Atomic layer deposition of Pt nanoparticles grown onto 3D B-doped graphene as an efficient ultra-low Pt loading catalyst layer for PEMFC

Proton exchange membrane fuel cell (PEMFC) with ultra-low Pt loading is highly desirable but confronts challenges of deficient activity and durability for practical application. Herein, we report a newly integrated catalyst layer based on 3D porous B-doped graphene (3D-PBG) with the atomic layer deposition of Pt (Pt/3D-PBG) for PEMFC, in which highly graphitized 3D-PBG not only provides a robust framework to support Pt but also B dopants further enhances the deposition of Pt and their electronic interaction, resulting in high-performance PEMFC at ultra-low Pt loading. The cell with Pt/3D-PBG at 80.0 μg_Pt cm^-2 as cathode delivers a maximum power density of 0.90 W cm^-2 (H₂/Air, 150.0 kPa) and exhibits high durability meeting the Department of Energy (DOE) 2025 technical targets, which has been rarely achieved in the previous reports. Additionally, theoretical calculations reveal that the BC₂O and BCO₂ dopants facilitate the adsorption of Pt precursors, generating more nucleation sites for Pt and the BC₂O, B₄C, and BC₃ dopants enhance the interfacial interaction between graphene and Pt and induce a downward shift in the d-band center of Pt, leading to the high activity and durability of Pt/3D-PBG as cathode. This work provides new highlights for developing an efficient catalyst layer with enhanced interaction between Pt and heteroatom-doped graphene with highly graphitic degree for ultra-low Pt loading PEMFC.