Heterogeneous fcc-Pt/hcp-PtBi Thick-Edge Nanoplates with Enhanced Activity for Formic Acid Oxidation

Rational design of Pt-based alloy electrocatalysts with heterostructures and 3D nanoplate morphology remains a great challenge. Herein, we advance a facile wet-chemical synthesis of heterogeneous fcc-Pt/hcp-PtBi thick-edge nanoplates (PtBi NPs) of 3.1 nm in thickness with a tunable edge width range from 3.7 to 7.0 nm. The preferential absorption of Br- ions and the excessive input of the Pt precursor play the crucial roles in the formation of the PtBi NPs. Owing to the unique structure and the heterogeneous feature, these PtBi NPs exhibited enhanced catalytic activity and stability for the oxidation of formic acid in comparison to commercial Pt/C. The best catalytic performance of Pt85Bi15 NPs demonstrated the existence of the synergistic effect between intermetallic hcp-PtBi and fcc-Pt.