Activity–Stability Relationship in Au@Pt Nanoparticles for Electrocatalysis

Abstract

Despite breakthroughs in the activity of electrocatalysts for the oxygen reduction reaction (ORR), the development of nanoscale ORR electrocatalysts is still hindered by their instability. Here, to bridge the functional link between activity and stability, wellcontrolled Au@Pt (core@shell) nanoparticles are investigated. In situ monitoring of atomic dissolution and physicochemical analysis in conjunction with theoretical calculations reveal that the atomic-level stability of Au@Pt nanoparticle is attributed to the low surface coverage of OH and oxide on Pt, balancing between strain and ligand effect of Au at the interface. Considering the relationships in activity− stability−oxophilicity, the functional links between activity and stability in the ORR are discussed, and the regulation of oxophilicity is suggested as a guideline for designing highly active and durable electrocatalysts for fuel cell applications.

Resolving the nanoparticles' structure-property relationships at the atomic level: a study of Pt-based electrocatalysts

“…Thus one can conclude that in order to stabilize Pt-alloys, the focus should be more on stabilizing Pt itself than on the less-noble metal (e.g. addition of Au ( Chung et al., 2020 ; Gatalo et al., 2016 ; Kodama et al., 2016 ; Lopes et al., 2016 , 2020 )). We note that when Pt does not protect M the dissolution of M can also be observed (for example peak A2′).…”

Understanding the Crucial Significance of the Temperature and Potential Window on the Stability of Carbon Supported Pt-Alloy Nanoparticles as Oxygen Reduction Reaction Electrocatalysts

“… 39 − 41 In addition to these studies, Cherevko and co-workers 42 followed with the first study on the temperature-dependent dissolution of polycrystalline Pt by coupling of the scanning flow cell (SFC) with an inductively coupled plasma mass spectrometer (ICP-MS). SFC-ICP-MS along with other recently used similar methodologies 26 , 30 , 43 − 48 enables insights into the time-and-potential resolved dissolution of metals, providing yet another dimension to the observed electrochemical signal. Specifically to the above-mentioned work by Cherevko and co-workers, 42 the authors reported a rather significant influence of temperature on the onsets of both the Pt-oxide formation as well as the reduction.…”

Highly Porous Au–Pt Bimetallic Urchin-Like Nanocrystals for Efficient Electrochemical Methanol Oxidation

“…In particular, Pt-based NCs have been extensively investigated as a potential candidate material for various electrochemical reactions including electrochemical fuel oxidation, oxygen reduction, sensing, and hydrogen evolution by water splitting [10][11][12][13][14]. Meanwhile, given Au is catalytically more inert than other metals, bimetallic materials prepared by integrating Au into active metals exhibit excellent catalytic performances in various electrochemical reactions [15,16]. In this context, recently developed Au-Pt bimetallic NCs show distinct catalytic effects compared with single Pt and Au NCs, which has aroused fundamental interest for enhanced functionalities and catalysis applications [17][18][19].…”

“…In this context, recently developed Au-Pt bimetallic NCs show distinct catalytic effects compared with single Pt and Au NCs, which has aroused fundamental interest for enhanced functionalities and catalysis applications [17][18][19]. In particular, Au-Pt bimetallic NCs exhibit enhanced electrocatalytic performance in fuel oxidation reactions in polymer electrolyte membrane fuel cells (PEMFC) because surface Au atoms can suppress the formation of carbonaceous molecules, which can be strongly adsorbed on the surface of NCs [16,[20][21][22]. To fully exploit the advantages of bimetallic NCs for electrocatalysis, highly porous structures are promising candidates due to their high-surface area-to-volume ratios [23][24][25][26][27].…”