatalyst, is investigated in alkaline medium by combining electrochemical measurements and identical location transmission electron microscopy; electrochemical surface area (ECSA) losses were bridged to electrocatalyst morphological changes. The results demonstrate that the degradation in 0.1 M NaOH at 25 °C is severe (60% of ECSA loss after only 150 cycles between 0.1 and 1.23 V vs RHE), which is about 3 times worse than in acidic media for this soft accelerated stress test. Severe carbon corrosion has been ruled out according to Raman spectroscopy and X-ray photoelectron spectroscopy measurements, and it seems that the chemistry of the carbon support (in particular,...

[1]  E. Ticianelli,et al.  Accelerated degradation of Pt3Co/C and Pt/C electrocatalysts studied by identical-location transmission electron microscopy in polymer electrolyte environment , 2015 .

[2]  M. Chatenet,et al.  Borohydride Electrooxidation on Carbon-Supported Noble Metal Nanoparticles: Insights into Hydrogen and Hydroxyborane Formation , 2015 .

[3]  A. Ohma,et al.  Influence of Electrolyte Composition and pH on Platinum Electrochemical and/or Chemical Dissolution in Aqueous Acidic Media , 2015 .

[4]  Laetitia Dubau,et al.  Carbon corrosion induced by membrane failure: The weak link of \PEMFC\ long-term performance , 2014 .

[5]  M. Mermoux,et al.  Carbon Corrosion in Proton-Exchange Membrane Fuel Cells: From Model Experiments to Real-Life Operation in Membrane Electrode Assemblies , 2014 .

[6]  Gareth P. Keeley,et al.  A comparative study on gold and platinum dissolution in acidic and alkaline media , 2014 .

[7]  F. Maillard,et al.  An identical-location transmission electron microscopy study on the degradation of Pt/C nanoparticles under oxidizing, reducing and neutral atmosphere , 2013 .

[8]  Laetitia Dubau,et al.  Degradation heterogeneities induced by repetitive start/stop events in proton exchange membrane fuel cell: Inlet vs. outlet and channel vs. land , 2013 .

[9]  E. Ticianelli,et al.  Identical-Location Transmission Electron Microscopy Study of Pt/C and Pt–Co/C Nanostructured Electrocatalyst Aging: Effects of Morphological and Compositional Changes on the Oxygen Reduction Reaction Activity , 2013, Electrocatalysis.

[10]  E. Ticianelli,et al.  In situ Fourier transform infrared spectroscopy and on-line differential electrochemical mass spectrometry study of the NH3BH3 oxidation reaction on gold electrodes , 2013 .

[11]  F. Maillard,et al.  Evidences of the migration of Pt crystallites on high surface area carbon supports in the presence of reducing molecules , 2012 .

[12]  A. Kostka,et al.  Stability investigations of electrocatalysts on the nanoscale , 2012 .

[13]  Laetitia Dubau,et al.  Durability of Pt3Co / C Cathodes in a 16 Cell PEMFC Stack: Macro/Microstructural Changes and Degradation Mechanisms , 2010 .

[14]  S. Kocha,et al.  Examination of the activity and durability of PEMFC catalysts in liquid electrolytes , 2010 .

[15]  Edward F. Holby,et al.  Instability of Supported Platinum Nanoparticles in Low-Temperature Fuel Cells , 2007 .

[16]  Frédéric Maillard,et al.  Membrane and Active Layer Degradation upon PEMFC Steady-State Operation I. Platinum Dissolution and Redistribution within the MEA , 2007 .

[17]  F. Maillard,et al.  Detection of Pt z + Ions and Pt Nanoparticles Inside the Membrane of a Used PEMFC , 2007 .

[18]  U. Stimming,et al.  Influence of particle agglomeration on the catalytic activity of carbon-supported Pt nanoparticles in CO monolayer oxidation , 2005 .

[19]  Hubert A. Gasteiger,et al.  Instability of Pt ∕ C Electrocatalysts in Proton Exchange Membrane Fuel Cells A Mechanistic Investigation , 2005 .

[20]  M. Eikerling,et al.  Size effects on reactivity of Pt nanoparticles in CO monolayer oxidation: the role of surface mobility. , 2004, Faraday discussions.

[21]  U. Stimming,et al.  Infrared spectroscopic study of CO adsorption and electro-oxidation on carbon-supported Pt nanoparticles: Interparticle versus intraparticle heterogeneity , 2004 .