Abstract
LiPSs shuttle effect and cycling decay are still considered the main bottlenecks towards the practical application of Li-S batteries as commercial batteries. In the paper, we designed hollow SrTiO_3 microspheres wrapped by reduced graphene oxide (SrTiO_3@rGO) as efficient sulfur host materials with the aim of suppressing LiPSs shuttle and improving cycling stability of Li-S batteries. The hollow SrTiO_3 microspheres wrapped by rGO, with appropriate binding energy to LiPSs, provide balancing surface adsorption and diffusion of LiPSs on nonconductive SrTiO_3 and then promote its conversion on the interface, thus inhibiting the shuttle effect and greatly minimizing the active material irreversible loss in charge/discharge process. Meanwhile, the conductive rGO tightly wrapped on the surface of SrTiO_3 offers an interconnected conductive network to support the fast electron/ion transfer. Profit from these merits, the SrTiO_3 @rGO as sulfur host manifested superior cycling stability with a meager capacity decay rate of 0.0398% per cycle after 500 cycles at 0.2 C and an ultralow decay rate of 0.024% per cycle after 600 cycles at 1 C The superior cycling stability suggested the hollow SrTiO_3 @rGO was a potential candidate for the cathode of high-performance Li-S battery.
NSTL
Elsevier