General Synthetic Strategy for Pomegranate-like Transition-Metal Phosphides@N-Doped Carbon Nanostructures with High Lithium Storage Capacity

Pomegranate-like nanostructured materials promise extensive applications in various fields due to their unique properties derived from special architectures. However, the controlled synthesis of pomegranate-like nanostructured materials remains challenging due to their complicated construction. Here, we develop a versatile synthetic approach to fabricate pomegranate-like transition-metal phosphides encapsulated in nitrogen-doped carbon nanospheres (TMP@N–Cs) through a direct vapor-phase leaching reduction of polydopamine (PDA)-coated transition-metal phosphates (TMPO@PDA). The distinctive TMP@N–C nanostructure has superior features for their applications in energy storage. For example, pomegranate-like Co2P@N–C when explored as anodes for Li-ion battery, possess faster Li-ion transport kinetics and improved electrical conductivity, demonstrating superior rate capability (discharge capacity of 412 mAh g–1 at a high current density 5 A g–1) and long cycle life (very stable capacity of 632 mAh g–1 over 300 cycles).