Viable construction of a hydrangea-like B/N co-doped carbon matrix with dual-metal magnetic nanoparticles for high-performance lithium-oxygen batteries

The development of magnetic carbonous composites for enhancing the performance of lithium-oxygen batteries continues to pose a significant challenge. In this study, we propose a facile approach without any template agent and surfactant to prepare a porous carbon matrix with discrete active FeCo-BN/C sites, achieving a total metal loading of ca. 4.67 at.%. This lightsome and magnetic composite exhibits a hydrangea-like hierarchical morphology and possesses key features essential for cathodic catalysis, including high catalytic activity and a large porous surface structure capable of accommodating abundant discharge products. Consequently, this interesting structure shows enhanced electrocatalytic activity and cyclic stability, surpassing that of commercial Pd/C catalyst. DFT calculations also revealed that the synergistic effect of dual-metal FeCo-N/C sites with B-doping coordination induced asymmetric charge distribution, amplifying the adsorption/desorption of oxygen intermediates. This work establishes a significant paradigm for the structural construction of hierarchical bimetal-BN/C catalysts tailored for air cathodes.