Robust hetero-MoO/MoO@N-doped carbon nanobelts decorated with oxygen deficiencies as high-performance anodes for potassium/sodium storage.

Hetero-MoO/MoO@N-doped carbon nanobelt anodes (h-MoO/MoO@NC) with long lifespan and superior rate capability were proposed by a simple in situ reduction tactic, in which pristine MoO was transformed into heterogeneous MoO/MoO. The hetero-MoO/MoO architecture significantly improves the electronic conductivity and affords abundant oxygen deficiencies. Meanwhile, the synergistic effect of internal MoO/MoO heterostructure and outer N-doped carbon layer (NC) accomplishes a balance of sustainable potassium/sodium storage and ultra-durable structure stability. In potassium ion batteries, the anodes steadily maintain a reversible capacity of 283 mAh g after 6000 cycles at 0.5 A g and 153 mAh g after 1000 cycles under 2 A g, as well as an impressive rate capability of 131 mAh g at 3 A g. In sodium ion batteries, the anodes purchase a steady capacity of 152 mAh g even after 10,000 cycles at 2 A g, and 190 mAh g after 5000 cycles at 0.5 A g. Moreover, the h-MoO/MoO@NC composite possesses a prominent pseudocapacitive effect and good thermal adaptability (-10 to 50 °C) in both KIBs and SIBs. The results indicate that the h-MoO/MoO@NC composite would be an auspicious material for potassium/sodium storage and other ion batteries.