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  • Colloidal synthesis of monodisperse trimetallic Pt–Fe–Ni nanocrystals and their enhanced electrochemical performances
Title: Colloidal synthesis of monodisperse trimetallic Pt–Fe–Ni nanocrystals and their enhanced electrochemical performances
Abstract Among the multi-metallic nanocatalysts, Pt-based alloy nanocrystals (NCs) have demonstrated promising performance in fuel cells and water electrolyzers. Herein, we demonstrate a facile colloidal synthesis of monodisperse trimetallic Pt–Fe–Ni alloy NCs through a co-reduction of metal precursors. The as-synthesized ternary NCs exhibit superior mass and specific activities toward oxygen reduction reaction (ORR), which are ∼2.8 and 5.6 times as high as those of the benchmark Pt/C catalyst, respectively. The ORR activity of the carbon-supported Pt–Fe–Ni nanocatalyst is persistently retained after the durability test. Owing to the incorporation of Fe and Ni atoms into the Pt lattice, the as-prepared trimetallic Pt-alloy electrocatalyst also manifestly enhances the electrochemical activity and durability toward the oxygen evolution reaction with a reduced overpotential when compared with that of the benchmark Pt/C (△ η = 0.20 V, at 10 mA cm −2 ). This synthetic strategy paves the way for improving the reactivity for a broad range of electrocatalytic applications.  more » « less
Award ID(s):
1808383
NSF-PAR ID:
10402781
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Nanotechnology
Volume:
34
Issue:
7
ISSN:
0957-4484
Page Range / eLocation ID:
075401
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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