Hierarchical 2D sheets of N and S co-doped Fe-based electrocatalyst for efficient oxygen reduction in advanced Zn-air battery

Abstract

Currently, the scientific community is keenly interested in the design and production of efficient and durable transition metal electrocatalysts for oxygen reduction reactions (ORR). Therefore, this study reports a simple and reproducible N and S co-doped two-dimensional (2D) hierarchical porous electrocatalyst is reported. NSC the support material first was obtained by pyrolyzing trithiocyanuric acid (TTCA) and loaded on hemin to obtain the final material named Fe/NSC-800. 2D hierarchical porous structures with the large specific surface area were constructed by using TTCA as the template, S source, and additional N source. The addition of hemin not only retained the morphology of the NSC but also provided source of Fe for Fe/NSC-800. The Fe/NSC-800 possessed the limiting current density of 5.85 mA cm–2 and good ORR stability in 0.1 M KOH solution. Based on the excellent ORR performance of Fe/NSC-800, it was assembled into the primary Zn-air battery, which also exhibited satisfactory open circuit voltage (1.55 V) and energy density (880 W h kg–1). This work has contributed to the rational engineering and fabrication of high-performance ORR electrocatalysts for Zn-air battery applications.