聚合物辅助生成焦磷酸铌NbP1.8O7用于钠离子电池负极

Amorphous niobium pyrophosphate(NbP 1.8 O 7)as high rate anode of Na-ion batteries

提出一种利用聚合物合成焦磷酸铌NbP1.8O7的简易方法,采用聚合物辅助一步煅烧,通过调控含磷聚合物的加入量来制备纯相的焦磷酸铌,调控煅烧升温速率以进一步提高负极材料的无定型化,考察电极材料的电化学性能。结果表明:优化后的电极材料电化学储钠性能优异;制备5℃/min升温速率下的趋于无定形的焦磷酸铌在1 000 mA/g的电流密度下循环5 000圈后可逆放电比容量仍有164.6 mA·h/g,在2 000 mA/g的大电流密度下循环5 000圈后仍有101.37 mA·h/g的高可逆比容量。

A simple method for the synthesis of niobium pyrophosphate NbP 1.8 O 7 using polymer was proposed.A polymer-assisted one-step calcination was used to prepare pure-phase niobium pyrophosphate by regulating the addition amount of phosphorus-containing polymer.The calcination heating rate was adjusted to further improve the amorphization of the anode material.Then the electrochemical performance of the electrode material was investigated.The results show that the optimized electrode materials present excellent electrochemical sodium storage performance.Niobium pyrophosphate tends to be more amorphous at temperature rise rate of 5℃/min and exhibits better electrochemical performance.It has a reversible discharge capacity of 164.6 and 101.37 mA•h/g after 5000 cycles at a current density of 1000 mA/g and 2000 mA/g.