J. Mater. Sci. Technol. ›› 2025, Vol. 222: 1-10.DOI: 10.1016/j.jmst.2024.09.046

• Research Article •     Next Articles

In-situ nitrogen-doped carbon nanotube-encapsulated Co9S8 nanoparticles as self-supporting bifunctional air electrodes for zinc-air batteries

Qihao Wua, Heju Gaoa, Jiahui Jianga, Ting Zhaoa, Shuai Liua, Chunyan Wua, Guancheng Xua,*, Li Zhanga,b,*   

  1. aState Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830046, China;
    bCollege of Chemical Engineering, Xinjiang University, Urumqi 830046, China
  • Received:2024-07-14 Revised:2024-09-04 Accepted:2024-09-09 Published:2025-07-01 Online:2024-11-01
  • Contact: * E-mail addresses: xuguanchengxju@163.com (G. Xu), zhangli420@xju.edu.cn (L. Zhang) .

Abstract: A flexible air electrode with excellent activity and stability is essential for flexible zinc-air batteries. In this study, we report the rational design of nitrogen-doped carbon nanotube-encapsulated Co9S8 nanoparticles on carbon cloth (Co9S8/NCNTs/CC), serving as self-supporting air electrodes for both liquid-state and flexible zinc-air batteries. The Co9S8/NCNTs/CC-1 exhibited a half-wave potential of 0.86 V for oxygen reduction reaction (ORR) and achieved a current density of 10 mA cm-2 for oxygen evolution reaction (OER) at a voltage of only 1.52 V. The well-constructed nanotube on carbon cloth facilitates mass diffusion and electron transfer, while enhancing the mechanical flexibility of the material. Density functional theory (DFT) calculations suggested that the synergistic interaction between Co9S8 and NCNTs effectively enhanced the bifunctional electrocatalytic performance of the material. Liquid-state and flexible zinc-air batteries assembled with Co9S8/NCNTs/CC-1 demonstrated outstanding charge-discharge capabilities and long-term stability.

Key words: Co9S8 nanoparticles, N-doped carbon nanotube, Bifunctional electrocatalyst, Self-supporting electrode, Flexible zinc-air batteries