Synthesis of Fe-doped carbon hybrid composed of CNT/flake-like carbon for catalyzing oxygen reduction

Carbon-based materials with tunable properties have emerged as promising candidates to replace Pt-based catalysts for accelerating oxygen reduction reaction (ORR) in fuel cells or metal-air batteries. In this work, we constructed a carbon hybrid which consists of one-dimensional (1D) carbon nanotubes and flake-like carbons by pyrolysis of leaf-like metal-organic frameworks. The optimal hybrid electrocatalyst of Fe_7%-L-CNT-900 possesses the desired features for ORR, including active Fe species, high degree of graphitization, large specific surface area, and hierarchical porous structures. Consequently, Fe_7%-L-CNT-900 performs a high electrocatalytic activity for ORR with a half-wave potential of 0.88 V, which is comparable to that of Pt/C (20 wt.%). This strategy provides an insight into the investigation of highly efficient and low-cost composite electrocatalyst for oxygen reduction reaction. [Figure not available: see fulltext.]