Phosphorus Nanoparticles Encapsulated in Graphene Scrolls as a High‐Performance Anode for Sodium‐Ion Batteries

Two composites of phosphorus nanoparticles encapsulated in graphene scrolls (P‐G) and phosphorus nanoparticles loaded on planar graphene sheets (P/G) were successfully prepared and applied as anodes for sodium‐ion batteries. Phosphorus nanoparticles (ca. 100–150 nm) were firstly obtained from commercial red phosphorus by using a simple flotation method. P‐G composites with different phosphorus contents (38.6, 52.2, and 62.1 %) were synthesized through a quick‐freezing process. In addition, the P/G composite with a phosphorus content of 50.8 % was prepared for comparison purposes. As a result, the P‐G composites showed a better performance than the P/G composite. Moreover, the P‐G composite with a phosphorus content of 52.2 % showed the best performance, delivering a capacity of 2355 mAh g −1 in the second cycle and 2172 mAh g −1 after 150 cycles at 250 mA g −1 (with a capacity retention of 92.3 %).