Cobalt ferrite on honeycomb-like algae-derived nitrogen-doped carbon for electrocatalytic oxygen reduction and ultra-cycle-stable lithium storage

摘要

Oxygen reduction reaction (ORR) and Lithium storage both play the key roles in energy conversion and storage devices. Here, we report a honeycomb-like nitrogen-doped carbon derived from enteromorpha algae (N-EA), using a one-step pyrolysis process at only 600 degrees C to simultaneously achieve doping, carbonization and activation. After anchoring CoFe2O4 on N-EA, CoFe2O4/N-EA, not only inherits the high surface area, porous structure, active nitrogen species from N-EA, but also benefits from the active sites and high theoretical specific capacity of Li storage from CoFe2O4. The synergistic effect makes CoFe2O4/N-EA an alternative catalyst to commercial Pt/C for ORR with superior activity and stability. Moreover, CoFe2O4/N-EA exhibits a remarkable cycle performance with a 100% capacity retention (similar to 900mAh g(-1)) after 500 cycles at 0.5 A g(-1). Green preparation, waste utilization, good ORR performance and Li storage property of CoFe2O4/N-EA could make it a promising candidate for fuel cells and LIBs. (C) 2018 Elsevier Ltd. All rights reserved.