Individually-atomic governing d—π* orbital interactions via Cu-promoted optimization of Fe-d band centers for high-efficiency zinc-air battery
Xinyan Zhou, Kexin Song, Feng Yu, Chao Jiang, Zhongjun Chen, Zizhun Wang, Nailin Yue, Xin Ge, Wei Zhang, Weitao Zheng
Abstract
It is challenging for precise governing of electronic configuration of the individually-atomic catalysts toward optimal electrocatalysis, as d-band configuration of a metal center determines the adsorption behavior of reactive species to the center in oxygen reduction reaction (ORR). The addition of Cu atom modifies the d-band center position of Fe central atom, thus strengthening the d—π* orbital interactions. Herein, FeCu-NC catalyst in the nitrogen-doped carbon (NC) support containing individual dual-metal CuN 4 /FeN 4 sites was prepared by the surface confinement strategy of zeolitic imidazolate framework (ZIF), treated as a model catalyst. Experimentally and theoretically co-verified dual-metal CuN 4 /FeN 4 sites highly dispersed in the NC support, enable transferring more electrons from FeN 4 sites to *OH intermediates, thereby accelerating the desorption process of *OH species. Superior to those commercial Pt/C, Our FeCu-NC catalyst exhibited extraordinary ORR activity (with a E 1/2 as high as 0.87 V) and cycling stability in 0.1 M KOH electrolyte, and thereof demonstrated excellent discharge performance in zinc-air batteries. Our construction of dual-atom catalysts (DACs) provides a strategy for atom-by-atom designing high-efficiency catalysts via orbital regulation.