Carbon coated Co(PO3)2/CoSe2 heterostructure as high performance sodium storage anode

Abstract

Heterostructure fabrication is believed to acquire promoted charge transfer and improved surface storage contribution, thus obtaining high-performance anodes for sodium-ion batteries. Herein, the simultaneous phosphatization and selenization of polydopamine functionalized ZIF-67 is adopted to engineer N-doped carbon coated Co(PO3)2/CoSe2 heterostructure. The hetero-interface with plenty of surface sites is activated with large surface reaction and fast sodium ion transport dynamics. The multiphase synergism and carbon coating layer assure high conductivity and structural stability. The designed sample delivers impressive anode performance, exhibiting a high sodium storage capacity of 333.4 mAh g−1 at 0.1 A g−1 and 192.7 mAh g−1 after 1000 cycles at 2 A g−1. This simple and reasonable method can be utilized to construct other transition metal based heterostructures with multiphase synergism for the application of advanced anodes.