Atomically dispersed Fe-Ni dual sites in heteroatom doped carbon tyres for efficient oxygen electrocatalysis in rechargeable Zn-Air battery

The electronic and functional synergies between the twin metal centers make dual single-atom catalysts (DACs) attractive for oxygen electrocatalysis. The catalytic activities of DACs are largely decided by their surrounding micro-environment and supporting substrates. Modulating the micro-environment as well as engineering the efficient support is challenging tasks. Moreover, both are critical to optimizing the per-formance of DACs. Herein, a novel bio-cooperative strategy is developed to synthesize FeNi-DAC wherein Fe-Ni dual-atom sites are embedded in the N, P codoped tyre shaped carbon matrix. The configuration matching of Fe-Ni dual centers together with the local electronic engineering of N, P heteroatoms syner-gistically boost the catalytic activity on the oxygen reaction. Furthermore, the central-hollow highly -porous carbon matrix not only gives rise to a large amount of active sites, but also facilitates fast kinetics. Taking advantage of both the DAC and the substrate, the FeNi-NPC hollow tyre (HT) catalyst scores high in both oxygen reduction and evolution reactions, which exhibits the narrow potential difference and excellent durability. The aqueous Zn-air full battery (ZAB) integrating the FeNi-NPC HT air cathode has a high power density and a good stability over long-term cycling. Moreover, the flexible solid-state ZAB assembled with the polymer electrolyte obtains the high reliability over a wide range of tempera-tures or under diverse outside deformations. Therefore, this work offers a new green approach to prepare highly efficient DACs with built-in modulated micro-environment and tailor-made substrates. Moreover, it also paves a new way to develop highly-pliable power source for flexible electronics. (c) 2023 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

This paper introduces a novel bio-cooperative strategy for synthesizing FeNi-DAC catalyst, which exhibits high catalytic activity and good stability in oxygen electrocatalysis. The catalyst has optimized micro-environment and tailor-made substrates, providing a new green approach for preparing highly efficient DACs.