Optimized Cerium vanadate catalytic host with simple heterostructure engineering achieving regulated polysulfide...

Meliorating the behavior deposition of lithium polysulfides (LiPS) is crucial for enhancing the electrochemical performance of sulfur cathodes, which could be implemented by the precise modulation on the catalytic host. Herein, heterostructure engineering is employed to tune up the catalytic capability of CeVO₄, by introducing CeO₂ through a simple adjustment in the addition sequence of reactants. The formed CeVO₄/CeO₂ heterostructure has been demonstrated to exhibit appropriate interaction strength with LiPS for accelerating the catalytic conversion process, as well as an engineered surface for inducing three dimensional (3D) Li₂S deposition, thereby endowing the corresponding sulfur cathodes with excellent electrochemical performance under harsh conditions. The S/CeVO₄/CeO₂ cathode could deliver a high capacity of 36.5 mAh cm^-2 (1278.9 mAh g^-1) under high sulfur loading of 28.5 mg cm^-2 and lean electrolyte dosage of 6 μL mg^-1, and also function well even under a wide temperature range (-30 ∼ 60 °C) or matching with polymer solid electrolyte. This work offers a simple yet practical strategy to modulate the catalysts for sulfur cathodes with heterostructure design, thereby advancing the practical implementation of the lithium-sulfur battery.