Heteroatomic interface engineering of MOF-derived metal-embedded P- and N-codoped Zn node porous polyhedral carbon with enhanced sodium-ion storage

Amorphous-ordered mesoporous carbon materials are regarded as the most promising anode candidate for sodium-ion batteries (SIBs) owing to their eco-friendliness, abundance, thermal stability, and low price. However, poor rate, low initial Coulombic efficiency, and poor cycling performance have been the major challenges of SIBs. Herein, we successfully constructed a robust phosphorus and nitrogen-codoped Zn node porous polyhedral carbon polyhedron (P-N-Zn-C). The as-prepared P-N-Zn-C anode delivers outstanding electrochemical performance and ultrahigh stability and has achieved a remarkable capacity of 460 mA h g-1 at 100 mA g-1, long-term cycling stability of up to 100 cycles, and an excellent rate performance even at a current density of up to 1000 mA g-1. The remarkable performance can be ascribed to the enlarged interlayer distances of carbon and the existence of Zn node, which facilitate the insertion-extraction of Na ions. The first-principles density functional theory calculations revealed that the presence of P, N, and Zn could reduce the band gaps between the valence and conduction bands and accelerate the electron transfer reaction rate. This study underscores the potential importance of heteroatom doping as an effective strategy for improving the performance of carbon electrode materials.