PDF(Pubmed)
Abstract：
Layered oxides of sodium-ion batteries suffer from severe side reactions on the electrode/electrolyte interface, leading to fast capacity degradation. Although surface reconstruction strategies are widely used to solve the above issues, the utilization of the low-cost wet chemical method is extremely challenging for moisture-sensitive Na-based oxide materials. Here, the solvation tuning strategy is proposed to overcome the deterioration of NaNi1/3Mn1/3Fe1/3O2 in water-based solution and conduct the surface reconstruction. When capturing the water molecules by the solvation structure of cations, here is Li+, the structural collapse and degradation of layered oxides in water-based solvents are greatly mitigated. Furthermore, Li(H2O)3EA+ promotes the profitable Li+/Na+ exchange to build a robust surface, which hampers the decomposition of electrolytes and the structural evolution upon cycling. Accordingly, the lifespan of Li-reinforced materials is prolonged to three times that of the pristine one. This work represents a step forward in understanding the surface reconstruction operated in a water-based solution for high-performance sodium layered oxide cathodes.
摘要：
钠离子电池的层状氧化物在电极/电解质界面上遭受严重的副反应，导致容量快速下降。尽管曲面重建策略被广泛用于解决上述问题，低成本的湿化学法的利用对水分敏感的钠基氧化物材料具有极大的挑战性。这里,提出了溶剂化调整策略，以克服NaNi1/3Mn1/3Fe1/3O2在水性溶液中的劣化，并进行表面重建。当通过阳离子的溶剂化结构捕获水分子时，这里是Li+，层状氧化物在水基溶剂中的结构崩溃和降解被大大减轻。此外，Li（H2O）3EA+促进有利可图的Li+/Na+交换，以建立一个强大的表面，这阻碍了电解质的分解和循环时的结构演变。因此，锂增强材料的寿命延长到原始材料的三倍。这项工作代表了在理解在高性能钠层状氧化物阴极的水基溶液中进行的表面重建方面迈出的一步。
