Solvent-free template synthesis of SnO2/C hybrid hollow spheres for superior lithium-sulfur batteries

Abstract

Hollow structures could be promising for various applications such as lithium-sulfur batteries (LSBs). The existing two types of synthesis routes to fabricate hollow structures include vapor processing route and solution processing route. Herein, we report a new and facile solvent-free template (SFT) synthetic strategy for the synthesis of SnO2/C hybrid hollow spheres by mixing and heating solid raw materials, in which 3-aminophenol/formaldehyde (APF) resin spheres and Tin salt have been used as hard template and precursor, respectively. During heating, Tin salt is melted and the ions can diffuse into the insides of APF spheres easily, leading to effective loading ions, thus to successfully shape replication of template. Sulfur cathode containing the as-prepared porous SnO2/C hybrid hollow spheres exhibited superior electrochemical performances for lithium-sulfur batteries. The present SFT strategy will pave a new avenue for the synthesis of mixed carbon/metal oxides hollow spheres and their promising application in different areas.