Aerophilic Triphase Interface Tuned by Carbon Dots Driving Durable and Flexible Rechargeable Zn-Air Batteries

Kuixing Ding; Yu Ye; Jiugang Hu; Liming Zhao; Wei Jin; Jia Luo; Shan Cai; Baicheng Weng; Guoqiang Zou; Hongshuai Hou; Xiaobo Ji

doi:10.1007/s40820-022-00994-3

Aerophilic Triphase Interface Tuned by Carbon Dots Driving Durable and Flexible Rechargeable Zn-Air Batteries

Nanomicro Lett. 2023 Jan 3;15(1):28. doi: 10.1007/s40820-022-00994-3.

Authors

Kuixing Ding^#¹, Yu Ye^#¹, Jiugang Hu², Liming Zhao³, Wei Jin⁴, Jia Luo¹, Shan Cai¹, Baicheng Weng¹, Guoqiang Zou¹, Hongshuai Hou⁵, Xiaobo Ji¹

Affiliations

¹ College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, People's Republic of China.
² College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, People's Republic of China. hujiugang@csu.edu.cn.
³ College of Standardization, China Jiliang University, Hangzhou, 310018, People's Republic of China.
⁴ School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, People's Republic of China.
⁵ College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, People's Republic of China. hs-hou@csu.edu.cn.

^# Contributed equally.

Abstract

Efficient bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are vital for rechargeable Zn-air batteries (ZABs). Herein, an oxygen-respirable sponge-like Co@C-O-Cs catalyst with oxygen-rich active sites was designed and constructed for both ORR and OER by a facile carbon dot-assisted strategy. The aerophilic triphase interface of Co@C-O-Cs cathode efficiently boosts oxygen diffusion and transfer. The theoretical calculations and experimental studies revealed that the Co-C-COC active sites can redistribute the local charge density and lower the reaction energy barrier. The Co@C-O-Cs catalyst displays superior bifunctional catalytic activities with a half-wave potential of 0.82 V for ORR and an ultralow overpotential of 294 mV at 10 mA cm^-2 for OER. Moreover, it can drive the liquid ZABs with high peak power density (106.4 mW cm^-2), specific capacity (720.7 mAh g^-1), outstanding long-term cycle stability (over 750 cycles at 10 mA cm^-2), and exhibits excellent feasibility in flexible all-solid-state ZABs. These findings provide new insights into the rational design of efficient bifunctional oxygen catalysts in rechargeable metal-air batteries.

Keywords: Aerophilic triphase interface; Bifunctional oxygen catalyst; Flexible rechargeable Zn-air battery; O2 diffusion; Oxygen-rich active sites.