A cerium vanadate/S heterostructure for a long-life zinc-ion battery: efficient electron transfer by the anchored sulfur

Ce0.25V2O5(H2O)center dot H2O (CeVO) or Ce0.3V2O5(H2O)center dot H2O/S (CeVS) was synthesized based on a facile one-step hydrothermal reaction of Ce(SO4)(2) and V2O5 or VS2. Rietveld refinement of CeVO unveils the intercalation of Ce ions into layered V2O5 with a large (001) lattice spacing of 12.1 angstrom. CeVS is a CeVO/S heterostructure, which originates from the hydrothermal transformation of VS2 -> V2O5 + S-8 and the simultaneous intercalation of Ce ions. The pre-intercalation of Ce ions leads to a Zn2+ migration barrier of 1.32 eV in CeVO, and CeVO shows a capacity of 376 mA h g(-1) at 0.1 A g(-1). However, CeVS exhibits a higher capacity (438 mA h g(-1)) and an ultralong lifespan with a capacity retention of 100% over 10 500 cycles at 5 A g(-1). The conversion between S-0 and vanadium sulfide (yS(0) + 2e(-) <-> S-y(2-)) in CeVS during the discharge and charge process can not only provide extra capacity, but also maintain the crystallinity and stability of CeVO, in which S transfers electrons like an electron shuttle to avoid the structural collapse and fast capacity fading of CeVO.

Automated summary

Ce0.3V2O5(H2O)·H2O/S (CeVS) material synthesized through hydrothermal reaction exhibits higher capacity and longer lifespan, maintaining the crystallinity and stability of Ce0.25V2O5(H2O)·H2O (CeVO) during the conversion process.