Worm-like PtCux alloys oriented by pyrolyzed alginic acid sodium with high performance in methanol electrooxidation

Abstract

Worm-like PtCux alloys were synthesized through the co-reduction of H2PtCl6 and CuCl2 in ethylene glycol under the orientation of pyrolyzed alginic acid sodium (PA), in order to disclose the growth mechanism of different metallic compounds. Through the characterizations of FTIR, Raman, XRD, XPS, TEM, etc., it illustrates that with the orientation of oxygen-containing functional groups in the support PA, the preferentially reduced Pt clusters accelerate the formation of metallic Cu clusters and then worm-like bimetallic PtCux alloys are generated with plenty of surface defects. The synthesized PtCu3/PA exhibits the highest content of metallic Pt0 (67.11 at%), the average width about 2.19 nm, the lattice strain of −1.18%, as well as the excellent performance for methanol electrooxidation. It has the best CO tolerance ability and the optimal mass activity of 1.922 A mgPt−1, which is more than four times of the commercial Pt/C. This work discloses an intriguing growth pathway of PtCux nanoparticles but also a facile route to synthesize bimetallic alloys with more electrocatalytic activity.