Atomically Dispersed Fe on Nanosheet-linked, Defect-rich, Highly N-Doped 3D Porous Carbon for Efficient Oxygen Reduction

摘要

Exploring cost-effective and high-performance oxygen reduction reaction(ORR)electrocatalysts to replace precious platinum-based materials is crucial for developing electrochemic al energy conversion devices but remains a great challenge.Herein,Fe single atoms anchored on nanosheet-linked,defect-rich,highly N-doped 3D porous carbon(Fe-SAs/NLPC)electrocatalysts wer obtained by pyrolyzing saltsealed Fe-doped zeolitic imidazolate frameworks(ZIFs).NaCl functions both as pore-forming agent and closed nanoreactor,which can not only lead to the formation of defects-rich three-dimensional interconnected structures with high N-doping content to expose abundant active sites,promote mass transfer and electron transfer,but also facilitate the effective incorporation of Fe to form Fe-N,active sites without aggregation.These unique characteristics render Fe-SAs/NLPC outstanding electrocatalytic activity for ORR,with one-set potential of 0.96V and high kinetic current density(jK)of 33.32mA/cm^2 in alkaline medium,which surpass the values of most nonprecious-metal catalysts and even commercial Pt/C.