Engineering p–d Orbital Coupling and Vacancy-Rich Structure in Triatomic Iron–Bismuth–Iron Sites for Rechargeable Zinc–Air Batteries
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2025-04-29 |
| Journal | ACS Nano |
| Authors | Zhanhao Liang, Wencai Liu, Shaojie Jing, Yihui Huang, Bin Liao |
| Institutions | Chongqing University, Quantum Devices (United States) |
| Citations | 4 |
Abstract
Section titled “Abstract”The rational design of heteroatomic sites with synergistic electronic modulation remains a critical challenge for achieving bifunctional oxygen electrocatalysis in sustainable energy technologies such as fuel cells and metal-air batteries. Herein, a triatomic Fe<sub>2</sub>BiN<sub>5</sub> configuration embedded in nitrogen-doped carbon (Fe<sub>2</sub>BiN<sub>5</sub>/C) with atomically dispersed FeN<sub>2</sub>-BiN-FeN<sub>2</sub> sites and vacancy-rich structures is synthesized via a pyrolysis and etching strategy. The triatomic architecture endows Fe<sub>2</sub>BiN<sub>5</sub>/C with exceptional bifunctional activity, delivering a high oxygen reduction reaction half-wave potential of 0.918 V and an oxygen evolution reaction overpotential of 245 mV at 10 mA cm<sup>-2</sup>, surpassing Pt/C and RuO<sub>2</sub>. In situ X-ray absorption fine structure and Raman spectroscopy reveal dynamic structural evolution during electrocatalysis, where Fe acts as the primary active center with Bi regulating the electron distribution via long-range interactions, thereby optimizing adsorption/desorption energetics of oxygen intermediates. The theoretical calculations further elucidate that the Bi-induced p-d orbital coupling leads to the alteration in Fe d-orbitals energy level, downshift d-band center, weaken binding strength to the oxygen-based intermediates, and reduced energy barrier for oxygen electrocatalysis. This work provides an understanding of bifunctional triatomic site with p-block metal as electronic modulators embedded in transition-metal atoms toward enhanced oxygen catalysis.