Liquid-Phase Templateless Synthesis of Pt-on-Pd_0.85Bi_0.15 Nanowires and PtPdBi Porous Nanoparticles with Superior Electrocatalytic Activity

This article reports the synthesis of Pt-on-Pd 0.85 Bi 0.15 nanowires (NWs) and PtPdBi porous nanoparticles (PNPs) by a facile, one-pot, wet-chemical, and templateless method in the presence of oleylamine (OAm) and NH 4 Br. The relationship between the morphology and composition in the PtPdBi trimetallic system was systematically studied. Interestingly, it is verified that adding only 5% Bi will produce Pd NWs, which offers a novel approach to synthesize Pd NWs in the oil phase without any template. On the basis of the fact of synthesizing Pd 0.85 Bi 0.15 NWs, Pt-on-Pd 0.85 Bi 0.15 NWs with hetero-nanostructures were successfully synthesized by a one-step method. Furthermore, the number of Pt nanobranches for Pt-on-Pd 0.85 Bi 0.15 NWs could be easily controlled via simply changing the synthetic parameters, which could tune the catalytic properties. PtPdBi PNPs were obtained by the acid pickling of PtPdBi 2 intermetallic compounds. Most importantly, a catalytic study indicates that the as-obtained Pt-on-Pd 0.85 Bi 0.15 NWs and PtPdBi PNPs exhibited much higher electrocatalytic activity and durability for the oxygen reduction reaction (ORR) than the commercial Pt/C catalyst. We expect that this work will provide a promising strategy for the development of efficient ORR electrocatalysts and can also be extended to the preparation of other nanowires or hetero-nanostructures with desirable functions.