Compositing pine pollen derived carbon matrix with Na 4 FeV(PO 4 ) 3 nanoparticle for cost-effective sodium-ion batteries cathode

Na super -ion conductor type material Na 3 V 2 (PO 4 ) 3 has been widely researched as the cathode of sodium -ion batteries (SIBs) in recent years, but the unsatisfying cost of Na 3 V 2 (PO 4 ) 3 impedes its wide application in SIBs. In this study, iron element is used to replace part of vanadium in Na 3 V 2 (PO 4 ) 3 to reduce its expense, and pine pollen is applied for the first time as a very effective carbon source to improve the performance of Na 4 FeV(PO 4 ) 3 . The fabricated composite material achieves a capacity of 105 mA h g -1 under 0.2 C and fascinating cycling stability over 94 % under 2 C for 500 cycles and 98 % under 10 C for 1000 cycles. The excellent cycle performance is caused by the involvement of pine pollen that acts as a carbon matrix to enhance the electron conductivity and block the agglomeration of active material effectively, thus the well -dispersed nano sized Na 4 FeV (PO 4 ) 3 shortens the diffusion path of sodium ion and gains a remarkable rate capability. Moreover, the distinguished reversibility during the charge and discharge procedures is ascribed also to the robust structure of Na 4 FeV(PO 4 ) 3 . This work provides an efficient route to realize the economic cathode material of SIBs with good performance.