Synthesis of Double-Shell SnO₂@C Hollow Nanospheres as Sulfur/Sulfide Cages for Lithium–Sulfur Batteries

Abstract

Double-shell SnO@C hollow nanospheres were synthesized by a template method, and then the sulfur was loaded to form a cathode material of S/SnO@C composite. In Li-S batteries, it delivered a high initial specific capacity of 1473.1 mAh/g at a current density of 200 mA/g, and the capacity retention was even up to 95.7% over 100 cycles at 3200 mA/g, i.e., a capacity fade rate of only 0.043% per cycle. These good electrochemical performances should be attributed to the SnO@C hollow nanospheres. They can enhance the electronic conductivity by the outside carbon shell, and confine the lithium polysulfides by S-Sn-O and S-C chemical bonds to suppress the shuttle effect. Besides, the hollow nanospheres can readily accommodate the sulfur/sulfides to prevent the electrical/mechanical failure of the cathode, instead of their agglomeration on the external surface of SnO@C.

Sulfiphilic Few‐Layered MoSe2 Nanoflakes Decorated rGO as a Highly Efficient Sulfur Host for Lithium‐Sulfur Batteries

“…Correspondingly, struggling pursuit of a more competitive candidate becomes an urgent task. For instance, many kinds of carbon matrix have been deployed to hold up the sulfur, like hollow carbon spheres (HCSs) [10,11] and hollow nanofibers or nanotubes, [12][13][14] graphene oxide sheets, [15,16] and 3D hierarchical porous carbon. [5] Furthermore, sulfur is abundant on earth, nontoxic, and environmentally friendly.…”

Fabrication Methods of Porous Carbon Materials and Separator Membranes for Lithium–Sulfur Batteries: Development and Future Perspectives

“…c) Cycling performance of sulfur‐embedded hollow‐sphere materials. Reproduced with permission . Copyright 2016, The American Chemical Society.…”

Recent development of metal compound applications in lithium–sulphur batteries

“…To further enhance the conductivity and thus enhance the performance, double-shell SnO 2 @C hollow nanospheres were designed to encapsulate sulfur by Cao. 98 The S/SnO 2 @C composite illustrated a high reversible capacity of 616 mA h/g at 3200 mA/g after 100 cycles.…”

“…Finally, the nanostructures of metal compounds, i.e., surface area, pore size, pore volume, as well as particle size are also important factors which influence the performance of Li-S batteries. 19 Generally the metal compounds with smaller size, 69 high surface area and pore volume, 98 and abundant micro/mesopores 49,57 are beneficial to the cathode. Even though tremendous progress in improving the electrochemical performance and understanding the reaction mechanisms of Li-S batteries have been achieved, Li-S batteries are far from being ready for practical use at this stage.…”