Rationally Designed Three-Layered TiO2 @amorphous MoS3 @Carbon Hierarchical Microspheres for Efficient Potassium Storage

Abstract

Amorphous MoS₃ has been an attractive electrode material for sodium-ion batteries and lithium-sulfur batteries. However, the potassium storage capability of amorphous MoS₃ remains unreported. Herein, the construction of hybrid hierarchical microspheres composed of amorphous MoS₃ nanosheets dual-confined with TiO₂ core, and nitrogen-doped carbon shell layer (denoted as TiO₂ @A-MoS₃ @NC) via a self-templating method, combined with a low-temperature sulfurization process as a new anode material for potassium-ion batteries (PIBs), is reported. Benefitting from the unique structural merits including unique 1D chain structure, disordered arrangement of atoms and a large number of defects of amorphous MoS₃ , more active heterointerfacial sites, effectively mitigated volume change, good electrical contact, and easy K⁺ ion migration, the TiO₂ @A-MoS₃ @NC microspheres exhibit excellent potassium-storage performance with high specific capacity, superior rate capability, and cycling stability.

Keywords: amorphous MoS 3; microspheres; nanosheets; potassium−ion batteries.