Pumping Electrons from Oxygen-Bridged Cobalt for Low-Charging-Voltage Zn-Air Batteries

作者：Yuchao Wang, Q. X. Li, Meng Wang, Houzheng Ou, Danni Deng, Huanran Zheng, Yu Bai, Lirong Zheng, Zhiyan Chen, Weijie Li, Guozhao Fang, Yongpeng Lei · 发表于：Nano Letters · 年份：2024 · DOI：10.1021/acs.nanolett.4c03510 · 被引用次数：64 · 研究领域：Advanced battery technologies research、Advanced Battery Technologies Research、Electrocatalysts for Energy Conversion

Reducing the charging voltage is a prerequisite for improving the chargeability and energy efficiency of Zn-air batteries (ZABs). Herein, Fe 3+ pumps electrons from oxygen-bridged cobalt (Fe–O–Co) and induces the accelerated charging kinetics. For the liquid ZABs, a charging voltage of around 1.94 V at 10 mA cm –2 was displayed, which slightly increased 2% after continuous cycles for 180 h. A steady charging voltage of around 1.87 V at 10 mA cm –2 was also exhibited for quasi-solid-state ZABs. Control experiments and characterization show that the interactions between the O 2– and Fe 3+ sites are relatively weaker than those between the O 2– and Co 3+ sites. Compared with Mn 3+, Zn 2+, and Cu 2+, Fe 3+ effectively pumps electrons from Co sites to generate the active species for the oxygen evolution reaction. Thus, the deprotonation behavior and *OH conversion were improved. This work demonstrates the oxygen electron bridge modulated electron transfer between dual metal sites, contributing to the improvement of low-charging-voltage ZABs.