A Platinum Monolayer Core‐Shell Catalyst with a Ternary Alloy Nanoparticle Core and Enhanced Stability for the Oxygen Reduction Reaction

Abstract

We synthesize a platinum monolayer core-shell catalyst with a ternary alloy nanoparticle core of Pd, Ir, and Ni. A Pt monolayer is deposited on carbon-supported PdIrNi nanoparticles using an underpotential deposition method, in which a copper monolayer is applied to the ternary nanoparticles; this is followed by the galvanic displacement of Cu with Pt to generate a Pt monolayer on the surface of the core. The core-shell Pd1Ir1Ni2@Pt/C catalyst exhibits excellent oxygen reduction reaction activity, yielding a mass activity significantly higher than that of Pt monolayer catalysts containing PdIr or PdNi nanoparticles as cores and four times higher than that of a commercial Pt/C electrocatalyst. In 0.1 M HClO4, the half-wave potential reaches 0.91 V, about 30 mV higher than that of Pt/C. We verify the structure and composition of the carbon-supported PdIrNi nanoparticles using X-ray powder diffraction, X-ray photoelectron spectroscopy, thermogravimetry, transmission electron microscopy, and energy dispersive X-ray spectrometry, and we perform a stability test that confirms the excellent stability of our core-shell catalyst. We suggest that the porous structure resulting from the dissolution of Ni in the alloy nanoparticles may be the main reason for the catalyst’s enhanced performance.

Adsorbate-Induced Segregation of Cobalt from PtCo Nanoparticles: Modeling Au Doping and Core AuCo Alloying for the Improvement of Fuel Cell Cathode Catalysts

“…In addition, despite the apparent thermodynamic disadvantage over doping, many experimental techniques have in recent years been developed for monolayer deposition over the alloyed nanoparticle core, even for the cases where the elements of bigger atomic sizes and low surface energies such as gold were integral components of the alloy. Hence, the constructed alloy–core NPs are considered to make viable models of a possible geometric structure of the catalyst. ,− …”

Enhanced Performance of Sn@Pt Core-Shell Nanocatalysts Supported on Two Different Carbon Structures for the Hydrogen Oxidation Reaction in Acid Media

“…Pt-based core-shell nanocatalysts have probed a high catalytic activity for the ORR in acid media, employing plurimetallic, monometallic, or metal oxides cores such as Pd 3 Cu 1 , Ni, Ir, Co 3 O 4 , and Pd 1 Ir 1 Ni 2 , among others [8][9][10][11][12]. To the best of our knowledge, the assessment of catalytic activity of Pt-based core-shell nanocatalysts for the HOR in acid media is scarce.…”

High-Performance Core–Shell Catalyst with Nitride Nanoparticles as a Core: Well-Defined Titanium Copper Nitride Coated with an Atomic Pt Layer for the Oxygen Reduction Reaction

“…Compared with our previously reported TiNiN@Pt catalyst without nitride CNTs as the support, the mass activity of Ti 0.9 Cu 0.1 N@Pt/NCNTs was enhanced by ∼25%, indicating the significant improvement caused by the introduction of NCNTs as the support. Furthermore, the Pt mass activity of our Ti 0.9 Cu 0.1 N@Pt/NCNTs is ∼20% higher than those of the state-of-the-art M@Pt nanocatalysts (M = Pd, ,,,, Ru, ,, or Au , ). If we take into account the mass activity of all the precious metals, the activity of our catalyst is 2–4 times higher than that of the catalyst with precious metals as cores (Table S1).…”