High loading FeS2 nanoparticles anchored on biomass-derived carbon tube as low cost and long cycle anode for sodium-ion batteries

In recent years, the sodium storage mechanism and performance optimization of FeS2 have been studied intensively. However, before the commercial application of FeS2, preconditions of low-cost, simple craft and scale production of nanoscale FeS2 are also essential. Based on above challenges, mesh-like FeS2/carbon tube/FeS2 composites are prepared simply from green, low-cost and renewable natural herb in this work. With the assistance of protogenetic interconnected carbon tube network (only 5.3 wt%), FeS2/carbon tube/FeS2 composites show high capacity (542.2 mA h g−1), good stability (< 0.005% per cycle over 1000 cycles), and excellent rate performance (426.2 mA h g−1 at 2 A g−1). The outstanding electrochemical performance of FeS2/carbon tube/FeS2 composites may be attributed to the unique interconnected reticular structure, meaning that FeS2 nanoparticles are effectively immobilized by carbon tube network via physical encapsulation and chemical bonding. More importantly, this work may provide green and low cost preparation method for specially structured metal sulfides/carbon composites, which promotes their commercial utilization in environmentally friendly energy storage system.