Fang Yongzheng, Lian Ruqian, Li Huipeng, Zhang Ying, Gong Zhe, Zhu Kai, Ye Ke, Yan Jun, Wang Guiling, Gao Yu, Wei Yingjin, Cao Dianxue
Key Laboratory of Superlight Materials and Surface Technology (Ministry of Education), College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China.
Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, China.
ACS Nano. 2020 Jul 28;14(7):8744-8753. doi: 10.1021/acsnano.0c03259. Epub 2020 Jul 10.
Sodium (Na) metal batteries have attracted increasing attention and gained rapid development. However, the processing, storing, and application of Na metal anodes are restricted by its inherent stickiness and poor mechanical properties. Herein, an MXene (TiCT)-coated carbon cloth (TiCT-CC) host is designed and synthesized, which shows a highly metallic conductive and sodiophilic surface. After a thermal infusion treatment, a Na-TiCT-CC composite with rigidity and bendability is obtained and employed as a metal anode for Na ion batteries. The Na-TiCT-CC electrodes present stable cycling performance and high stripping/plating capacity in both an ether-based (up to 5 mA·h·cm) and a carbonate-based (up to 8 mA·h·cm) electrolyte. The fundamental protection mechanism of MXene TiCT is investigated. TiCT efficiently induces Na's initial nucleation and laterally oriented deposition, which effectively avoids the generation of mossy/dendritic Na. The arrangement of Na atoms deposited on the MXene surface inherits the MXene atomic architecture, leading to a smooth "sheet-like" Na surface. Meanwhile, a flexible Na-based Na-TiCT-CC∥NaV(PO) device is assembled and exhibits capable electrochemical performance.
钠（Na）金属电池已引起越来越多的关注并得到快速发展。然而，钠金属负极的加工、存储和应用受到其固有粘性和较差机械性能的限制。在此，设计并合成了一种涂覆有MXene（TiCT）的碳布（TiCT-CC）主体，其具有高度金属导电性和亲钠表面。经过热注入处理后，获得了具有刚性和可弯曲性的Na-TiCT-CC复合材料，并将其用作钠离子电池的金属负极。Na-TiCT-CC电极在醚基电解质（高达5 mA·h·cm）和碳酸盐基电解质（高达8 mA·h·cm）中均表现出稳定的循环性能和高脱溶/镀溶容量。研究了MXene TiCT的基本保护机制。TiCT有效地诱导了Na的初始成核和横向取向沉积，从而有效避免了苔藓状/树枝状Na的产生。沉积在MXene表面的Na原子排列继承了MXene的原子结构，形成了光滑的“片状”Na表面。同时，组装了柔性钠基Na-TiCT-CC∥NaV(PO)器件，并展示出良好的电化学性能。
