title: In Situ Reactive Synthesis of Polypyrrole-MnO2Coaxial Nanotubes as Sulfur Hosts for High-Performance Lithium-Sulfur Battery.
abstract: Lithium-sulfur batteries are considered as a promising candidate for high energy density storage applications. However, their specific capacity and cyclic stability are hindered by poor conductivity of sulfur and the dissolution of redox intermediates. Here, we design polypyrrole-MnO2coaxial nanotubes to encapsulate sulfur, in which MnO2restrains the shuttle effect of polysulfides greatly through chemisorption and polypyrrole serves as conductive frameworks. The polypyrrole-MnO2nanotubes are synthesized through in situ polymerization of pyrrole using MnO2nanowires as both template and oxidization initiator. A stable Coulombic efficiency of ∼98.6% and a decay rate of 0.07% per cycle along with 500 cycles at 1C-rate are achieved for S/PPy-MnO2ternary electrodes with 70 wt % of S and 5 wt % of MnO2. The excellent trapping ability of MnO2to polysulfides and tubular structure of polypyrrole with good flexibility and conductivity are responsible for the significantly improved cyclic stability and rate capability.
authors.affiliation: Materials Science and Engineering Program and Department of Mechanical Engineering, The University of Texas at Austin , Austin, Texas 78712, United States.|College of Materials Science and Engineering, Zhejiang University of Technology , 18 Chaowang Rd, Hangzhou 310014, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Materials Science and Engineering Program and Department of Mechanical Engineering, The University of Texas at Austin , Austin, Texas 78712, United States.
authors.forename: Ye
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Materials Science and Engineering Program and Department of Mechanical Engineering, The University of Texas at Austin , Austin, Texas 78712, United States.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ding
authors.affiliation: College of Materials Science and Engineering, Zhejiang University of Technology , 18 Chaowang Rd, Hangzhou 310014, China.
authors.forename: Wenkui
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Materials Science and Engineering Program and Department of Mechanical Engineering, The University of Texas at Austin , Austin, Texas 78712, United States.
authors.forename: Guihua
authors.initials: G
authors.lastname: Yu
keywords: in situ polymerization; lithium−sulfur batteries; manganese dioxide; nanotubes; polypyrrole