Synergistic effects of N-doping and mesoporous structures in block copolymer-derived three-dimensionally ordered mesoporous carbon for PEMFC

Block copolymer (BCP) is a promising precursor to design ordered mesoporous carbon (OMC) materials for proton exchange membrane fuel cells due to its accessibility and controllability. However, enhancing the per-formance of OMCs through the integration of heteroatoms during the self-assembly process remains a chal-lenging endeavor. Herein, an ammonia-assisted pyrolysis method is used to deposit N atoms in self-assembled OMC (N-OMC). The resulting N-OMC exhibits a well-ordered mesoporous structure with the N content up to 6.43 at.%. Upon PtCo nanoparticles loading (PtCo/N-OMC), the PtCo/N-OMC demonstrates exceptional elec-trocatalytic activity, evidenced by a half-wave potential of 0.876 VRHE and an electrochemical surface area of 98.19 m2 center dot g- 1. The single-cell test confirms the superiority of the N-OMC structure, revealing a current density of 1.53 A center dot cm- 2 at 0.6 V and a peak power density of 1.17 W center dot cm- 2. Theoretical calculations affirm that the pyridinic N-doping reduces oxygen binding energy, thereby enhancing oxygen reduction reaction activity. The confine-ment effect of the mesopores avoids aggregation of nanoparticles, while doping-N-induced defects further bolster their electrochemical activities. This work highlights the synergistic effect of N-doping defects and ordered mesoporous architectures, illustrating the exceptional potential of the BCP-derived OMC as an ideal support for electrocatalysis applications.