Pt Nanoparticles on Graphene Doped by Boron Carbide With Strong Electronic Metal–Support Interaction for Efficient Ultra‐Low Pt Loading Proton Exchange Membrane Fuel Cells

ABSTRACT

Developing a durable cathode catalyst layer (CCL) with ultra‐low Pt loading <50 µg _Pt cm ⁻² for oxygen reduction reaction (ORR) is essential to substantially advancing the wide adoption of proton exchange membrane fuel cells (PEMFCs). Herein, a robust CCL was developed based on a 3D porous boron carbide‐doped graphene film synthesized by the arc discharge method as an integrated electrode framework. The specific boron carbide doping with B ₄ C and BC ₃ dopants endows graphene with a highly graphitic lattice and abundant electron‐deficient sites, which not only generates anchoring sites for the atomic layer deposition of highly dispersed Pt, but also induces strong electronic metal–support interactions via Pt (d _x ² , d _z ² )/B (p _x , p _y ) orbital hybridization with a downshift of the Pt d‐band center. As a result, the PEMFC with the CCL at 47.5 µg _Pt cm ⁻² delivers a high‐power density of 1.12 W·cm ⁻² (H ₂ /air at 150 kPa) with a 38% enhancement than that of the commercial Pt/C (200 µg _Pt cm ⁻² ) and an outstanding durability fully satisfying the 2025 technical targets of U.S. Department of Energy. This work provides a new approach of breaking the tradeoff between activity and durability for developing PEMFCs with <50 µg _Pt cm ⁻² via a strong electronic metal–support interaction.