Revealing the Stabilization Mechanism of Electron-Enriched PtNiCo Catalysts in Practical Direct Methanol Fuel Cells.
Min Chen, Yichi Guan, Zhengpei Miao, Shuo Zhang, Chunxia Wu, Yu Zhou, Hongxian Luo, Daoxiong Wu, Ruisong Li, Junming Luo, Xinlong Tian
Abstract
Open AccessThe 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 conditionsa 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.