The Importance of Confined Sulfur Nanodomains and Adjoining Electron Conductive Pathways in Subreaction Regimes of Li‐S Batteries. Issue 19 (8th June 2017)

• Record Type: Journal Article
• Authors: Park, Jungjin; Kim, Eui Tae; Kim, Chunjoong; Pyun, Jeffrey; Jang, Hyung‐Seok; Shin, Jaeho; Choi, Jang Wook; Char, Kookheon; Sung, Yung‐Eun
• Is Part Of: Advanced energy materials. Volume 7:Issue 19(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-06-08
• Subjects: capping agents -- electrochemical analyses -- lithium‐sulfur batteries -- polysulfide kinetics -- sulfur‐carbon copolymers; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.201700074
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: Polysulfide dissolution into the electrolyte and poor electric conductivity of elemental sulfur are well‐known origins for capacity fading in lithium–sulfur batteries. Various smart electrode designs have lately been introduced to avoid these fading mechanisms, most of which demonstrate significantly improved cycle life. Nevertheless, an in‐depth understanding on the effect of sulfur microstructure and nanoscale electron transport near sulfur is currently lacking. In this study, the authors report an organized nanocomposite comprising linear sulfur chains and oleylamine‐functionalized reduced graphene oxide ( O ‐rGO) to achieve robust cycling performance (81.7% retention after 500 cycles) as well as to investigate the reaction mechanism in different regimes, i.e., S8 dissolution, polysulfide conversion, and Li2 S formation. In the nanocomposite, linear sulfur chains terminate with 1, 3‐diisopropylbenzene are covalently linked to O ‐rGO. The comparison with control samples that do not contain either the capping of sulfur chains or O ‐rGO reveals the synergistic interplay between both treatments, simultaneously unveiling the distinct roles of confined sulfur nanodomains and their adjoining electron pathways in different reaction regimes. Abstract : Organized nanocomposite comprising linear sulfur chains and oleylamine‐functionalized reduced graphene oxide is used as a conducting co‐polymeric active material in Li‐S batteries to achieve exceptional cycle retention and improved rate capability. The systematic analyses coherently reveal that confined sulfur nanodomains and adjoining electric conductive pathways are both critical for facile reactions in all three regimes, offering a useful design rule for sulfur electrodes.