Fabrication of electrodes with ultralow platinum loading by RF plasma processing of self-assembled arrays of Au@Pt nanoparticles

Conductive, carbon-free, electrocatalytically active, nanostructured electrodes with ultra-low platinum loading were fabricated using self-assembly of octadecanethiol-coated Au@Pt nanoparticles followed by RF plasma treatment. Bilayer arrays of Au@Pt nanoparticles with platinum loadings of 0.50, 1.04, 1.44, and 1.75 μg cm−2 (corresponding to 0.5, 1, 1.5 and 2 atomic layer coverage of platinum on nominally 5 nm gold core) were subjected to RF argon plasma treatment for various durations and their electrical conductivity, morphological evolution, and electrocatalytic activity characterized. Samples with monolayer and above platinum coverages exhibit maximum electrochemically active surface areas values of ∼100 m2/gpt and specific activities that are ∼4× to 6× of a reference platinum nanoparticle bilayer array. The underlying gold core influences the structural evolution of the samples upon RF plasma treatment and leads to the formation of highly active Pt(110) facets on the surface at an optimal plasma treatment duration, which also corresponds to the onset of a sharp decline in lateral sheet resistance. The sample having a two atom thick platinum coating has the highest total mass activity of 48 ± 3 m2/g(pt+au), corresponding to 44% Pt atom utilization, while also exhibiting enhanced CO tolerance as well as high methanol oxidation reaction and oxygen reduction reaction activity.

[1]  Ryan O'Hayre,et al.  A review on direct methanol fuel cells–In the perspective of energy and sustainability , 2015 .

[2]  Nobuhiko Nakagaki,et al.  The Newly Developed Components for the Fuel Cell Vehicle, Mirai , 2015 .

[3]  B. Hwang,et al.  Nanoporous gyroid platinum with high catalytic activity from block copolymer templates via electroless plating , 2015 .

[4]  V. Santhanam,et al.  Synthesis and Characterization of Au@Pt Nanoparticles with Ultrathin Platinum Overlayers , 2015 .

[5]  T. Hatanaka,et al.  Fabrication and Cell Analysis of a Pt/SiO2 Platinum Thin Film Electrode , 2014 .

[6]  R. Cao,et al.  Recent Advances in the Stabilization of Platinum Electrocatalysts for Fuel‐Cell Reactions , 2014 .

[7]  J. Solla-Gullón,et al.  Electrocatalysis on Shape-Controlled Pt Nanoparticles , 2013 .

[8]  Dusan Strmcnik,et al.  Mesostructured thin films as electrocatalysts with tunable composition and surface morphology. , 2012, Nature materials.

[9]  R. Zengerle,et al.  Porous Platinum Electrodes Fabricated by Cyclic Electrodeposition of PtCu Alloy: Application to Implantable Glucose Fuel Cells , 2012 .

[10]  V. Santhanam,et al.  Realization of thermally durable close-packed 2D gold nanoparticle arrays using self-assembly and plasma etching , 2012, Nanotechnology.

[11]  Mark K. Debe,et al.  Electrocatalyst approaches and challenges for automotive fuel cells , 2012, Nature.

[12]  Seeram Ramakrishna,et al.  Progress and perspectives in micro direct methanol fuel cell , 2012 .

[13]  R. Zengerle,et al.  Strategies for the Fabrication of Porous Platinum Electrodes , 2011, Advanced materials.

[14]  M. Fayette,et al.  All electrochemical fabrication of a platinized nanoporous Au thin-film catalyst. , 2011, ACS applied materials & interfaces.

[15]  Q. Xie,et al.  Au/Pt and Au/Pt3Ni nanowires as self-supported electrocatalysts with high activity and durability for oxygen reduction. , 2011, Chemical communications.

[16]  T. Baumann,et al.  ALD functionalized nanoporous gold: thermal stability, mechanical properties, and catalytic activity. , 2011, Nano letters.

[17]  E. Antolini,et al.  The renaissance of unsupported nanostructured catalysts for low-temperature fuel cells: from the size to the shape of metal nanostructures , 2011, Journal of Materials Science.

[18]  Dingsheng Wang,et al.  Bimetallic Nanocrystals: Liquid‐Phase Synthesis and Catalytic Applications , 2011, Advanced materials.

[19]  M. Debe.  Novel catalysts, catalysts support and catalysts coated membrane methods , 2010 .

[20]  V. Santhanam,et al.  Room-temperature synthesis of gold nanoparticles — Size-control by slow addition , 2010 .

[21]  S. Alia,et al.  Porous Platinum Nanotubes for Oxygen Reduction and Methanol Oxidation Reactions , 2010 .

[22]  Jin Luo,et al.  Nanoscale Alloying, Phase-Segregation, and Core−Shell Evolution of Gold−Platinum Nanoparticles and Their Electrocatalytic Effect on Oxygen Reduction Reaction , 2010 .

[23]  Michael F Toney,et al.  Lattice-strain control of the activity in dealloyed core-shell fuel cell catalysts. , 2010, Nature chemistry.

[24]  Zhenmeng Peng,et al.  PtAu bimetallic heteronanostructures made by post-synthesis modification of Pt-on-Au nanoparticles , 2009 .

[25]  Xingbo Ge,et al.  Tailoring the Structure and Property of Pt-Decorated Nanoporous Gold by Thermal Annealing , 2009 .

[26]  Hong Yang,et al.  Designer platinum nanoparticles: Control of shape, composition in alloy, nanostructure and electrocatalytic property , 2009 .

[27]  Houyi Ma,et al.  Facile fabrication of ultrathin Pt overlayers onto nanoporous metal membranes via repeated Cu UPD and in situ redox replacement reaction. , 2009, Langmuir : the ACS journal of surfaces and colloids.

[28]  S. Hoeppener,et al.  The electrooxidation of small organic molecules on platinum nanoparticles supported on gold: influence of platinum deposition procedure , 2008 .

[29]  Sungho V. Park,et al.  Three-dimensional Pt-coated Au nanoparticle arrays: applications for electrocatalysis and surface-enhanced Raman scattering. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[30]  Peter N. Njoki,et al.  Synergistic activity of gold-platinum alloy nanoparticle catalysts , 2007 .

[31]  J. Erlebacher,et al.  Platinum-plated nanoporous gold : An efficient, low Pt loading electrocatalyst for PEM fuel cells , 2007 .

[32]  Bo-Qing Xu,et al.  Platinum covering of gold nanoparticles for utilization enhancement of Pt in electrocatalysts. , 2006, Physical chemistry chemical physics : PCCP.

[33]  Mark K. Debe,et al.  High voltage stability of nanostructured thin film catalysts for PEM fuel cells , 2006 .

[34]  Jin Luo,et al.  Activity-composition correlation of AuPt alloy nanoparticle catalysts in electrocatalytic reduction of oxygen , 2006 .

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

[36]  H. Gasteiger,et al.  Activity benchmarks and requirements for Pt, Pt-alloy, and non-Pt oxygen reduction catalysts for PEMFCs , 2005 .

[37]  Š. Pick,et al.  Angle resolved X-ray photoelectron spectroscopy study of Au deposited on Pt and Re surfaces , 2004 .

[38]  Petrus Christiaan Pistorius,et al.  The electrochemistry of gold–platinum alloys , 2004 .

[39]  B. Sures,et al.  Platinum‐Group Metals , 2004 .

[40]  P. Ross,et al.  Surface science studies of model fuel cell electrocatalysts , 2002 .

[41]  S. Srinivasan,et al.  Quantum jumps in the PEMFC science and technology from the 1960s to the year 2000 Part I. Fundamental scientific aspects , 2001 .

[42]  Paola Costamagna,et al.  Quantum jumps in the PEMFC science and technology from the 1960s to the year 2000 ☆: Part II. Engineering, technology development and application aspects , 2001 .

[43]  J. Nørskov,et al.  How a gold substrate can increase the reactivity of a Pt overlayer , 1999 .

[44]  K. Kinoshita,et al.  Particle Size Effects for Oxygen Reduction on Highly Dispersed Platinum in Acid Electrolytes , 1990 .

[45]  E. Yeung,et al.  Self-assembly of Au–Pt core–shell nanoparticles for effective enhancement of methanol electrooxidation , 2013 .

[46]  H. Gasteiger,et al.  PEM Fuel Cells, Materials and Design Development Challenges , 2013 .

[47]  Mark K. Debe,et al.  Tutorial on the Fundamental Characteristics and Practical Properties of Nanostructured Thin Film (NSTF) Catalysts , 2013 .

[48]  Bongjin Simon Mun,et al.  Trends in electrocatalysis on extended and nanoscale Pt-bimetallic alloy surfaces. , 2007, Nature materials.