Templated-Assisted Synthesis of Structurally Ordered Intermetallic Pt3Co with Ultralow Loading Supported on 3D Porous Carbon for Oxygen Reduction Reaction

Abstract

Simple and reliable mass production of platinum-based alloy catalysts with excellent activity and stability is an enormous challenge for the wide commercialization of proton-exchange membrane fuel cells (PEMFC), especially those with ultralow loading of Pt. Herein, an economical, highly durable, and efficient catalyst consisting of structurally ordered intermetallic Pt₃Co alloy nanoparticles with ultralow Pt loading (1.4 wt %) supported on hierarchically porous carbon structure (three-dimensional, 3D Pt₃Co/C) were synthesized with large-scale production by the NaCl-template-assisted approach. The obtained best sample, 3D Pt₃Co/C#1, exhibited mass activities of 11.56 and 0.70 A mg_Pt^-1 for oxygen reduction reactions (ORRs) in alkaline and acidic electrolytes, which are 60.8 and 6.4 times those of commercial Pt/C, respectively. Furthermore, the 3D Pt₃Co/C#1 exhibited excellent stability both in acidic and alkaline electrolytes, with almost no decay of the half-wave potential after 5000 potential cycles. This work proposes a new high-yielding, simple, and environmentally friendly method to fabricate excellent Pt-based alloy electrocatalysts with ultralow loading of Pt, which opens up new hopes for the development of PEMFC.

Keywords: NaCl template; Pt3Co; oxygen reduction reaction; structurally ordered intermetallic; ultralow loading.