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. Flexible and binder-free Na₃V₂(PO₄)₃/reduced graphene oxide (rGO) cathodes and Sb/rGO anodes are fabricated. They exhibit high reversible capacity, excellent cyclability, and high rate capability. This work provides a new way to bendable, low-cost electrodes for next-generation sodium-ion batteries.