Maximizing catalytically active surface gallium for electrocatalysis of lithium polysulfides in lithium-sulfur batteries by silica@gallium core-shell particles

A novel silica@gallium core-shell structure is designed to maximize catalytically active surface gallium for highly efficient electrocatalysis of lithium polysulfides in lithium-sulfur batteries. The fabricated SiO2@Ga/S cathode battery exhibits a high reversible capacity of 927.1 mAh g(-1) at 0.75C and excellent cycling stability with a capacity retention rate of 85.97% for 600 cycles. When the sulfur mass loading is up to 6.5 mg cm(-2), the battery displays a high discharge capacity of similar to 4.145 mAh cm(-2) with high Coulombic efficiency of 85.04% after 200 cycles. Finally, a mechanism that the highly conductive electron-given-surface of liquid metal Ga shell on the surface of SiO2 in the thick electrodes for reversible electrocatalysis of lithium polysulfides in lithium-sulfur batteries is proposed.

Automated summary

By designing a novel silica@gallium core-shell structure for the cathode of lithium-sulfur batteries, highly efficient electrocatalysis of lithium polysulfides was achieved, leading to a high reversible capacity and excellent cycling stability. The proposed mechanism involves a highly conductive electron-given surface provided by the liquid metal gallium shell on the silica surface in thick electrodes for reversible electrocatalysis of lithium polysulfides in lithium-sulfur batteries.