摘要
通过喷雾干燥法合成了三维石墨烯修饰的NaTi_2(PO_4)_3材料(NTP@rGO),结构测试表明,NaTi_2(PO_4)_3纳米颗粒表面被石墨烯包覆,同时,颗粒间通过三维石墨烯导电网络连接。电化学测试表明,NTP@rGO具有非常高的可逆容量(130 mAh g~(-1)),高的倍率性能(在200 C的电流密度下有38 mAh g~(-1))和长的循环稳定性(10 C倍率下循环1000周,容量保持率为77%)。同时,我们构建了全NASICON型的钠离子全电池(NTP@rGO//Na_3V_2(PO_4)_3/C),全电池同样表现出较高的可逆容量、较长的循环稳定性和优异的倍率性能。
Three-dimensional(3D) graphene-decorated NaTi_2(PO_4)_3(NTP@rGO) microspheres are successfully synthesized through a facile spray-drying method.Structural and morphological characterizations reveal that few layers of graphene are uniformly coated on the surface of NaTi_2(PO_4)_3 nanoparticles,which are tightly interconnected by a3 D graphene network to form NaTi_2(PO_4)_3@graphene microspheres.Electrochemical experiments show that the NTP@rGO electrode can deliver large reversible capacity(130 mAh g~(-1) at 0.1 C),high rate capability(38 mAh g~(-1)at 200 C) and long cycling stability(77%capacity retention after 1000 cycles at 20 C).Based on the NTP@rGO anode,an all-NASION-type Na-ion battery using a Na_3V_2(PO_4)_3/C cathode is assembled and tested to show very similar high capacity,high-power capability and long-term cycling stability to a Na//NTP@rGO half cell.
引文
