Cost-effective and renewable paper derived hard carbon microfibers as superior anode for sodium-ion batteries

Sodium-ion batteries (SIBs) have attracted intense scientific attention as the most promising next generation energy storage device. However, the large-scale practical application of SIBs has been limited by exploring a low-cost and high performance anode material. Herein, hard carbon microfibers are successfully synthesized from renewable paper via simply carbonization procedure and proposed as anode materials for SIBs. The optimized carbonization at 1400 degrees C endows hard carbon microfibers high reversible charge capacity of 319.6 mAh g(-1), good rate capability as well as excellent cycle life with capacity retention of 99.3% after 100 cycles. The sodium storage mechanism is further investigated by virtue of various technologies, indicating that sodium ions are stored in inter- and intra-layers. Remarkably, a full cell with the as-prepared anode and a Na3V2(PO4)(3) cathode shows a favorable capacity of 243.8 mAh g(-1) and stable cyclability of 218.9 mAh g(-1) after 100 cycles. This study provides an opportunity for a cost-effective and renewable anode material for SIBs. (C) 2020 Elsevier Ltd. All rights reserved.