Carbon black supported PtCu nanoparticles derived from mix‐phased Cu precursor for high‐performanced oxygen reduction reaction in acid medium

Abstract

Alloying high‐cost Pt with transition metals has been considered as an effective route to synthesize the electrocatalysts with low Pt loading and excellent activity towards oxygen reduction reaction (ORR) under acid solution. The galvanic replacement method, as featured with efficiency and simplicity, is widely reported to produce Pt‐based bimetallic alloys and thereby declare the significance of reductive transition metal precursor on the enhancement of ORR performance. Herein, mix‐phased Cu−Cu2O precursor was applied to prepare carbon black supported highly dispersed PtCu alloy nanoparticles (PtCu/C). The proper Cu−Cu2O ratios can exactly facilitate the generation of small sized PtCu alloy nanoparticles with regulated bimetallic content. Meanwhile, the Cu2O phase is revealed to benefit the electron transfer from Pt to Cu and thus improve the intrinsic activity of Pt active sites. And the metallic Cu can favor the promotion of electrochemical active surface area. Consequently, the as‐prepared PtCu/C behaves impressive ORR activity with half‐wave potential of 0.88 V (vs. RHE) and mass activity of 0.49 A cm−2 mgPt−1 at 0.8 V, which is 9.8 times of commercial Pt/C catalysts. Our work will offer helpful advices for the development and regulation of novel Pt‐based alloy materials towards diverse electrocatalysis.