Affiliation: | 1. Key Laboratory of Luminescent and Real-Time Analytical Chemistry, (Southwest University), Ministry of Education, School of Materials & Energy, Southwest University, Chongqing, 400715 P.R. China Institution Chongqing Key Lab for Advanced Materials and Clean Energies of Technologies, School of Materials and Energy, Southwest University, Chongqing, 400715 P.R. China;2. Key Laboratory of Luminescent and Real-Time Analytical Chemistry, (Southwest University), Ministry of Education, School of Materials & Energy, Southwest University, Chongqing, 400715 P.R. China |
Abstract: | It remains challenging to rationally synthesize iron/nitrogen-doped carbon (Fe/N-C) catalysts with rich Fe−Nx atomic active sites for improved oxygen reduction reaction (ORR) electrocatalysis. A highly efficient Fe/N-C catalyst, which has been synthesized through a spatial isolation strategy, is reported. Derived from bioinspired polydopamine (PDA)-based hybrid microsphere precursors, it is a multifunctional carrier that loads atomically dispersed Fe3+/Zn2+ ions through coordination interactions and N-rich melamine through electrostatic attraction and covalent bonding. The Zn2+ ions and melamine in the precursor efficiently isolate Fe3+ atoms upon pyrolysis to form rich Fe−Nx atomic active sites, and generate abundant micropores during high-temperature treatment; as a consequence, the resultant Fe-N/C catalyst contains rich catalytically active Fe−Nx sites and a hierarchical porous structure. The catalyst exhibits improved ORR activity that is superior to and close to that of Pt/C in alkaline and acidic solutions, respectively. |