title: Electrochemical (de)lithiation of 1D sulfur chains in Li-S batteries: a model system study.
abstract: In contrast to the extensive studies of the electrochemical behavior of conventional cyclic S8 molecules in Li-S batteries, there has been hardly any investigation of the electrochemistry of S chains. Here we use S chains encapsulated in single- and double-walled carbon nanotubes as a model system and report the electrochemical behavior of 1D S chains in Li-S batteries. An electrochemical test shows that S chains have high electrochemical activity during lithiation and extinctive electrochemistry compared with conventional S8. The confined steric effect provides Li(+) solid-phase diffusion access to insert/egress reactions with S chains. During lithiation, the long S chains spontaneously become short chains, which show higher discharge plateaus and better kinetics. The unique electrochemistry of S chains supplements the existing knowledge of the S cathode mechanism and provides avenues for rational design of S cathode materials in Li-S batteries.
authors: CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS) , Beijing 100190, P. R. China.
authors: Chun-Peng
authors: CP
authors: Yang
authors: Ya-Xia
authors: YX
authors: Yin
authors: Yu-Guo
authors: YG
authors: Guo
authors: Li-Jun
authors: LJ
authors: Wan