Reviving Zn0 Dendrites to Electroactive Zn2+ by Mesoporous MXene with Active Edge Sites

作者：Fanxing Bu, Zhihao Sun, Wanhai Zhou, Yanyan Zhang, Yongjin Chen, Bing Ma, Xiaoxu Liu, Pei Liang, Chenglin Zhong, Ruizheng Zhao, Hongpeng Li, Lipeng Wang, Tengsheng Zhang, Boya Wang, Zaiwang Zhao, Jie Zhang, Wei Li, Yasseen S. Ibrahim, Yasser A. Hassan, Ahmed A. Elzatahry, Dongliang Chao, Dongyuan Zhao · 发表于：Journal of the American Chemical Society · 年份：2023 · DOI：10.1021/jacs.3c08986 · 被引用次数：174 · 研究领域：Advanced battery technologies research、MXene and MAX Phase Materials、Advanced Battery Materials and Technologies

Zinc metal-based aqueous batteries (ZABs) offer a sustainable, affordable, and safe energy storage alternative to lithium, yet inevitable dendrite formation impedes their wide use, especially under long-term and high-rate cycles. How the battery can survive after dendrite formation remains an open question. Here, we pivot from conventional Zn dendrite growth suppression strategies, introducing proactive dendrite-digesting chemistry via a mesoporous Ti 3 C 2 MXene (MesoTi 3 C 2 )-wrapped polypropylene separator. Spectroscopic characterizations and electrochemical evaluation demonstrate that MesoTi 3 C 2, acting as an oxidant, can revive the formed dead Zn 0 dendrites into electroactive Zn 2+ ions through a spontaneous redox process. Density functional theory reveals that the abundant edge-Ti–O sites in our MesoTi 3 C 2 facilitate high oxidizability and electron transfer from Zn 0 dendrites compared to their in-plane counterparts. The resultant asymmetrical cell demonstrates remarkable ultralong cycle life of 2200 h at a practical current of 5 mA cm –2 with a low overpotential (<50 mV). The study reveals the unexpected edge effect of mesoporous MXenes and uncovers a new proactive dendrite-digesting chemistry to survive ZABs, albeit with inevitable dendrite formation.