ENERGY MATERIALS Centrifugally spun porous carbon microfibers as interlayer for Li–S batteries Meltem Yanilmaz 1,2 , Abdullah M. Asiri 3,4, *, and Xiangwu Zhang 1,3, * 1 Fiber and Polymer Science Program, Department of Textile Engineering, Chemistry and Science, Wilson College of Textiles, North Carolina State University, Raleigh, NC 27695-8301, USA 2 Department of Textile Engineering, Istanbul Technical University, Istanbul, Turkey 3 Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia 4 Department of Chemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia Received: 24 July 2019 Accepted: 12 November 2019 Ó Springer Science+Business Media, LLC, part of Springer Nature 2019 ABSTRACT Lithium–sulfur (Li–S) batteries have attracted great interest owing to their high energy density. However, shuttling of polysulfides deteriorates the electro- chemical performance of Li–S batteries and prevents their practical applications. Placing a conductive and porous interlayer structure between the cathode and the separator limits the shuttling effect and improves the cycling performance. Here, porous carbon microfibers are fabricated via a fast, safe and cost-effective centrifugal spinning approach and the resultant centrifugally spun porous carbon microfibers (CS-PCMFs) are evaluated for use as an interlayer in Li–S batteries. The highly porous fibrous structure is observed from SEM and TEM images, and a high initial discharge capacity of 1485 mAh g -1 is achieved. A high reversible capacity of 615 mAh g -1 is reached after 200 cycles at 0.2 C. In addition, the cell with CS-PCMF interlayer has low cell resistance of 25 O, whereas that of Li–S cell without interlayer is 55 O. Owing to the low cell resistance, the cell with CS-PCMF interlayer delivers the reversible capacity of around 600 mAh g -1 at 1 C, while the cell without interlayer exhibits a lower capacity of 250 mAh g -1 . Therefore, this work provides a new approach for designing highly porous carbon microfiber interlayer for Li–S batteries with exceptional electrochemical performance. Introduction Rechargeable lithium-ion batteries have been com- monly used in portable electronic devices, electric vehicles, etc., and the demand for higher energy density and longer life cycle has been increasing. Lithium–sulfur (Li–S) batteries have been considered as the promising energy storage system for large- scale energy storage applications and electric vehicles due to the high theoretical energy density (2600 Wh kg -1 ) and the merits of sulfur including high theoretical specific capacity (1675 mAh g -1 ), Address correspondence to E-mail: aasiri2@kau.edu.sa; xiangwu_zhang@ncsu.edu https://doi.org/10.1007/s10853-019-04215-y J Mater Sci Energy materials