Synergistically enhanced oxygen reduction electrocatalysis by atomically dispersed and nanoscaled Co species in three-dimensional mesoporous Co, N-codoped carbon nanosheets network

Abstract Metal-nitrogen-codoped carbon (M-N-C) nanostructures are promising electrocatalysts for oxygen reduction reaction (ORR). Despite the great progress that has been achieved, synthesizing three-dimensional porous nanoarchitectures derived from Co-N-C nanosheets or related nanohybrids with high content (> 5 wt%) of exposed single-atom sites remains a challenge. Herein, novel three-dimensional mesoporous Co-N-C nanosheets network enwrapping small amount of Co nanoparticles nanohybrids are fabricated by molten-salt template-assisted pyrolysis of Co-folic acid precursors and chemical etching. In the obtained nanohybrids, the content of single-atom-like Co (SA-Co%) is 7.4 wt%