Intimately coupled MoP nanocrystalline@carbon nanosheets-assembled hierarchical mesoporous nanospheres for high-performance sodium-ion storage

The development of metal phosphides with high reversible capacity and long lifespan as anode material for sodium-ion batteries has attracted tremendous interest. In this work, a simple chelation, carbonization and in-suit phosphorization process is design to construct the composite material of MoP@C. Ultrasmall MoP nanocrystalline with 5-6 nm in diameter is intimately and uniformly embedded inside ultrathin amorphous carbon nanosheets with about 10 nm in thickness, and then further assembled to hierarchical mesoporous nanospheres with abundant mesopores and large surface area (90.1 m(2) g(-1)). The multiple structural advantages remarkably enhance electrochemical activity, electronic conductivity and structural stability of MoP, and bring about the impressive sodium-ion storage performance with reversible capacity as high as 770 mAh g(-1) at current density of 0.5 A g(-1), excellent cycling stability (discharge capacity of 464 mAh g(-1) after 400 cycles at 1 A g(-1)), and outstanding rate-capability (average discharge capacity of 264 mAh g(-1) at 5 A g(-1)), highlighting great structural superiority of intimately coupled MoP nanocrystalline@carbon nanosheets and their hierarchical mesoporous nanospheres. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

The composite material of MoP@C constructed through a chelation, carbonization and in-situ phosphorization process exhibits excellent performance in sodium-ion batteries, including high reversible capacity, outstanding cycling stability, and exceptional rate capability.