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论文类型：期刊论文

发表时间：2020-01-10

发表刊物：ELECTROCHIMICA ACTA

收录刊物：EI、SCIE

卷号：330

ISSN号：0013-4686

关键字：Lithium sulfur batteries

摘要：Metal sulfides (MS) have been widely explored in lithium-sulfur batteries (LSB) owing to their stronger affinity with lithium polysulfide species (LPS) than carbon materials and higher electronic conductivity compared with metal oxides. However, practical application of MS based sulfur cathodes is hindered by a slow conversion of sulfur species due to limited catalytic effect of MS for redox reactions of sulfur, and by the absence of a continuous conducting network in the cathode. To address these issues, we herein report the design and fabrication of a heterostuctured Co3S4/MnS nanotube array grown on carbon cloth (CC@CMS-NA) as a catalytic sulfur host for high performance LSB. According to the theoretical calculations and electrochemical test, Mn dopants can tune the electronic structure of Co3S4 to adsorb soluble LPS more effectively and engineer a catalytic heterogeneous surface to facilitate charge transport and enhance the conversion kinetics of sulfur species. Meanwhile, the 3D array structure avoids "dead" sites caused by the use of binder and conductive additive, and also provides rapid electron transport path. As a result, the CC@CMS-NA based sulfur cathodes with 3.2 mg cm(-2) sulfur loading exhibits an excellent cycle performance at a current density of 2.67 mA cm(-2) (95% retention of initial specific capacity after 200 cycles, namely 0.02% decay per cycle). Our work demonstrates that reasonable construction of heterogeneous structures is a promising strategy to improve the performance of MS based LSB. (C) 2019 Elsevier Ltd. All rights reserved.