Highly Stable Basswood Porous Carbon Anode Activated by Phosphoric Acid for a Sodium Ion Battery

Looking for low-cost and environmentally friendly electrode materials can make a sodium ion battery a promising energy storage device. In this study, a stable p-doped biomass carbon (PBC) anode material is prepared from a natural basswood by phosphoric acid activation and carbonization, which is used for a sodium ion storage. As an anode, the best PBC-11 has a capacity of 326.3 mAh g-1 at 0.1 A g-1 after 500 discharges. After the reaction kinetics test, low impedance, fast sodium diffusion coefficient, and capacitance-dominated characteristics make the PBC-11 electrode have an excellent rate performance and maintain a capacity of ∼90.6% after 3000 cycles at a high current of 2 A g-1. The appropriate proportion of phosphoric acid activation plays a decisive role in the defects and porosity of carbon materials. Stable electrochemical performance and low material and preparation cost can make a Na+ storage one of the future power storage.