Octahedral PtCu alloy nanocrystals with high performance for oxygen reduction reaction and their enhanced stability by trace Au

• DOI: 10.1016/j.nanoen.2017.01.003
• Publication Date: 2017-01-05T13:39:41Z
• Authors: Bang-An Lu; Tian Sheng; Na Tian; Zong-Cheng Zhang; Chi Xiao; Zhen-Ming Cao; Hai-Bin Ma; Zhi-You Zhou; Shi-Gang Sun
• Keywords: Reducing agent

Abstract In fuel cell technologies, the sluggish kinetics of oxygen reduction reaction (ORR) on the cathode is the main obstacle, and it is thus urgent to develop high-performance catalysts. In this work, we have synthesized 10 nm-sized octahedral PtCu alloy nanocrystals by a simple one-pot strategy using I- as shape-directing agent instead of using large surfactants. The area specific activity and mass activity of the synthesized octahedral PtCu/C reach 4.25 mA cm−2 and 1.20 mA μgPt−1 at 0.90 V (vs RHE), respectively, which are 21.3 and 8.6 times higher than those of commercial Pt/C catalysts. Unexpectedly, we found that the stability of PtCu/C can be enhanced dramatically by doping trace Au (Au/Pt =0.0005). The mass activity loss of PtCuAu0.0005/C was only 8%, much smaller than those of PtCu/C (32%), and Pt/C (52%) after 10,000 potential cycles. This study provides a strategic design of Pt-based efficient ORR catalysts for fuel cells.