Constructing delocalized electronic structures to motivate the oxygen reduction activity of zinc selenide for high-performance zinc-air battery

Abstract

Rechargeable zinc-air battery (ZAB) typically necessitates highly efficient, durable, and cost-effective electrocatalysts to accelerate oxygen reduction reaction (ORR). Zinc selenide (ZnSe) has been demonstrated as a superior energy storage material due to its unique electronic structure for various energy-related applications but is still rarely developed in electrocatalysis field. Herein, the efficient interfacial engineering is reported to motivate and sufficiently boost the ORR performances of ZnSe to an unprecedented level. Density functional theory (DFT) calculations demonstrate that the introduction of robust Se-C interactions and N species regulation could efficiently modulate the local electronic structure of ZnSe and improve the interaction with oxygen-containing intermediate, thus producing lower reaction energy barrier of O2 → OOH* conversion. The optimized ZnSe@PNC catalyst manifests remarkable ORR activity with a half-wave potential of 0.905 VRHE in alkaline. Furthermore, the assembled Zn-air batteries with ZnSe@PNC cathodes show large peak power density (126 mW cm−2), high specific capacity (818 mAh/g) and long cycling life (200 h). This work provides more possibilities for the electrocatalytic applications of nonprecious metal selenide electrocatalyst for future energy storage.