Titanium Nitride–Cellulose Nanofiber Composite Separator for Zn Anode Stability in Aqueous Batteries
Jingjing Niu, Jin Cao, Xueqin Zhang, Xueqin Zhang, Dongdong Zhang, Chengwu Yang, Kittima Lolupiman, Zhiyuan Zeng, Xinyu Zhang, Xinyu Zhang, Jiaqian Qin
Abstract
High Resolution Image Download MS PowerPoint Slide Aqueous zinc-ion batteries (ZIBs) face significant challenges of Zn dendrite formation, electrode passivation, and corrosion. Herein, we introduce a composite separator composed of titanium nitride (TiN) and cellulose nanofiber (CNF), termed TN5, designed to enhance the performance of ZIBs. The TN5 separator, with a thickness of approximately 45 μm, combines low cost, high thermal stability, and flexibility. Experimental and theoretical analyses demonstrate that the TN5 separator improves Zn 2+ ion diffusion and ensures uniform Zn plating, effectively mitigating dendrite and side reactions. Zn//Zn symmetric cells using the TN5 separator achieve exceptional cycling life spans of 2500 h at 0.5 mA cm –2 and 1000 h at 5 mA cm –2, significantly outperforming cells with CNF separators. Additionally, Zn//NVO full batteries with TN5 separators exhibit a superior discharge capacity and cycling stability. The enhanced performance is attributed to improved wettability, reduced concentration polarization, and the promotion of Zn (002) plane deposition. This study provides a comprehensive approach to developing high-performance, cost-effective separators for ZIBs, offering insights into the stabilization of Zn anodes and the advancement of aqueous zinc-ion battery technology.