Tailoring Nitrogen Terminals on MXene Enables Fast Charging and Stable Cycling Na-Ion Batteries at Low Temperature
Xia Yang, Lan‐Fang Que, Fu‐Da Yu, Liang Deng, Zhenjin Liang, Yunshan Jiang, Mei‐Yan Sun, Lei Zhao, Zhen‐Bo Wang
Abstract
Abstract Sodium-ion batteries stand a chance of enabling fast charging ability and long lifespan while operating at low temperature (low-T). However, sluggish kinetics and aggravated dendrites present two major challenges for anodes to achieve the goal at low-T. Herein, we propose an interlayer confined strategy for tailoring nitrogen terminals on Ti 3 C 2 MXene (Ti 3 C 2 -N funct ) to address these issues. The introduction of nitrogen terminals endows Ti 3 C 2 -N funct with large interlayer space and charge redistribution, improved conductivity and sufficient adsorption sites for Na + , which improves the possibility of Ti 3 C 2 for accommodating more Na atoms, further enhancing the Na + storage capability of Ti 3 C 2 . As revealed, Ti 3 C 2 -N funct not only possesses a lower Na-ion diffusion energy barrier and charge transfer activation energy, but also exhibits Na + -solvent co-intercalation behavior to circumvent a high de-solvation energy barrier at low-T. Besides, the solid electrolyte interface dominated by inorganic compounds is more beneficial for the Na + transfer at the electrode/electrolyte interface. Compared with of the unmodified sample, Ti 3 C 2 -N funct exhibits a twofold capacity (201 mAh g −1 ), fast-charging ability (18 min at 80% capacity retention), and great superiority in cycle life (80.9%@5000 cycles) at − 25 °C. When coupling with Na 3 V 2 (PO 4 ) 2 F 3 cathode, the Ti 3 C 2 -N funct //NVPF exhibits high energy density and cycle stability at − 25 °C."Image missing"