Hasa Ivana, Buchholz Daniel, Passerini Stefano, Hassoun Jusef
Department of Chemistry, Sapienza University of Rome , Piazzale Aldo Moro, 5, 00185 Rome, Italy.
ACS Appl Mater Interfaces. 2015 Mar 11;7(9):5206-12. doi: 10.1021/am5080437. Epub 2015 Feb 27.
Herein, we report a study on P-type layered sodium transition metal-based oxides with a general formula of NaxMO2 (M = Ni, Fe, Mn). We synthesize the materials via coprecipitation followed by annealing in air and rinsing with water, and we examine the electrodes as cathodes for sodium-ion batteries using a propylene carbonate-based electrolyte. We fully investigate the effect of the Ni-to-Fe ratio, annealing temperature, and sodium content on the electrochemical performances of the electrodes. The impact of these parameters on the structural and electrochemical properties of the materials is revealed by X-ray diffraction, scanning electron microscopy, and cyclic voltammetry, respectively. The suitability of this class of P-type materials for sodium battery application is finally demonstrated by cycling tests revealing an excellent electrochemical performance in terms of delivered capacity (i.e., about 200 mAh g(-1)) and charge-discharge efficiency (approaching 100%).
在此，我们报道了一项关于通式为NaxMO2（M = Ni、Fe、Mn）的P型层状钠过渡金属基氧化物的研究。我们通过共沉淀法合成材料，随后在空气中退火并用水冲洗，并且使用基于碳酸丙烯酯的电解质将这些电极作为钠离子电池的阴极进行研究。我们全面研究了Ni与Fe的比例、退火温度和钠含量对电极电化学性能的影响。这些参数对材料结构和电化学性质的影响分别通过X射线衍射、扫描电子显微镜和循环伏安法得以揭示。通过循环测试最终证明了这类P型材料适用于钠电池应用，该测试显示出在放电容量（即约200 mAh g(-1)）和充放电效率（接近100%）方面具有优异的电化学性能。
