▎ 摘　　要

In this paper, a hollow sulfur@graphene oxide core-shell composite is synthesized for high-performance lithium-sulfur batteries through a facile two-step solution method with the assistance of polyvinylpyrrolidone. Scanning electron microscope observation shows that the hollow sulfur sphere is coated by the homogeneous graphene oxide nanolayer, and thermogravimetric analysis demonstrates the composite holds sulfur loading as high as 92 wt%. The composite served as cathode in lithium-sulfur batteries shows its capacity as high as 745 mAh g(-1) at 0.2C after 20 cycles. It also has an excellent cycling stability even at a high current density of 1C (73% retention and 96% coulombic efficiency after 150 cycles), implying that the diffusion of the polysulfides into electrolyte can be greatly inhibited. It is believed that the structure design of graphene oxide coated hollow sulfur sphere can be developed for the practical application of high-performance lithium-sulfur batteries. (C) 2015 Elsevier B.V. All rights reserved.