Synthesis of phosphorus-doped soft carbon as anode materials for lithium and sodium ion batteries

Phosphorus-doped soft carbon was synthesized by a facile phosphoric acid-assisted route. It is found that the phosphorus-doped soft carbon used as lithium ion battery anode exhibits a high reversible capacity of 333.6 mA h g(-1) with the first cycle coulombic efficiency of 87.0% at the current density of 30 mA g(-1). When used as sodium ion battery anode, it also shows great storage performance, with a reversible capacity of 121.3 mA h g(-1) with an initial coulombic efficiency of 65.0% at the current density of 10 mA g(-1). Besides, good rate capability and stable cycling performance are also observed for both lithium and sodium ion batteries, indicating potential of their application in large-scale storage devices.