The synergistic effect of soft-hard template to in situ regulate mass transfer and defective sites of doped-carbon nanostructures for catalysis of oxygen reduction

Nitrogen-doped carbon materials are intensively investigated as electrocatalysts toward oxygen reduction reaction (ORR). The activity of the catalysts can be effectively boosted by regulating the microstructure to construct defective three-phase interface. Herein, an N-doped carbon-based porous catalyst (DT-Fe-N-C) is fabricated by a dual-template strategy with SiO2 and pluronic F127 as the hard and soft templates. Benefited from the modulation, the mesopore-dominated DT-Fe-N-C exhibits remarkable specific surface area (990.19 m2 g-1), high Fe-Nx content and plenty of defects. Resultantly, DT-Fe-N-C shows outstanding cat-alytic activity to ORR with 0.853 V of half-wave potential, high stability and selectivity to the four-electron ORR mechanism. The Zn-air battery with DT-Fe-N-C outputs 219 mW cm-2 of maximum power density, 861 Wh kgZn1 of specific energy density at 50 mA cm-2 and runs at a higher voltage than that of Pt/C-based battery. This work provides an avenue for the defect engineering in the design of non-precious metal ORR catalysts. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

In this study, an N-doped carbon-based porous catalyst with high specific surface area and abundant defects was fabricated using a dual-template strategy. The catalyst exhibited outstanding catalytic activity and stability in the oxygen reduction reaction. This work provides a new method for the design of non-precious metal ORR catalysts.