Structural modulation of carbon-confined Pt-based catalysts with high-dispersed controllable tri-heterointerface and their MOR performance

The development of carbon-supported Pt-based electrocatalysts that exhibit low Pt usage, high electrocatalytic activity, exceptional stability, and robust toxicity resistance is pivotal for the widespread adoption of Direct Methanol Fuel Cells (DMFCs). In this study, we successfully prepared porous carbon-supported Pt-based catalysts, PtCoFe-CoFeO_x@NPC, featuring carbon-confined with controllable tri-heterointerface through a process involving high-temperature induced phase migration and chemical replacement. Under the optimal conditions, the catalyst PtCoFe-CoFeO_x@NPC for methanol oxidation reaction exhibits the catalytic activity of 960 mA·mg_Pt⁻¹, which is 3.7 times that of commercial Pt/C (255 mA·mg_Pt⁻¹) and 1.9 times that of commercial PtRu/C (506 mA·mg_Pt⁻¹). The alloyed active centers improve the catalytic activity towards MOR. The controlled tri-heterointerfaces rapidly release Pt active sites, increasing the electron transfer rate, and significantly enhancing MOR activity. The carbon-confined structure achieved high dispersion of active centers and effectively prevented Pt loss, improving catalytic activity and stability. These advantages synergistically improve the MOR performance of Pt-based catalysts.