Hierarchical TiO2 spheres as highly efficient polysulfide host for lithium-sulfur batteries
نویسندگان
چکیده
Hierarchical TiO2 micron spheres assembled by nano-plates were prepared through a facile hydrothermal route. Chemical tuning of the TiO2 through hydrogen reduction (H-TiO2) is shown to increase oxygen-vacancy density and thereby modifies the electronic properties. H-TiO2 spheres with a polar surface serve as the surface-bound intermediates for strong polysulfides binding. Under the restricting and recapturing effect, the sulfur cathode could deliver a high reversible capacity of 928.1 mA h g(-1) after 50 charge-discharge cycles at a current density of 200 mA g(-1). The H-TiO2 additive developed here is practical for restricting and recapturing the polysulfide from the electrolyte.
منابع مشابه
Improving the capacity of lithium-sulfur batteries by tailoring the polysulfide adsorption efficiency of hierarchical oxygen/nitrogen-functionalized carbon host materials.
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