Boosting the Performance of Pt/C Catalysts via Nitrogen-Doped Carbon Support: Insights from Structural and...

Nitrogen-doped carbon supports enhance platinum electrocatalysts for proton exchange membrane fuel cells (PEMFCs). This study demonstrates a rapid melamine-assisted N-doping method for conductive carbon black (Ketjenblack EC600JD), producing a high-loading (≈40 wt.% Pt) catalyst with exceptional activity and durability. X-ray photoelectron spectroscopy confirms successful N-incorporation. Microscopy reveals uniform Pt nanoparticles (2.5-3 nm) and atomic Pt clusters on the N-doped support, attributed to strong Pt-N interactions. Density functional theory (DFT) calculations highlight the critical role of pyridinic-N defects in stabilizing atomic Pt, enhancing activity via charge transfer, and improving stability via strong Pt anchoring. Electrochemically, Pt/KB-600-N achieves twice the mass activity of commercial HiSPEC4000. After accelerated stress testing, it shows only a 15% electrochemical surface area (ESA) loss versus 35% for undoped Pt/KB-600. Enhanced stability correlates with pyridinic/graphitic N species mitigating carbon corrosion and Pt detachment. Binding energy analysis and cluster models quantify the Pt-support interaction, revealing N-doping increases Pt adhesion energy by 20-30% compared to pristine carbon. This work establishes a rational design strategy for high-performance Pt-based electrocatalysts by leveraging nitrogen-doped carbon supports, offering fundamental insights into the critical role of Pt-N interactions in enhancing both activity and durability for PEMFC applications.