Dopamine-derived N-doped carbon encapsulating hollow Sn4P3 microspheres as anode materials with superior sodium storage performance

Sn4P3 is one of the most promising anode materials for sodium ion batteries (SIBs) owning to the alloying reaction of P and Sn with Na to form Na3P and Na15Sn4, which is beneficial to achieve a high specific capacity, especially for the high volumetric capacity (6650 mAh cm−3). However, the high capacities generate large volume changes, which pulverize the anode material, resulting in poor cycling stability. This restricts its practical...