Revealing the Stabilization Mechanism of Electron-Enriched PtNiCo Catalysts in Practical Direct Methanol Fuel Cells

Abstract

The rational design of Pt-based alloy catalysts with dual resistance to CO poisoning and metal leaching, enabled by interfacial electronic modulation, remains a critical challenge for practical direct methanol fuel cells (DMFCs). Here, we report a highly stable catalyst comprising electron-enriched TiN-meditated PtNiCo (denoted as e-PtNiCo) for DMFCs, demonstrating stabilization mechanisms rooted in enhanced Pt-CO antibonding interactions and strengthened Pt–Co/Ni chemical bonds. The e-PtNiCo catalyst exhibits a voltage decay of 9.6% at 100 mA cm^–2 over 50 h under practical DMFC operating conditions─a 4-fold improvement compared with the benchmarked PtNiCo (37.7%). Density functional theory calculations and post-mortem elemental analysis reveal that the developed catalysts possess tailored *CO adsorption energetics (−1.62 eV vs −1.27 eV for carbon-supported counterparts) and a 2-fold reduction in Ni/Co dissolution, governed by robust metal–support electronic coupling. This work establishes a mechanistic framework linking support-induced electronic effects to the stability of Pt-based alloys, offering a generalizable strategy for designing structurally durable, high-performance electrocatalysts in energy conversion technologies.

A remarkably stable catalyst comprises electron-enriched TiN-meditated PtNiCo, exhibiting both excellent CO-tolerance and metal leaching resistance for practical direct methanol fuel cells.