Long-Range Regulation of Se Doping for Oxygen Reduction of Atomically Dispersed Sb Catalysts for Ultralow-Temperature Solid-State Zn-Air Batteries

Regulating the p-orbital valence electrons of atomicallydispersedmain-group metals to improve the inherent electrocatalytic activityhas attracted extensive concerns. Herein, we designed and synthesizedan atomically dispersed Sb-SeNC catalyst containing SbN2C2 and SeC2 structures, which have beenidentified by X-ray absorption spectroscopy and density functionaltheory (DFT) calculations. Sb-SeNC exhibits a high activityfor the oxygen reduction reaction (ORR), and a Sb-SeNC-basedflexible solid-state zinc-air battery (ZAB) can work efficientlyat -40 degrees C, with a peak power density of 54.1 mW cm(-2) and a rate discharge operation of about 44 h. DFTcalculations further confirm the long-range regulation mechanism ofthe SeC2 moiety for the ORR of SbN2C2 and obtain the volcano relationship of U-onset vs theSe-N distance. When the Se-N distance is 7.4 angstrom,the adsorption ability of active site Sb can be regulated to an optimalstate related to the RDS: *O -> *OH, while the smaller Se-Ndistance in short-range would lead to the excessive attenuation ofadsorption ability of active site and decrease of ORR activity, whichtherefore yields the long-range regulation effect of Se doping onthe ORR activity of SbN2C2. This long-rangeregulation strategy may provide a promising approach to boost thecatalytic activity of main-group metal catalysts to achieve its applicationin ultralow-temperature solid-state ZABs.

Automated summary

Regulating the p-orbital valence electrons of atomically dispersed main-group metals has attracted extensive attention for improving the inherent electrocatalytic activity. This study designed and synthesized an atomically dispersed Sb-SeNC catalyst containing SbN2C2 and SeC2 structures. This catalyst exhibited high activity for the oxygen reduction reaction (ORR) and a Sb-SeNC-based flexible solid-state zinc-air battery (ZAB) showed efficient operation at -40 degrees C. The long-range regulation effect of Se doping on the ORR activity of SbN2C2 was confirmed through DFT calculations.