PdM (M = Fe, Co, Ni) bimetallic nanowires enhances oxygen reduction catalysis in acid medium

The preparation of platinum-free electrocatalysts with ideal oxygen reduction reaction (ORR) activity is of great significance for cost-effective fuel cells. Herein, we synthesize a series of Pd-based (PdFe, PdCo, PdNi, and Pd) nanowires (PdM NWs). Their diameters are about 10 nm. And the lengths are up to even micrometers. The mass activity of the series of Pd-based catalysts followed the descending order: PdNi NWs/C > commercial Pt/C > PdCo NWs/C > PdFe NWs/C > pure Pd NWs/C. The optimal half-wave (E 1/2 ) of PdNi NWs/C (839 mV) is positive shift 138 and 25 mV compared with pure Pd NWs/C (701 mV) and commercial Pt/C (814 mV), respectively. The mass activity (MA) of PdNi NWs/C only dropped 28% after 10,000 potential cycles between 0.6 and 1.1 V versus RHE in acid medium. This work provides a promising and reliable strategy to synthesize high performance Pd-based electrocatalyst, which is promising alternative to expensive Pt-based electrocatalysts for fuel cells. Graphical Abstract TOC: We prepared bimetallic PdNi nanowires, which ORR mass activity higher than pure Pd nanowires and commercial Pt/C in acidic medium.