Regeneration of single-atom catalysts deactivated under acid oxygen reduction reaction conditions

Single-atom catalysts serve as a promising candidate to realize noble-metal-free electrocatalytic oxygen reduction in acid media. However, their poor stability under working conditions strictly restrains their practical applications. Therefore, regeneration of their electrocatalytic activity is of great significance. Herein, the regeneration of a Fe-N-C single-atom catalyst is demonstrated to be feasible by a facile annealing regeneration strategy. The activity after regeneration recovers to that of the pristine electrocatalyst and surpasses the deactivated electrocatalyst. The regeneration mechanism is identified to be selfetching of the surface carbon layer and consequent exposure of the previously buried single-atom sites. Furthermore, the regeneration strategy is applicable to other single-atom catalysts. This work demonstrates the feasibility of regenerating oxygen reduction electrocatalysts and affords a pioneering approach to deal with rapid deactivation under working conditions.@2022 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

The regeneration of single-atom catalysts, such as Fe-N-C, is feasible through a facile annealing regeneration strategy, allowing the recovered activity to surpass that of the deactivated catalyst. This pioneering approach of selfetching the surface carbon layer to expose buried single-atom sites shows promise in addressing rapid deactivation under working conditions.