Isolation anchoring strategy for in situ synthesis of iron single-atom catalysts towards long-term rechargeable zinc-air battery.

The reasonable design and construction of single-atom electrocatalysts with low-cost and excellent intrinsic activity for oxygen reduction reaction (ORR) is indispensable in metal-air batteries. Herein, a facile isolation anchoring strategy was reported for in situ formation of porous N-doped carbon catalysts (Fe 1 /NC) rich in Fe single atoms. The d -glucose, zinc gluconate and N-rich histidine were deployed as spatial isolation agents and anchoring agents to inhibit iron atom aggregation during the high-temperature pyrolysis. The as-synthesized Fe 1 /NC catalyst shows remarkable stability and superior ORR electrocatalytic activity under both alkaline and acidic conditions owing to highly dispersed Fe–N 4 sites, especially with a half-wave potential up to 0.91 V in 0.1 M KOH, exceeding 60 mV compared with Pt/C. Notably, the Fe 1 /NC-based Zn-air battery exhibits maximal power density of 164 mW cm−2, large specific capacities of 769 mA h g Zn −1, excellent cycle stability over 300 h, and great potential in renewable energy conversion electronics. A facile isolation anchoring strategy was reported to synthesize the Fe single-atom electrocatalyst that exhibits excellent ORR catalytic efficiency and long-term stability in both three electrodes system and zinc-air battery due to the abundant Fe–N 4 active sites. [Display omitted] • A facile isolation anchoring strategy was reported to prepare Fe single-atom electrocatalyst. • d -glucose, zinc gluconate and N-rich histidine were deployed as spatial isolation and anchoring agents. • The electrocatalysts exhibit superior ORR performance due to the abundant Fe–N 4 active sites. • The Zn-air battery assembled with Fe 1 /NC displays a high discharge specific capacity and excellent cyclic stability. [ABSTRACT FROM AUTHOR]