Generalitat de Catalunya, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), European Commission, Ministerio de Ciencia e Innovación (España), Consejo Superior de Investigaciones Científicas (España), Jacas Biendicho, Jordi [0000-0001-5981-6168], Mazaira, Pedro [0009-0002-6314-4725], Zhang, Chaoqi [0000-0002-0357-235X], Missyul, Alexander [0000-0002-0577-4481], Arbiol, Jordi [0000-0002-0695-1726], Jacas Biendicho, Jordi, Mazaira, Pedro, Avireddy, Hemesh, Zhang, Chaoqi, Tang, Peng-Yi, Missyul, Alexander, Trilla, Lluis, Arbiol, Jordi, Morante, Joan Ramón, Cabot, Andreu, Generalitat de Catalunya, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), European Commission, Ministerio de Ciencia e Innovación (España), Consejo Superior de Investigaciones Científicas (España), Jacas Biendicho, Jordi [0000-0001-5981-6168], Mazaira, Pedro [0009-0002-6314-4725], Zhang, Chaoqi [0000-0002-0357-235X], Missyul, Alexander [0000-0002-0577-4481], Arbiol, Jordi [0000-0002-0695-1726], Jacas Biendicho, Jordi, Mazaira, Pedro, Avireddy, Hemesh, Zhang, Chaoqi, Tang, Peng-Yi, Missyul, Alexander, Trilla, Lluis, Arbiol, Jordi, Morante, Joan Ramón, and Cabot, Andreu
A new cathode material, FeS2-decorated carbon nanofiber (CNF), is proposed for Li-S batteries. The structure and physicochemical properties of the material have been engineered to enhance the poor cycling stability typically displayed by sulfur composites. The composite material shows a complex architecture with a matrix of CNF hosting the sulfur and core-shell FeS2 nanoparticles acting as a catalyst for a solid phase conversion-type reaction. This cathode delivers high discharge capacities of 864, 798, 689, 595 and 455 mAhg−1 at C/10, C/5, C/2, 1C and 2C, respectively, with a stable capacity retention of 87% at 2C after 300 cycles. FeS2-decorated CNF has been characterised using several techniques, including in-situ battery measurements at the ALBA synchrotron facility and high-throughput microscopy, giving valuable insights into its charge/discharge reaction mechanism. The excellent performance obtained is combined with the use of just low-cost and abundant elements such as iron, sulfur and carbon, which makes this battery highly promising for the next generation of electrochemical energy storage devices.