Hierarchical Microcables Constructed by CoP@C subset of Carbon Framework Intertwined with Carbon Nanotubes for Efficient Lithium Storage

Transition-metal phosphides (TMPs)-based electrode materials with high capacity have attracted considerable interest as a promising anode material for lithium-ion batteries (LIBs). Herein, a hierarchical cable-like structure composed of CoP@C core-shell nanoparticles (NPs) encapsulated in one-dimensional (1D) porous carbon framework intertwined with N-doped carbon nanotubes (CoP@C subset of PCF/NCNTs) is synthesized by a self-templating, self-catalytic, and subsequent vapor-phase phosphorization strategy. The unique nanoarchitecture regime provides multiple advantages. The 1D carbon framework allows for quick ion and electron access, maintaining the integrity and accommodating the volume change of the structure during repeated discharging/charging. The internal carbon shell can prevent the direct aggregation of CoP NPs on cycling. The external NCNTs on the surface supply a staggered conductive network to promote electrolyte penetration and charge transportation. Impressively, the as-fabricated hybrid nanocables deliver a reversible capacity of 712 mAh g(-1) at 0.5 A g(-1) for over 700 cycles with excellent rate capability as an anode material for LIBs. The significantly improved lithium storage properties of CoP@C subset of PCF/NCNTs reveal the importance of reasonable design and engineering of novel hierarchical structures with higher complexity.