Delocalized Electron Engineering of MXene-Immobilized Atomic Catalysts toward Fast Desolvation and Dendritic Inhibition for Low-Temperature Zn Metal Batteries.

Zhang, Jing; Pan, Lu; Jia, Lujie; Dong, Jing; You, Caiyin; Han, Chenxiao; Tian, Na; Cheng, Xiaomin et al. · Nano Lett · 2025

basic_science · Level V

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Abstract

Rechargeable low-temperature aqueous zinc metal batteries (LT-AZMBs) are considered as a competitive candidate for next-generation energy storage systems owing to increased safety and low cost. Unfortunately, sluggish desolvation kinetics of hydrated [Zn(H<sub>2</sub>O)<sub><i>x</i></sub>]<sup>2+</sup> and inhomogeneous ion flux cause detrimental hydrogen evolution reactions (HER) and Zn dendrite growth. Herein, the atomic iron well-implanted onto MXene via defect capture (SAFe@MXene) has been initially proposed to modulate Zn plating. The SAFe@MXene serves as kinetic promoters to enhance interfacial desolvation of [Zn(H<sub>2</sub>O)<sub><i>x</i></sub>]<sup>2+</sup> to prevent HER and uniformizes Zn<sup>2+</sup> flux for smooth deposition, as confirmed by theoretical simulation, Raman and electrochemical tests. Consequently, under 0 °C, the SAFe@MXene-modulated Zn electrodes deliver long-term stability of 800 h with lower overpotentials even at 5 mA cm<sup>-2</sup> or higher plating/stripping capacity. The full cell with a MnO<sub>2</sub> cathode stabilizes a high capacity-retention of nearly 100% after 1000 cycles at 1 A g<sup>-1</sup>, suggesting great promise for high-performance LT-AZMBs.