Flexible and Binder-Free Electrodes of Sb/rGO and Na3V2(PO4)3/rGO Nanocomposites for Sodium-Ion Batteries.

Flexible power sources have shown great promise in next-generation bendable, implantable, and wearable electronic systems. Here, flexible and binder-free electrodes of Na3V2(PO4)3/reduced graphene oxide (NVP/rGO) and Sb/rGO nanocomposites for sodium-ion batteries are reported. The Sb/rGO and NVP/rGO paper electrodes with high flexibility and tailorability can be easily fabricated. Sb and NVP nanoparticles are embedded homogenously in the interconnected framework of rGO nanosheets, which provides structurally stable hosts for Na-ion intercalation and deintercalation. The NVP/rGO paper-like cathode delivers a reversible capacity of 113 mAh g(-1) at 100 mA g(-1) and high capacity retention of ≈96.6% after 120 cycles. The Sb/rGO paper-like anode gives a highly reversible capacity of 612 mAh g(-1) at 100 mA g(-1) , an excellent rate capacity up to 30 C, and a good cycle performance. Moreover, the sodium-ion full cell of NVP/rGO//Sb/rGO has been fabricated, delivering a highly reversible capacity of ≈400 mAh g(-1) at a current density of 100 mA g(-1) after 100 charge/discharge cycles. This work may provide promising electrode candidates for developing next-generation energy-storage devices with high capacity and long cycle life.