Encapsulating Red Phosphorus in Ultralarge Pore Volume Hierarchical Porous Carbon Nanospheres for Lithium/Sodium-Ion Half/Full Batteries.

Abstract

Red phosphorus (P) has been recognized as a promising material for lithium/sodium-ion batteries (LIBs/SIBs) because of their high theoretical capacity. However, tremendous volume variation and low conductivity limit its widespread applications. Hence, we design and synthesize uniformly distributed honeycomb-like hierarchical micro-mesoporous carbon nanospheres (HHPCNSs) with ultralarge pore volume (3.258 cm³ g^-1) on a large scale through a facile way. The large pore volume provides enough space for loading of P and the expansion of P, and the uniform distribution of the micro-mesopores enables the red P to load uniformly. The resulting HHPCNSs/P composite exhibits extremely high capacity (2463.8 and 2367.6 mA h g^-1 at 0.1 A g^-1 for LIBs and SIBs, respectively), splendid rate performance (842.2 and 831.1 mA h g^-1 at 10 A g^-1 for LIBs and SIBs, respectively) and superior cycling stability (1201.6 and 938.4 mA h g^-1 at 2 and 5 A g^-1 after 1000 cycles for LIBs and 1269.4 and 861.8 mA h g^-1 at 2 and 5 A g^-1 after 1000 cycles for SIBs, respectively). More importantly, when coupled with LiFePO₄ and Na₃V₂(PO₄)₃ cathode, lithium/sodium-ion full batteries display high capacity and superior rate and cycling performances, revealing the practicability of the HHPCNSs/P composite. The exceptional electrochemical performance is caused by the honeycomb-like carbon network with ultralarge pore volume, uniformly distributed hierarchical micro-mesoporous nanostructure, outstanding electronic conductivity, and excellent nanostructural stability, which is much better than currently reported P/C materials for both LIBs and SIBs.