Rational design ternary platinum based electrocatalysts for effective methanol oxidation reaction

Abstract

Exploring effective, durable, and affordable electrocatalysts of methanol oxidation reaction (MOR) is of vital significance for the industrial application of direct methanol fuel cells. Herein, an efficient, general, and expandable method is developed to synthesis two-dimensional (2D) ternary PtBiM nanoplates (NPLs), in which various M (Co, Ni, Cu, Zn, Sn) is severed as the third component to the binary PtBi system. The MOR performance of PtBiM NPLs is entirely investigated, demonstrating that both the MOR activity and durability is enhanced with the introduction of the additional composition. Pt3Bi3Zn NPLs shows much higher MOR activity and stability than that of the PtBi counterparts, not to mention the current advanced PtRu/C and Pt/C catalysts. The prominent performances are attributed to the modulated electronic structure of the surface Pt in PtBi NPLs by the addition of Zn, resulting in a weakened affination between Pt and the adsorbed poisoning species (mainly CO) compared with PtBi NPLs, verified by density functional theory (DFT) calculations. In addition, the absorbed OH can be generated on the surface of Zn atom due to its favorable water activation properties, thus the CO removal on the adjacent Pt atoms is accelerated, further leading to a high activity and anti-poisoning performance of the resulting Pt3Bi3Zn catalyst. This work provides new insights and robust strategy for highly efficient MOR electrocatalyst with extraordinary anti-poisoning performance and stability.