One-pot synthesis of platinum3cobalt nanoflowers with enhanced oxygen reduction and methanol oxidation

Abstract

Herein, a simple one-pot approach is developed for preparation of Pt3Co nanoflowers by co-reduction of Pt (II) acetylacetonate (Pt(acac)2) and Co (III) acetylacetonate (Co(acac)3) in oleylamine, without any seed or template. It is found that hexadecylpyridinium chloride monohydrate (HDPC) is served as both the stabilizing and structuring-directing agent that plays an important role in the formation of well-dispersed flower-like Pt3Co nanoparticles. The as-prepared Pt3Co nanoflowers show the enhanced catalytic performance for oxygen reduction reaction (ORR) in comparison with solid Pt3Co nanoparticles and commercial Pt black catalysts, dominated by a four-electron pathway based on the Koutecky–Levich equation. Meanwhile, Pt3Co nanoflowers exhibit the improved catalytic activity and long-term stability towards methanol oxidation reaction (MOR), using solid Pt3Co nanoparticles and commercial Pt black catalysts as references. The improved catalytic features of Pt3Co nanoflowers are mainly attributed to the porous three-dimensionally interconnected structures, enlarged specific surface area, ligand effect and bifunctional mechanism between Pt and Co. The as-developed method provides a promising pathway for preparation of highly efficient electrocatalysts for ORR and MOR.