Loading Fe3O4 nanoparticles on paper-derived carbon scaffold toward advanced lithium-sulfur batteries

Lithium-sulfur batteries (LSBs) are regarded as a competitive next-generation energy storage device. However, their practical performance is seriously restricted due to the undesired polysulfides shuttling. Herein, a multifunctional interlayer composed of paper-derived carbon (PC) scaffold, Fe3O4 nanoparticles, graphene, and graphite sheets is designed for applications in LSBs. The porous PC skeleton formed by the interweaving long-fibers not only facilitates fast transfer of Li ions and electrons but also provides a physical barrier for the polysulfide shuttling. The secondary Fe3O4 @graphene component can reduce the polarization, boost the attachment of polysulfides, and promote the charging-discharging kinetics. The outer graphitic sheets layers benefit the interfacial electrochemistry and the utilization of S-containing species. The efficient obstruction of polysulfides diffusion is further witnessed via in situ ultraviolet-visible characterization and first-principles simulations. When 73% sulfur/commercial acetylene black is used as the cathode, the cell exhibits excellent capacity retention with high capacities at 0.5 C for 10 0 0 cycles and even up to 10 C for 500 cycles, an ultrahigh rate capability up to 10 C (478 mAh g(-1)), and a high areal sulfur loading of 8.05 mg cm(-2). The strategy paves the way for developing multifunctional composites for LSBs with superior performance. (c) 2020 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.