Boosting Oxygen Reduction Catalysis with Hierarchically Porous Fe-Doped Carbon by Chemical Vapor Deposition in Zn–Air Batteries

The effective application of Fe–N-doped carbon as an oxygen reduction reaction (ORR) electrocatalyst for advanced electrochemical devices has long been impeded by the design and preparation of high-performance electrodes. Herein, we developed a class of carbon-based electrocatalysts through a wet chemistry strategy and the chemical vapor deposition (CVD) method. A great deal of Zn species with a low boiling point evaporate outward to generate abundant micropores, while the Fe dopant is essential for constructing large-sized nanopores attributable to the Kirkendall effect. The CVD-assisted material possesses a higher quantity of uniformly distributed Fe–Nx active sites and a larger specific surface area with hierarchically porous nanostructures compared to the electrocatalyst prepared by the wet chemistry strategy. The resulting FeNC-CVD displays satisfactory electrocatalytic ORR performance with high half-wave potential (0.88 V), outperforming that of commercial Pt/C (0.86 V). As expected, the Zn–air batteries assembled by FeNC-CVD achieve an outstanding peak power density and robust discharge platforms, manifesting the bright application prospect of the attractive electrocatalyst in advanced energy devices. This work may provide new perception on boosting the rational design and indepth understanding of CVD-assisted materials.