Reinforcing the Chemical Bonding in Pt 3 Ni Catalysts via Metallic Interface‐Directed Activation for Durable Fuel Cells

Abstract Pt–Ni alloys are widely recognized as the most promising catalysts for the oxygen reduction reaction in proton exchange membrane fuel cells. However, the practical application of Pt–Ni catalysts is hindered by their limited durability, predominantly attributed to Ni corrosion and particle agglomeration. Herein, a metallic Pt–Ti interface (i.e., Pt 3 Ni/TiN) with directed fast electron pathways is proposed and constructed to effectively reinforce the Pt─Ni bonding strength and suppress Ostwald ripening. The distinctive interface of Pt 3 Ni/TiN demonstrates a remarkable 7.2‐fold decrease in Ni dissolution and minimal change in average particle diameter compared to its carbon‐supported counterpart (Pt 3 Ni/C) following accelerated durability testing. Moreover, the fabricated Pt 3 Ni/TiN catalyst exhibits a notable 78% retention in mass activity after aggressive square‐wave potential cycling, meeting the US Department of Energy's 2025 targets. This study provides a promising strategy for enhancing the durability of Pt–based catalysts through deliberate manipulation of interface properties.